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Experience-dependent genetic and synaptic regulation of stability and plasticity in cortical circuits

Date:
28
Thursday
September
2023
Lecture / Seminar
Time: 11:00-12:15
Location: The David Lopatie Hall of Graduate Studies
Lecturer: Dahlia Kushinsky-Student Seminar PhD Thesis Defense
Organizer: Department of Brain Sciences
Contact: naomi.moses@weizmann.ac.il
Details:
Abstract: Neural circuits in the brain must be plastic enough to allow an animal to adapt ... Read more Neural circuits in the brain must be plastic enough to allow an animal to adapt to and learn from new experiences yet they must also remain functionally stable such that previously learned skills and information are retained. Thus, fundamental questions in neuroscience concern the molecular, cellular, and circuit mechanisms that balance the plasticity and stability of neural circuits. During my studies, I investigated these mechanisms in three studies that focused on sensory- and behavioral state-dependent changes in transcription and GABAergic inhibition in the visual cortex of adult mice. In my Ph.D. defense, I will elaborate on the novel molecular-cellular mechanisms that I discovered in these studies and discuss their role in conveying both plasticity and stability to visual processing and perception.
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The Southern Lights — Rhodopsin Complexes Discovered in an Algae Near Antarctica Can Help Unravel the Secrets of the Brain

Date:
16
Monday
October
2023
Colloquium
Time: 11:00-12:15
Location: Gerhard M.J. Schmidt Lecture Hall
Lecturer: Dr. Moran Shalev-Benami
Organizer: Department of Chemical and Structural Biology
Contact: sarah.amzallag@weizmann.ac.il
Abstract: Rhodopsins are a ubiquitous family of light sensing/signaling proteins. In recen ... Read more Rhodopsins are a ubiquitous family of light sensing/signaling proteins. In recent work, our group discovered an intriguing family of rhodopsins in algae: the bestrhodopsins. Through cryo-EM and comprehensive biochemical and electrophysiological studies, we showed that bestrhodopsins are fusions of rhodopsins and ion channels which assemble as mega-complexes to enable light-controlled passage of ions across membranes. Regulation of a classical ion channel by an attached photoreceptor has never been found before in nature, and previous attempts to engineer light-regulated fused channels have yielded limited success. The discovery and characterization of bestrhodopsins thus provide a new template for designing proteins with light-sensing and ion-conducting activities, as well as represent a platform for regulating cellular signaling in living organisms using light. These findings are therefore not only important as a basic scientific discovery but also for the field of optogenetics where neural activity is controlled by light. In the present talk, I will present the discovery of the bestrhodopsins, and explain how we use our cryo-EM work for structure-based design of dramatically improved tools to manipulate signaling cascades in cells by light control, paving the way for the next generation of optogenetics tools to study brain function in vivo.
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The Southern Lights — Rhodopsin Complexes Discovered in an Algae Near Antarctica Can Help Unravel the Secrets of the Brain Colloquium website

Immunology and Regenerative Biology Colloquium

Date:
18
Wednesday
October
2023
Lecture / Seminar
Time: 11:00
Title: Multi-Potent Lung Stem Cells for Lung Regeneration
Location: Max and Lillian Candiotty Building
Lecturer: Prof. Yair Reisner
Organizer: Department of Immunology and Regenerative Biology
Contact: ronen.alon@weizmann.ac.il

Disordered crystals as viewed by light scattering

Date:
23
Monday
October
2023
Colloquium
Time: 11:00-12:15
Location: Gerhard M.J. Schmidt Lecture Hall
Lecturer: Dr. Omer Yaffe
Organizer: Department of Chemical and Biological Physics
Contact: sarah.amzallag@weizmann.ac.il
Abstract: In materials science, there is a prevailing paradigm that single crystals are al ... Read more In materials science, there is a prevailing paradigm that single crystals are almost perfectly ordered, allowing their structure to be precisely represented as a unit cell, from which their electronic and mechanical properties can be derived. However, our research has uncovered that thermal motion disrupts this ideal representation in numerous materials, including halide perovskites, ion conductors, and organic semiconductors. In this talk, I will describe our journey to comprehend thermal motion in single crystals through Raman spectra. We investigate the discrepancies between experimental observations of light scattering and theoretical predictions and consider the coupling between vibrational modes. Furthermore, we explore how such coupling impacts the functional properties of these crystals.
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Disordered crystals as viewed by light scattering Colloquium website

Immunology and Regenerative Biology Colloquium

Date:
17
Wednesday
January
2024
Lecture / Seminar
Time: 11:00-12:00
Title: "Heterogeneity and functional specialization of blood vessels in bone"
Location: Max and Lillian Candiotty Building
Lecturer: Prof. Ralf H. Adams
Organizer: Department of Immunology and Regenerative Biology
Contact: tsvee.lapidot@weizmann.ac.il

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    Effects of cocaine use on organization and dimensionality of neural representations in rat orbitofrontal cortex

    Date:
    18
    Monday
    September
    2023
    Lecture / Seminar
    Time: 14:00-15:00
    Location: Nella and Leon Benoziyo Building for Brain Research
    Lecturer: Prof. Geoffrey Schoenbaum MD/PhD
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Room 113 Host:rony.paz@weizmann.ac.il For accessibility issues: naomi.mose ... Read more Room 113 Host:rony.paz@weizmann.ac.il For accessibility issues: naomi.moses@weizmann.ac.il
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    Abstract: Substance use disorder can be partly understood as a failure to properly learn a ... Read more Substance use disorder can be partly understood as a failure to properly learn about or use information about consequences, particularly when they are rare, delayed, or even anecdotal. Such behaviors require access to cognitive models to allow estimation of likely outcomes, capabilities which depend critically on prefrontal and particularly orbitofrontal areas in rats, monkeys, and humans. We have previously shown that prior cocaine use disrupts performance in a variety of experimental settings that isolate orbitofrontal-dependent, inference-based behavior. In the current experiment, I will describe the effect of prior cocaine use on the organization of information by neural ensembles in rat orbitofrontal and prelimbic cortices during performance of a multi-dimensional choice task.
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    Ph.D. Defense Seminar

    Date:
    04
    Monday
    September
    2023
    Lecture / Seminar
    Time: 11:30-12:30
    Title: The reasons behind better DNA preservation in the petrous bone: cellular and 3D structural analysis of modern pig and ancient human petrous bones
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Jamal Ibrahim
    Organizer: Scientific Archeology Unit
    Contact: jamal.ibrahim@weizmann.ac.il
    Details: The seminar will be also via zoom: Meeting ID: 940 5265 6196 Meeting password: 449244

    Understanding spontaneous neuronal activity with neurophotonics

    Date:
    30
    Wednesday
    August
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Anna Devor
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il For accessibility issues: ... Read more Host: Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il For accessibility issues: naomi.moses@weizmann.ac.il
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    Abstract: The last decade has seen a rapid advance of neurophotonic technologies, in large ... Read more The last decade has seen a rapid advance of neurophotonic technologies, in large part thanks to the BRAIN Initiative as well as other large-scale neuroscience projects in the US and around the world. We now have a large array of diverse experimental and computational tools to study the brain across species, scales, levels of description, in animals and humans. Notably, the lion’s share of these technologies falls under the general umbrella of neurophotonics. This lecture will focus on several microscopic neurophotonic technologies in the context of understanding spontaneous neuronal and neurovascular activity in the mouse cerebral cortex. Among these tools is optically transparent Windansee electrode arrays that can be combined with optical imaging. Combining Windansee recordings with two-photon imaging and biophysical modeling, we show that spontaneous inputs to layer 1 were coded by a selective, sparse sub-population of local neurons. This is in contrast with earlier studies in the same system where each instance of a sensory input activated a different subset of neurons indicating redundancy in coding. Because selective coding by a few “oracle” neurons is nonredundant, we are tempted to speculate that the health of internally generated brain activity may be more vulnerable to damage or disease compared to that in response to external stimuli. Light refreshments before the seminar
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    The safety pharmacology of Syk inhibitors: Cardiovascular complications resulting from off-target tyrosine kinase inhibition

    Date:
    24
    Monday
    July
    2023
    Lecture / Seminar
    Time: 14:00-15:00
    Location: Max and Lillian Candiotty Building
    Lecturer: Ms. Marieke Van Daele
    Organizer: Dwek Institute for Cancer Therapy Research
    Contact: michalav@weizmann.ac.il

    Plant structure and motion as inspiration for bioinspired buildings and soft machines

    Date:
    18
    Tuesday
    July
    2023
    Lecture / Seminar
    Time: 11:30-12:30
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Prof. Thomas Speck
    Organizer: Department of Plant and Environmental Sciences
    Contact: david.zeevi@weizmann.ac.il
    Details: Host: Dr. David Zeevi

    Tools & Techniques Seminar

    Date:
    18
    Tuesday
    July
    2023
    Lecture / Seminar
    Time: 10:00-11:00
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Saar Ezagouri/Moshe Goldsmith/Elad Stolovicki
    Organizer: Department of Biomolecular Sciences
    Contact: levana.ayvazo@weizmann.ac.il
    Abstract: Saare - Circa-SCOPE: high-throughput live single -cell imaging method for analys ... Read more Saare - Circa-SCOPE: high-throughput live single -cell imaging method for analysis of circadian clock resetting. Moshe- "Oligomeric states and much more using Mass Photometry”
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    Special Guest Seminar by Dr. Konstantin Feinberg

    Date:
    17
    Monday
    July
    2023
    Lecture / Seminar
    Time: 13:00-14:00
    Title: Schwann cells are key regulator of corneal epithelial renewal
    Location: Arthur and Rochelle Belfer Building for Biomedical Research
    Lecturer: Dr. Konstantin Feinberg
    Organizer: Department of Molecular Neuroscience
    Contact: ronitrosenberg@weizmann.ac.il
    Abstract: Purpose: Corneal sensory nerves protect the cornea from injury. They are also th ... Read more Purpose: Corneal sensory nerves protect the cornea from injury. They are also thought to stimulate limbal stem cells (LSCs) to produce transparent epithelial cells constantly, enabling vision. In other organs, Schwann cells (SCs) associated with tissue-innervating axon terminals mediate tissue regeneration. This study defines the critical role of the corneal axon-ensheathing SCs in homeostatic and regenerative corneal epithelial cell renewal. Methods: SC localization in the cornea was determined by in situ hybridization and immunohistochemistry with SC markers. In vivo SC visualization and/or ablation was performed in mice with inducible corneal SC-specific expression of TdTomato and/or Diphtheria toxin, respectively. The relative locations of SCs and LSCs was observed with immunohistochemical analysis of harvested genetically SC-pre-labeled mouse corneas with LSC-specific antibodies. The correlation between cornea-innervating axons and the appearance of SCs was ascertained using corneal denervation in rats. To determine the limbal niche cellular composition and gene expression changes associated with innervation-dependent epithelial renewal, single cell RNA sequencing (scRNA-Seq) of dissociated healthy, de-epithelized and enervated cornea limbi was performed. Results: We observed limbal enrichment of corneal axon-associated myelinating and non-myelinating SCs. Induced local genetic ablation of SCs, while leaving corneal sensory innervation intact, markedly inhibited corneal epithelial renewal. scRNA-seq analysis (i) highlighted the transcriptional heterogeneity of cells populating the limbal niche and (ii) identified transcriptional changes associated with corneal innervation and during wound healing that model potential regulatory paracrine interactions between SCs and LSCs. Conclusions: Limbal SCs are required for innervation-dependent corneal epithelial renewal.
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    Vision and AI

    Date:
    16
    Sunday
    July
    2023
    Lecture / Seminar
    Time: 12:15-13:15
    Title: Deep Learning Approaches for Inverse Problems in Computational Imaging and Chemistry
    Location: Jacob Ziskind Building
    Lecturer: Tomer Weiss
    Organizer: Department of Computer Science and Applied Mathematics
    Contact: karina.avadia@weizmann.ac.il
    Abstract: In this talk, I will present two chapters from my Ph.D. thesis. The core of my r ... Read more In this talk, I will present two chapters from my Ph.D. thesis. The core of my research focuses on methods that utilize the power of modern neural networks not only for their conventional tasks such as prediction or reconstruction, but rather use the information they “learned” (usually in the forms of their gradients) in order to optimize some end-task, draw insight from the data, or even guide a generative model. The first part of the talk is dedicated to computational imaging and shows how to apply joint optimization of the forward and inverse models to improve the end performance. We demonstrate these methods on three different tasks in the fields of Magnetic Resonance Imaging (MRI) and Multiple Input Multiple Output (MIMO) radar imaging. In the second part, we show a novel method for molecular inverse design that utilizes the power of neural networks in order to propose molecules with desired properties. We developed a guided diffusion model that uses the gradients of a pre-trained prediction model to guide a pre-trained unconditional diffusion model toward the desired properties. This method allows, in general, to transform any unconditional diffusion model into a conditional generative model.
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    Dendritic voltage imaging, excitability rules, and plasticity

    Date:
    10
    Monday
    July
    2023
    Lecture / Seminar
    Time: 12:45-13:45
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Adam E. Cohen
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Dr. Takashi Kawashima takashi.kawashima@weizmann.ac.il For accessibilit ... Read more Host: Dr. Takashi Kawashima takashi.kawashima@weizmann.ac.il For accessibility issues: naomi.moses@weizmann.ac.il
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    Abstract: Membrane voltage in dendrites plays a key role in mediating synaptic integration ... Read more Membrane voltage in dendrites plays a key role in mediating synaptic integration and activity-dependent plasticity; but dendritic voltages have been difficult to measure.  We developed molecular, optical, and computational tools for simultaneous optogenetic perturbations and voltage mapping in dendrites of neurons in acute slices and in awake mice.  These experiments revealed relations between dendritic ion channel biophysics and rules of synaptic integration and plasticity.  I will also describe tools for mapping large-scale network dynamics with millisecond time resolution, and for mapping brain-wide patterns of plasticity.
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    Cancer Imaging in the Clinics

    Date:
    10
    Monday
    July
    2023
    Lecture / Seminar
    Time: 12:15-13:00
    Location: Wolfson Building for Biological Research
    Lecturer: Prof. Dorith Shaham
    Organizer: Life Sciences
    Contact: levana.ayvazo@weizmann.ac.il
    Details: This lecture will be preceded by a lecture on “Cancer imaging Principles” ... Read more This lecture will be preceded by a lecture on “Cancer imaging Principles” Host: Zvi Livneh
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    Cancer Imaging Principles

    Date:
    10
    Monday
    July
    2023
    Lecture / Seminar
    Time: 11:15-12:00
    Location: Wolfson Building for Biological Research
    Lecturer: Prof. Rachel Katz-Brull
    Organizer: Life Sciences
    Contact: levana.ayvazo@weizmann.ac.il
    Details: Within the FGS course on Translational Cancer Research Host. Zvi Livneh

    Toward “reading” and “writing” neural population codes in the primate cortex

    Date:
    05
    Wednesday
    July
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Arthur and Rochelle Belfer Building for Biomedical Research
    Lecturer: Prof. Eyal Seidemann
    Organizer: Department of Brain Sciences
    Contact: devora.sofer@weizmann.ac.il
    Details: host: Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il
    Abstract: : A central goal of sensory neuroscience is to understand the nature of the neur ... Read more : A central goal of sensory neuroscience is to understand the nature of the neural code in sensory cortex to the point where we could “read” the code – i.e., account for a subject’s perceptual capabilities using solely the relevant cortical signals, and “write” the code – i.e., substitute sensory stimuli with direct cortical stimulation that is perceptually equivalent.  Distributed representations and topography are two key properties of primate sensory cortex. For example, in primary visual cortex (V1), a localized stimulus activates millions of V1 neurons that are distributed over multiple mm2, and neurons that are similarly tuned are clustered together at the sub-mm scale and form several overlaid topographic maps. The distributed and topographic nature of V1’s representation raises the possibility that in some visual tasks, the neural code in V1 operates at the topographic scale rather than at the scale of single neurons. If this were the case, then the fundamental unit of information would be clusters of similarly tuned neurons (e.g., orientation columns), and to account for the subjects’ performance, it would be necessary and sufficient to consider the summed activity of the thousands of neurons within each cluster. A long-term goal of my lab is to test the topographic population code hypothesis.  In this presentation, I will describe our progress toward developing a bi-directional, read-write, optical-genetic toolbox for directly testing this hypothesis in behaving macaques.
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    Siah3 acts upstream to Parkin to limit mitophagy and facilitate the apoptotic machinery during axonal pruning

    Date:
    04
    Tuesday
    July
    2023
    Lecture / Seminar
    Time: 10:00-11:00
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Omer Abraham
    Organizer: Department of Biomolecular Sciences
    Contact: levana.ayvazo@weizmann.ac.il
    Abstract: Spatial and temporal regulation of the apoptotic machinery is critical for the e ... Read more Spatial and temporal regulation of the apoptotic machinery is critical for the execution of multiple cellular events. Here we identify Seven In Absentia Homolog 3 (Siah3) as a new regulator of the cell death machinery during axonal pruning in developing mice. Sensory neurons from Siah3 KO mice exhibit delayed axonal degeneration and Caspase-3 activation in response to trophic deprivation. In agreement, the Siah3 KO mice display increased peripheral sensory innervation. Mechanistically, we show that Siah3 directly binds to the core mitophagy machinery protein Parkin, and, importantly, co-ablation of Prkn and Siah3 reverses the delay in axonal degeneration and Caspase-3 activation detected in Siah3 KO neurons. Strikingly, loss of Siah3 causes dramatic increase in axonal mitophagy upon trophic deprivation, suggesting that Siah3 is a positive regulator of axonal elimination acting by modulation of Parkin-mediated mitophagy. Overall, our results suggest that Parkin-mediated mitophagy restrains the apoptotic system by eliminating signaling mitochondria and reveal the role of mitochondrial signaling in axonal elimination.
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    Physics Colloquium

    Date:
    22
    Thursday
    June
    2023
    Colloquium
    Time: 11:15-12:30
    Title: Seeking the Closest Habitable-Zone Planets
    Location: Edna and K.B. Weissman Building of Physical Sciences
    Lecturer: Prof. Suvrath Mahadevan
    Organizer: Faculty of Physics
    Contact: eti.shalem@weizmann.ac.il
    Details: Coffee, Tea and more...
    Abstract: The discovery of planets capable of hosting biosignatures, and the characterizat ... Read more The discovery of planets capable of hosting biosignatures, and the characterization of the atmospheres of these planets, is a key and achievable goal in our lifetime. These goals require some of the most demanding precision spectroscopic and photometric measurements. I will discuss the instrumental challenges of detecting such planets with the Doppler radial velocity technique, and the evolution of the design of these instruments as they seek ever-tighter control of environmental parameters, and increased measurement precision. A suite of new technologies like frequency stabilized laser combs, low drift etalons, and deeper understanding of the detectors is enabling a new level of precision in radial velocity measurements - as well as illustrating new challenges. I will then discuss how the stars themselves are the remaining challenge, as magnetically driven processes create ‘stellar activity’ noise that can masquerade as planets and obfuscate their detection, and I highlight a few paths to mitigate this, along with some of the latest scientific results from the HPF and NEID instruments. I will discuss one iteration of a possible future, weaving its way from now through JWST individual and mini-population studies of planet atmospheres, large population studies with missions like ARIEL, the near-future of RV surveys, detection and characterization prospects with large ground-based, and the challenges and opportunities with future imaging and spectroscopic missions like LUVOIR and LIFE. The goal of discovering and characterizing terrestrial mass planets capable of hosting liquid water on their surfaces may now be within reach! But true understanding of the origin and meaning of the biosignatures we detect will likely require transdisciplinary research across multiple fields.
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    Crosstalk between the ECM and Proteases from destruction to regeneration

    Date:
    20
    Tuesday
    June
    2023
    -
    22
    Thursday
    June
    2023
    Conference
    Time: 08:00
    Location: The David Lopatie Conference Centre
    Contact: irit.sagi@weizmann.ac.il
    Crosstalk between the ECM and Proteases from destruction to regeneration Conference website

    Beyond the arcuate fasciculus: A multiplicity of language pathways in the human brain

    Date:
    13
    Tuesday
    June
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Michal Ben-Shachar
    Organizer: Department of Brain Sciences
    Contact: michal.ramot@weizmann.ac.il
    Abstract: Early models of the neurobiology of language targeted a single white matter path ... Read more Early models of the neurobiology of language targeted a single white matter pathway, the left arcuate fasciculus, as the critical language pathway in the human brain. Current models, supported by structural and functional imaging data, describe a more elaborate scheme of semi-parallel and bilateral white matter pathways that implement a variety of linguistic processes. In this talk, I will describe our current understanding of the language connectome, and highlight some recent additions to this scheme, including the frontal aslant tract and cerebellar pathways. I will expand on the role of ventral language pathways in extracting word structure, and on the role of dorsal and cerebellar pathways in mediating speech fluency and written text production. Our experimental approach combines diffusion MRI and targeted behavioral measurements, relating specific aspects of language processing with structural tract properties assessed in the same individual. Our findings show that cognitive associations with tractometry generalize across independent samples, languages, modalities and tasks. I will discuss the implications of our findings in the context of dual stream models of spoken and written language processing.
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    A link between viscoelastic mechanics and biochemical function of proteins

    Date:
    12
    Monday
    June
    2023
    Colloquium
    Time: 11:00-12:15
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Tsvi Tlusty
    Organizer: Faculty of Chemistry
    Contact: sarah.amzallag@weizmann.ac.il
    Abstract: Our starting point is the idea that specific regions in the protein evolve to b ... Read more Our starting point is the idea that specific regions in the protein evolve to become flexible viscoelastic elements facilitating conformational changes associated with function, especially allostery. Simple theories show how these regions can emerge through evolution and indicate that they are easily identified by amino acid rearrangement upon binding (i.e., shear motion). Surprisingly, AlphaFold can also identify such regions by computing the shear induced by a single or a few mutations. With these methods, we have tested the concept of shear and its functional relevance in a variety of proteins. I will present recent results from an experimental study of the enzyme guanylate kinase linking shear, large scale motions, and catalytic function. Altogether, the present findings paint a physical picture of proteins as viscoelastic machines with sequence encoded specifications, and we will discuss its general implications for understanding proteins and designing new ones.
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    A link between viscoelastic mechanics and biochemical function of proteins Colloquium website

    Reprogramming the topology of the nociceptive circuit in C. elegans reshapes sexual behavior

    Date:
    12
    Monday
    June
    2023
    Lecture / Seminar
    Time: 11:00-12:15
    Location: Arthur and Rochelle Belfer Building for Biomedical Research
    Lecturer: Vladyslava Pechuk
    Organizer: Department of Brain Sciences
    Contact: devora.sofer@weizmann.ac.il
    Details: Student Seminar Ph.D. Thesis Defense
    Abstract: The effect of the detailed connectivity of a neural circuit on its function and ... Read more The effect of the detailed connectivity of a neural circuit on its function and the resulting behavior of the organism, is a key question in many neural systems Here, I study the circuit for nociception in C elegans which is composed of the same neurons in the two sexes, that are wired differently I set out to elucidate how the topological design of a compact neuronal circuit affects its behavioral output, how genetic sex affects the connectivity and dynamics of a circuit, and how specific circuit components orchestrate together to establish the behavioral sexual dimorphism I used behavioral assays, optogenetics calcium and glutamate imaging, measurement of protein expression, artificial connectivity, molecular and genetic tools, and show that the nociceptive sensory neurons respond similarly in the two sexes, yet the animals display sexually dimorphic behaviors to the same aversive stimuli To uncover the role of the downstream network topology in shaping behavior, I measured the neuronal activity of a key interneuron, and found dimorphic responses to the stimulus as well as dimorphic intrinsic basal interneuron activity I then showed that neuron specific genetic sex plays a role in shaping connectivity and circuit dynamics, and proceed to an artificial subtle synaptic rewiring which flips behavior between sexes Interestingly, when presented with aversive cues, rewired males were compromised in finding mating partners, suggesting that network topologies that enable efficient avoidance of noxious cues have a reproductive " My results present a deconstruction of the design of a neural circuit that controls sexual behavior, and how to reprogram it
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    Vision and AI

    Date:
    08
    Thursday
    June
    2023
    Lecture / Seminar
    Time: 12:15-13:15
    Title: Imagic: Text-Based Real Image Editing with Diffusion Models
    Location: Jacob Ziskind Building
    Lecturer: Shiran Zada
    Organizer: Department of Computer Science and Applied Mathematics
    Contact: karina.avadia@weizmann.ac.il
    Abstract: Text-conditioned image editing has recently attracted considerable interest. How ... Read more Text-conditioned image editing has recently attracted considerable interest. However, most methods are currently either limited to specific editing types (e.g., object overlay, style transfer), or apply to synthetically generated images, or require multiple input images of a common object. In this paper we demonstrate, for the very first time, the ability to apply complex (e.g., non-rigid) text-guided semantic edits to a single real image. For example, we can change the posture and composition of one or multiple objects inside an image, while preserving its original characteristics. Our method can make a standing dog sit down or jump, cause a bird to spread its wings, etc. — each within its single high-resolution natural image provided by the user. Contrary to previous work, our proposed method requires only a single input image and a target text (the desired edit). It operates on real images, and does not require any additional inputs (such as image masks or additional views of the object). Our method, which we call "Imagic", leverages a pre-trained text-to-image diffusion model for this task. It produces a text embedding that aligns with both the input image and the target text, while fine-tuning the diffusion model to capture the image-specific appearance. We demonstrate the quality and versatility of our method on numerous inputs from various domains, showcasing a plethora of high quality complex semantic image edits, all within a single unified framework
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    Local and long-range inputs contributing to sequence generation in the zebra finch

    Date:
    06
    Tuesday
    June
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Arthur and Rochelle Belfer Building for Biomedical Research
    Lecturer: Prof. Michael A. Long
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Dr. Yarden Cohen Yarden.J.Cohen@weizmann.ac.il tel: 5138 For accessibi ... Read more Host: Dr. Yarden Cohen Yarden.J.Cohen@weizmann.ac.il tel: 5138 For accessibility isssues:naomi.moses@weizmann.ac.il
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    Abstract: : A central question in neuroscience is how local processing and long-range infl ... Read more : A central question in neuroscience is how local processing and long-range influences work together to create behaviorally relevant neural dynamics. We address this issue by examining the song control pathway in the zebra finch. We find sufficient synaptic information is present in a key cortical structure to enable propagation of song-related sequences. We further demonstrate that long-range inputs from the motor thalamus can engage this circuitry in the service of behavior and large-scale brain synchronization. Our findings suggest that thalamic inputs may play an important initiating role for behaviorally-relevant cortical activity across species.
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    Chemical and Biological Physics Guest Seminar

    Date:
    06
    Tuesday
    June
    2023
    Lecture / Seminar
    Time: 10:00-11:00
    Title: Materials with a twist: atomically controlled interfaces for clean energy
    Location: Perlman Chemical Sciences Building
    Lecturer: Prof Magali Lingenfelder
    Organizer: Department of Chemical and Biological Physics
    Contact: ron.naaman@weizmann.ac.il
    Abstract: Our society faces a critical challenge in shifting from a reliance on carbon-bas ... Read more Our society faces a critical challenge in shifting from a reliance on carbon-based energy to sustainable renewable sources. A key step towards achieving clean energy lies in developing efficient catalysts that can convert chemical energy into electricity or use electrons to generate chemical energy. In our research group, we tackle these challenges by creating customized materials that draw inspiration from nature (biomimicry) and combine principles from interfacial chemistry and surface physics. For this presentation, I focus on the process of photosynthesis as inspiration for the design, characterization, and dynamic nature of functional interfaces that drive energy conversion processes such as CO2 electroreduction and water splitting. I will also discuss the application of cutting-edge scanning probe microscopy, which allows us to visualize dynamic electrochemical processes at the nanoscale (operando imaging). Additionally, I will highlight our use of unconventional strategies that leverage chiral molecules and abundant two-dimensional materials to enhance electrocatalytic conversion processes. (References : Nanoletters, 2021, 21, 2059; Nature Comm., 2022, 13, 3356, IJC 62, 11, 2022).
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    Volatile cortical working memory representations crystalize with practice

    Date:
    01
    Thursday
    June
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Arthur and Rochelle Belfer Building for Biomedical Research
    Lecturer: Prof. Peyman Golshani
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host-Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il For accessibility issues: n ... Read more Host-Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il For accessibility issues: naomi.moses@weizmann.ac.il
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    Abstract: Working memory (WM), the process through which information is transiently mainta ... Read more Working memory (WM), the process through which information is transiently maintained and manipulated over a brief period of time, is essential for most cognitive functions. However, the mechanisms underlying the generation and stability of WM neuronal representations at the population level remain elusive. To uncover these mechanisms, we trained head-fixed mice to perform  an olfactory working memory task and used optogenetics to delineate circuits causal for behavioral performance. We used mesoscopic and light bead  two photon imaging to record from up to 35,000 secondary motor cortical neurons simulataneously across multiple days and show differential stabilization of different task parameters with learning and practice of the task. We find that cortical working memory representations causal for task performance are highly volatile but only stabilize after multiple days of practice well after task learning. We hypothesize that representational drift soon after learning may allow for higher levels of flexibility for new task rules.  I will also review some of the new open-source tools developed for large-scale imaging of neural activity patterns in freely behaving animals.
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    Vision and AI

    Date:
    01
    Thursday
    June
    2023
    Lecture / Seminar
    Time: 12:15-13:15
    Title: Spaceborne multi-view computational tomography (CT)
    Location: Jacob Ziskind Building
    Lecturer: Yoav Schechner
    Organizer: Department of Computer Science and Applied Mathematics
    Contact: karina.avadia@weizmann.ac.il
    Abstract: We describe new computer vision tasks stemming from upcoming multiview tomograph ... Read more We describe new computer vision tasks stemming from upcoming multiview tomography from space. Solutions involve both novel imaging hardware and computational algorithms, based on machine learning and differential rendering. This can transform climate research and medical X-ray CT. The key idea is that advanced computing can enable computed tomography of volumetric scenes, based scattered radiation. We describe an upcoming space mission (CloudCT, funded by the ERC). It has 10 nano-satellites that will fly in an unprecedented formation, to capture the same scene (cloud fields) from multiple views simultaneously, using special cameras. The satellites and cameras are built now. They - and the algorithms - are specified to meet computer vision tasks, including geometric and polarimetric self-calibration in orbit, and estimation of 3D volumetric distribution of matter and microphysical properties. Deep learning and differential rendering enable analysis to scale to big data downlinked from orbit. Core ideas are generalized for medical X-ray imaging, to enable significant reduction of dose and acquisition time, while extracting chemical properties per voxel. The creativity of the computer vision and graphics communities can assist in critical needs for society, and this talk points out relevant challenges.
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    Cognitive neuroscience of learning and memory in human infants

    Date:
    30
    Tuesday
    May
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Nick Turk-Browne
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host- Dr. Michal Ramot michal.ramot@weizmann.ac.il For accessibility issues: ... Read more Host- Dr. Michal Ramot michal.ramot@weizmann.ac.il For accessibility issues: naomi.moses@weizmann.ac.il
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    Abstract: In this talk, I will present the approach my lab has developed for performing fM ... Read more In this talk, I will present the approach my lab has developed for performing fMRI studies in awake infants during cognitive tasks. I will share some of our recent studies and highlight some of the big open questions that remain to be addressed, with potential to reveal the brain systems underlying how infants perceive and attend to their environment, why infants are such proficient learners, and why we all have amnesia for infant experiences. Despite countless limitations and challenges at present, this work suggests that awake infant fMRI could become more feasible, useful, and ubiquitous in cognitive neuroscience.
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    In-Vivo Imaging Technologies for Pre-Clinical Research

    Date:
    24
    Wednesday
    May
    2023
    Lecture / Seminar
    Time: 13:00-14:00
    Title: Spotlight on Science series
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Inbal Biton
    Contact: ayelet.vilan@weizmann.ac.il

    Machine Learning and Statistics Seminar

    Date:
    24
    Wednesday
    May
    2023
    Lecture / Seminar
    Time: 11:15-12:30
    Title: Cycle-edge message passing for group and non-group synchronization
    Location: Jacob Ziskind Building
    Lecturer: Prof. Gilad Lerman
    Organizer: Department of Computer Science and Applied Mathematics
    Contact: karina.avadia@weizmann.ac.il
    Abstract: The general synchronization problem asks to recover states of objects from their ... Read more The general synchronization problem asks to recover states of objects from their corrupted relative measurements. When the states are represented by group elements (e.g. 3-D rotations or permutations) this problem is known as group synchronization. In several applications, the algebraic structure of the states is more complicated, for example, the states can be represented by partial permutations. The synchronization problem has many applications, in particular, to structure-from-motion (SfM), where one needs to estimate the 3D structure of a scene from a set of its projected 2D images. I will first describe a general framework for group synchronization, the Cycle-Edge Message Passing (CEMP), and then explain its generalization to non groups, by exemplifying the case of partial permutation synchronization. I will emphasize mathematical difficulties, review some mathematical guarantees for the proposed methods and also demonstrate an application. This is a joint work with Shaohan Li and Yunpeng Shi.
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    Exploring sex-specific regulation of aging and health

    Date:
    23
    Tuesday
    May
    2023
    Lecture / Seminar
    Time: 10:00-11:00
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Dr. Itamar Harel
    Organizer: Department of Biomolecular Sciences
    Contact: levana.ayvazo@weizmann.ac.il
    Abstract: Bio: Experimental biology of vertebrate aging and age-related diseases: http://h ... Read more Bio: Experimental biology of vertebrate aging and age-related diseases: http://harel-lab.com/ Itamar Harel received his PhD in developmental biology at the Weizmann Institute of Science, and then trained in aging research at Stanford University. In 2018 he joined the Department of Genetics at the Hebrew University as Assistant Professor. The Harel lab is exploring fundamental questions in aging biology, such as why is aging such a strong driver of disease? To address a major challenge in aging research, Itamar has developed a comprehensive genetic platform for rapid exploration of aging and disease in a naturally short-lived vertebrate. The findings by the Harel lab have clinical implications for developing new strategies for modeling and treating age-related diseases, and for developing pro-longevity interventions.
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    Ultrafast processes and the challenge of decoherence

    Date:
    22
    Monday
    May
    2023
    Colloquium
    Time: 11:00-12:15
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Eberhard K. U. Gross
    Organizer: Faculty of Chemistry
    Contact: sarah.amzallag@weizmann.ac.il
    Abstract: A prominent goal of present-day condensed-matter physics is the design of electr ... Read more A prominent goal of present-day condensed-matter physics is the design of electronic devices with ever faster switching times. As an example I will present the optically induced spin transfer between magnetic sublattices, the so-called OISTR effect, which allows the switching of magnetic textures on the scale of a femto-second or less. This effect was first predicted with real-time TDDFT and later confirmed in many experiments. To create from this effect a real-world device on has to face the problem of decoherence, i.e. the phenomenon that quantum systems tend to lose their quantumness due to interactions with the environment. For electrons, the principal source of decoherence is the non-adiabatic interaction with nuclear degrees of freedom, i.e. with an “environment” that cannot be removed. In fact, the paradigm of electronic-structure theory where electrons move in the static Coulomb potential of clamped nuclei, while useful in the ground state, is an idealization hardly ever satisfied in dynamical processes. Non-adiabaticity, i.e. effects of the coupled motion of electrons and nuclei beyond the Born-Oppenheimer approximation are found everywhere. In this lecture, the exact factorization will be presented as a universal approach to understand and, ultimately, control non-adiabatic effects, in particular decoherence, from an ab-initio perspective.
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    Ultrafast processes and the challenge of decoherence Colloquium website

    “ Programmatic and Deep Learning Analysis Pipelines for 4D-STEM Materials Science Experiments”

    Date:
    21
    Sunday
    May
    2023
    Lecture / Seminar
    Time: 11:00-12:00
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Dr. Colin Ophus
    Organizer: Department of Molecular Chemistry and Materials Science
    Contact: ana.naamat@weizmann.ac.il
    Abstract: Scanning transmission electron microscopy (STEM) is one of the most popular mate ... Read more Scanning transmission electron microscopy (STEM) is one of the most popular materials science methods to characterize the structure and chemistry of nanoscale samples, owing to its high resolution and many flexible operating modes. In a conventional STEM experiment, we focus the electron beam down to a probe from nanometer to sub-angstrom scale, and scan it over the sample surface while recording diffracted signals which are transmitted through the specimen. STEM can also record analytic signals such as x-rays generated by the electron beam to measure composition, or energy loss of the transmitted electrons to probe the electronic structure of samples. Conventional STEM imaging detectors experiments produce only a few intensity values at each probe position, but modern high-speed detectors allow us to measure a full 2D diffraction pattern, over a grid of 2D probe positions, forming a four dimensional (4D)-STEM dataset. These 4D-STEM datasets record information about the local phase, orientation, deformation, and other parameters, for both crystalline and amorphous materials. 4D-STEM datasets can contain millions of images and therefore require highly automated and robust software codes to extract the target properties. In this talk, I will introduce our open source py4DSTEM analysis toolkit, and show how we use these codes to perform data-intensive studies of material properties over functional length scales. I will also demonstrate some applications of modern machine learning tools, to perform measurements on electron diffraction patterns where property signals have been scrambled by multiple scattering of the electron beam.
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    New Frontiers in Cardiac and Vascular Biology

    Date:
    20
    Saturday
    May
    2023
    -
    24
    Wednesday
    May
    2023
    Conference
    Time: 08:00
    Location: The David Lopatie Conference Centre
    Organizer: The M.D. Moross Institute for Cancer Research,The Dimitris N. Chorafas Institute for Scientific Exchange
    Contact: karina.yaniv@weizmann.ac.il
    New Frontiers in Cardiac and Vascular Biology Conference website

    Non-invasive Methods for Extracting Microstructural Information from Human Tissues: Implementation in a Clinical MRI Scanner

    Date:
    18
    Thursday
    May
    2023
    Lecture / Seminar
    Time: 09:30-10:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Dr Analía Zwick
    Organizer: Clore Institute for High-Field Magnetic Resonance Imaging and Spectroscopy
    Contact: ana.naamat@weizmann.ac.il
    Abstract: Extracting quantitative information about tissue microstructure using non-invasi ... Read more Extracting quantitative information about tissue microstructure using non-invasive methods is an exceptional challenge in understanding disease mechanisms and enabling early diagnosis of pathologies. Magnetic Resonance Imaging (MRI) is a promising and widely used technique to achieve this goal, but it still provides low resolution to reveal details of the microstructure. Recently, we have developed methods to produce images with quantitative information about the microstructure based on selective probing of spin dephasing induced by molecular diffusion restriction in cavities of the tissue microstructure [1-3]. The feasibility of the theoretical method has been demonstrated so far by first-principles experiments and simulations on typical size distributions of white matter in the mouse brain [3]. As a next step towards practical implementation, we have implemented this method in clinical scanners [4]. In this work, I present the challenges and preliminary results of this implementation in both phantoms and human volunteers. These results open up a new avenue for MRI to advance in extracting quantitative, and fast microstructural information from images. [1] A. Zwick, D. Sueter, G. Kurizki, G. A. Álvarez, Phys. Rev. Applied 14, 024088, (2020). [2] M. Capiglioni, A. Zwick, P. Jiménez, G. A. Álvarez. Proc. Intl. Soc. Mag. Reson. Med. 29, 2036 (2021) [3] M. Capiglioni, A. Zwick, P. Jiménez and G. A. Álvarez, Phys. Rev. Applied 15, 014045 (2021). [4] E. Saidman, A. Zwick, S. Tambalo, T. Feiweier, J. Jovicich, G. A. Álvarez. Proc. Intl. Soc. Mag. Reson. Med. (2023)
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    Vision and AI

    Date:
    11
    Thursday
    May
    2023
    Lecture / Seminar
    Time: 12:15-13:15
    Title: Human Motion Diffusion Model
    Location: Jacob Ziskind Building
    Lecturer: Guy Tevet
    Organizer: Department of Computer Science and Applied Mathematics
    Contact: karina.avadia@weizmann.ac.il
    Abstract: Natural and expressive human motion generation is the holy grail of computer ani ... Read more Natural and expressive human motion generation is the holy grail of computer animation. It is a challenging task, due to the diversity of possible motion, human perceptual sensitivity to it, and the difficulty of accurately describing it. Therefore, current generative solutions are either low-quality or limited in expressiveness. Diffusion models, which have already shown remarkable generative capabilities in other domains, are promising candidates for human motion due to their many-to-many nature, but they tend to be resource hungry and hard to control. In this paper, we introduce Motion Diffusion Model (MDM), a carefully adapted classifier-free diffusion-based generative model for the human motion domain. MDM is transformer-based, combining insights from motion generation literature. A notable design-choice is the prediction of the sample, rather than the noise, in each diffusion step. This facilitates the use of established geometric losses on the locations and velocities of the motion, such as the foot contact loss. As we demonstrate, MDM is a generic approach, enabling different modes of conditioning, and different generation tasks. We show that our model is trained with lightweight resources and yet achieves state-of-the-art results on leading benchmarks for text-to-motion and action-to-motion.
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    Smell and our unconscious sense of self

    Date:
    10
    Wednesday
    May
    2023
    Lecture / Seminar
    Time: 13:00-14:00
    Location: Arthur and Rochelle Belfer Building for Biomedical Research
    Lecturer: Prof. Benjamin D. Young
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Abstract: Benjamin D. Young Ph.D. is an associate professor in philosophy and interdiscipl ... Read more Benjamin D. Young Ph.D. is an associate professor in philosophy and interdisciplinary neuroscience at the University of Nevada, Reno. Previously he held a Kreitman Post-Doctoral Fellowship in the Department of Brain and Cognitive Sciences at Ben-Gurion University, as well as Visiting Assistant Professorship and Post-Doctoral Fellowship in the Department of Cognitive Science at Hebrew University. He conducts empirically informed philosophical research with a particular emphasis on olfaction focusing on non-conceptual content, qualitative consciousness in the absence of awareness, and the perceptible objects of smell. His most recent projects include co-editing the textbook Mind, Cognition, and Neuroscience and the collection Theoretical Perspectives on Smell. Ben is finishing a book on smell tentatively titled Stinking Philosophy! and beginning to work on a book about the unconscious mind. Previously he showed how olfaction calls into question the general neuroscientific theories of consciousness and the relationship between access and phenomenal consciousness. Dr. Young’s current research extends this framework and examines the role that smell plays in allowing us to recognize our embodied material composition and what we can perceive about others from their smell both with and without subjective awareness. For more information about Ben’s research see https://www.unr.edu/philosophy/faculty-staff/benjamin-young
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    The unique life of the intrinsically disordered proteins (IDPs)

    Date:
    09
    Tuesday
    May
    2023
    Lecture / Seminar
    Time: 10:00-11:00
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Prof. Yosef Shaul
    Organizer: Department of Biomolecular Sciences
    Contact: levana.ayvazo@weizmann.ac.il
    Abstract: Over 20% of our proteins are intrinsically disordered (IDP/IDR). IDPs/IDRs regul ... Read more Over 20% of our proteins are intrinsically disordered (IDP/IDR). IDPs/IDRs regulate many aspects of the living cells. They are generally highly dynamic, modifiable, adaptable, and short-lived proteins. We have previously reported that IDPs/IDRs undergoing proteasomal degradation via 26S and 20S proteasomes, the latter in a ubiquitin-independent manner. In this seminar, I will show data on the mechanisms of their 20S-mediated degradation in vitro and in the cells. Using proteomic approaches, we have identified many IDPs/IDRs undergoing 20S proteasomal degradation, all bearing unique structural features shared by liquid-liquid phase separation (LLPS) proteins. Proteasomal live imaging further highlighted the intracellular proteasomal dynamics and LLPS formation.
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    Nature, nurture, and the neuroscience of parenthood

    Date:
    02
    Tuesday
    May
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Bianca Jones Marlin
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il tel: 6957 For accessibil ... Read more Host: Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il tel: 6957 For accessibility issues: naomi.moses@weizmann.ac.il
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    Abstract: Introduction: Bianca Jones Marlin, Ph.D. is a neuroscientist and Herbert and Flo ... Read more Introduction: Bianca Jones Marlin, Ph.D. is a neuroscientist and Herbert and Florence Irving Assistant Professor of Cell Research at the Zuckerman Institute at Columbia University in New York City. Her research investigates how organisms unlock innate behaviors at appropriate times, and how learned information is passed to subsequent generations via transgenerational epigenetic inheritance. Dr. Marlin combines neural imaging, behavior, and molecular genetics to uncover how learned behavior in the parent can become innate behavior in the offspring— work that promises to make a profound impact on societal brain health, mental well-being, and parenting. For more information about Dr. Marlin, visit www.biancajonesmarlin.com
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    Nature, nurture, and the neuroscience of parenthood

    Date:
    02
    Tuesday
    May
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Bianca Jones Marlin
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il tel: 6957 For accessibil ... Read more Host: Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il tel: 6957 For accessibility issues: naomi.moses@weizmann.ac.il
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    Abstract: Introduction: Bianca Jones Marlin, Ph.D. is a neuroscientist and Herbert and Flo ... Read more Introduction: Bianca Jones Marlin, Ph.D. is a neuroscientist and Herbert and Florence Irving Assistant Professor of Cell Research at the Zuckerman Institute at Columbia University in New York City. Her research investigates how organisms unlock innate behaviors at appropriate times, and how learned information is passed to subsequent generations via transgenerational epigenetic inheritance. Dr. Marlin combines neural imaging, behavior, and molecular genetics to uncover how learned behavior in the parent can become innate behavior in the offspring— work that promises to make a profound impact on societal brain health, mental well-being, and parenting. For more information about Dr. Marlin, visit www.biancajonesmarlin.com
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    Vision and AI

    Date:
    20
    Thursday
    April
    2023
    Lecture / Seminar
    Time: 12:15-13:15
    Title: Training Set Reconstruction and Single-Video Generation
    Location: Jacob Ziskind Building
    Lecturer: Niv Haim
    Organizer: Department of Computer Science and Applied Mathematics
    Contact: karina.avadia@weizmann.ac.il
    Abstract: Over the past decade, deep learning has made significant strides in the fields o ... Read more Over the past decade, deep learning has made significant strides in the fields of computer vision and machine learning. However, there is still a lack of understanding regarding how these machines store and utilize training samples to generalize to unseen data. In my thesis (guided by Prof. Irani), I investigated how neural networks encode training samples in their parameters and how such samples can sometimes be reconstructed. Additionally, I examined the capabilities of generative models in learning and generalizing from a single video. Specifically, I explored the effectiveness of patch-based methods and diffusion models in generating diverse output samples, and how such models can utilize the motion and dynamics of a single input video to learn and generalize.
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    Neurotechnology 2023: Precision Approaches for Studying and Treating the Brain

    Date:
    19
    Wednesday
    April
    2023
    -
    20
    Thursday
    April
    2023
    Conference
    Time: 08:00 - 20:30
    Location: The David Lopatie Conference Centre
    Contact: takashi.kawashima@weizmann.ac.il
    Neurotechnology 2023: Precision Approaches for Studying and Treating the Brain Conference website

    Navigation in larval zebrafish:strategies and internal representations

    Date:
    03
    Monday
    April
    2023
    Lecture / Seminar
    Time: 12:45-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Ruben Portugues
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Takashi Kawashima takashi.kawashima@weizmann.ac.il For accessibility is ... Read more Host: Takashi Kawashima takashi.kawashima@weizmann.ac.il For accessibility issues: naomi.moses@weizmann.ac.il
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    Abstract: Larval zebrafish can navigate their environment and seek conditions that meet th ... Read more Larval zebrafish can navigate their environment and seek conditions that meet their physiological needs. We refer to this process as homeostatic navigation. We use careful behavioral analysis, whole-brain imaging, and neuronal perturbations to identify the behavioral strategy and the neuronal circuitry that underlie this important behavior. In addition, I will recap recent studies from our lab, involving perceptual decision making and the identification of a heading direction network, that all together, provide insights into how the brain of this small vertebrate controls behavior across these various paradigms.
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    3D quantitative-amplified Magnetic Resonance Imaging (3D q-aMRI)

    Date:
    02
    Sunday
    April
    2023
    Lecture / Seminar
    Time: 16:30-17:30
    Location: Perlman Chemical Sciences Building
    Lecturer: Itamar Terem
    Organizer: Clore Institute for High-Field Magnetic Resonance Imaging and Spectroscopy
    Contact: ana.naamat@weizmann.ac.il
    Abstract: Changes in blood vessel pulsation and cerebrospinal fluid dynamics cause cyclic ... Read more Changes in blood vessel pulsation and cerebrospinal fluid dynamics cause cyclic deformation of the brain, which can be altered by neurological pathologies. Various MRI techniques are available to visualize and quantify pulsatile brain motion, but they have limitations. Amplified MRI (aMRI) is a promising new technique that can visualize pulsatile brain tissue motion by amplifying sub-voxel motion in cine MRI data, but it lacks the ability to quantify the sub-voxel motion field in physical units. Here a novel 3D quantitative aMRI (3D q-aMRI) post-processing algorithm is introduced that can visualize and quantify pulsatile brain motion. To validate the algorithm, we tested it on a 3D digital phantom and on healthy volunteers. We also acquired preliminary data on participants with Alzheimer's disease and healthy aging controls. The results show that 3D q-aMRI can accurately quantify sub-voxel motion (of 0.005 pixel size) and has potential diagnostic value in identifying disease-induced biomechanical differences.
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    Brain plasticity Regulation and Modulation. Neurobiology symposium in honor of Prof. Menahem Segal

    Date:
    29
    Wednesday
    March
    2023
    -
    30
    Thursday
    March
    2023
    Conference
    Time: 15:00 - 17:15
    Location: The David Lopatie Conference Centre
    Contact: ofer.yizhar@weizmann.ac.il
    Brain plasticity Regulation and Modulation. Neurobiology symposium in honor of Prof. Menahem Segal Conference website

    The neurobiological function of experience-regulated genomic enhancers From transcriptional mechanisms to control over synaptic plasticity and sensory processing

    Date:
    20
    Monday
    March
    2023
    Lecture / Seminar
    Time: 14:45-15:45
    Location: Max and Lillian Candiotty Building
    Lecturer: Ori Roethler Dr. Ivo Spiegel Lab
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details:
    Abstract: The brain consists of a mosaic of distinct cell-types with unique activity-regul ... Read more The brain consists of a mosaic of distinct cell-types with unique activity-regulated gene programs that can drive long-lasting changes in the function and structure of developing and matured neural circuits. However, the molecular mechanisms in specific neuronal subtypes underlying these cellular/circuit changes remain poorly understood and techniques for studying these molecular mechanisms in specific cell populations are still lacking. Genomic enhancers are thought to modulate specific sets of synapses by regulating experience-induced and cell-type specific transcription of genes that promote neural circuit plasticity. Nevertheless, this idea remains untested. Thus, here I set out to investigate the genomic mechanisms that control the experience-induced transcription of the Insulin-like growth factor 1 (Igf1) in disinhibitory VIP interneurons (INs) in the adult visual cortex and the cellular and circuit functions they underly. I found two cell-type specific sensory-induced enhancers that selectively drive sensory-induced Igf1 transcription. These enhancers homeostatically control the ratio between excitation and inhibition (E/I-ratio), thereby restricting the activity of VIP INs and preserving the response properties to visual stimuli.
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    Animal morphogenesis as a dynamical phase transition

    Date:
    20
    Monday
    March
    2023
    Colloquium
    Time: 11:00-12:15
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Erez Braun
    Organizer: Faculty of Chemistry
    Contact: sarah.amzallag@weizmann.ac.il
    Abstract: A remarkable hallmark of animal morphogenesis is the convergence of this dynamic ... Read more A remarkable hallmark of animal morphogenesis is the convergence of this dynamic process into a stereotypic viable organism. The current picture relies on biochemical patterning with a well-defined hierarchy of forward-driven processes. I will discuss the nature of developmental processes, arguing that morphogenesis is robust due to the synergistic dynamics of mechanical, biochemical and electrical processes. Hydra regeneration provides a unique experimental setup, allowing us to develop a physics framework for this pattern-formation process. We demonstrate that an external electric field can be tuned to drive morphogenesis in whole-body Hydra regeneration, backward and forward, around a critical point in a controlled manner. We show that calcium (Ca2+) fluctuations underlie Hydra morphogenesis. Utilizing an external electric field as a control, we study these fluctuations at the onset of morphogenesis showing their universal characteristics and their associations with the morphological dynamics. Our analysis shows that the Hydra's tissue resides near the onset of bistability and the external control modulates the dynamics near that onset. It paints a picture of morphogenesis analogous to a dynamical phase transition.
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    Gallery: Animal morphogenesis as a dynamical phase transition Gallery
    Animal morphogenesis as a dynamical phase transition Colloquium website

    Neuronal activity and noise in synaptic wiring specificity

    Date:
    16
    Thursday
    March
    2023
    Lecture / Seminar
    Time: 10:30-13:30
    Location: Nella and Leon Benoziyo Building for Brain Research
    Lecturer: Dr. Laura Andreae
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: ROOM 113 Host: Dr. Yoav Livneh yoav.livneh@weizmann.ac.il For accessibility ... Read more ROOM 113 Host: Dr. Yoav Livneh yoav.livneh@weizmann.ac.il For accessibility issues: naomi.moses@weizmann.ac.il
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    Abstract: The role of neuronal activity in the development of neurons and circuits remains ... Read more The role of neuronal activity in the development of neurons and circuits remains controversial. Historically, activity has been seen to be critical for the sculpting of connectivity patterns after the period of synapse formation, often pruning unused synapses and helping to maintain or grow active ones. We now have evidence that a specific type of activity, spontaneous transmitter release, in the past often regarded as simply 'noise', plays a role in synapse formation and the development of dendritic morphology at early stages in the developmental period. Using both in vitro and in vivo approaches in mice to manipulate spontaneous transmitter release and the postsynaptic receptors that detect it, we show that these effects are connection specific in the developing hippocampal circuit. Many of the key synaptic proteins involved are known to be mutated in severe neurodevelopmental disorders, indicating how important these early roles may be in healthy brain development.
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    Special seminar: Simultaneous Imaging of millions of Single cells with the Xenium In situ platform

    Date:
    14
    Tuesday
    March
    2023
    Lecture / Seminar
    Time: 10:00-11:00
    Location: Max and Lillian Candiotty Building
    Lecturer: Dr. Stephen Hague
    Organizer: Department of Life Sciences Core Facilities
    Contact: hadas.keren-shaul@weizmann.ac.il

    Spatiotemporal Resolution of Conformational Changes in Biomolecules by Pulsed Electron-Electron Double Resonance Spectroscopy

    Date:
    09
    Thursday
    March
    2023
    Lecture / Seminar
    Time: 09:30-10:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Dr. Tobias Hett
    Organizer: Clore Institute for High-Field Magnetic Resonance Imaging and Spectroscopy
    Contact: ana.naamat@weizmann.ac.il
    Abstract: Proteins are highly dynamic biomolecules that can undergo ligand-induced confor ... Read more Proteins are highly dynamic biomolecules that can undergo ligand-induced conformational changes, thus often playing a crucial role in biomolecular processes. For an in-depth understanding of protein function, the conversion of one conformational state into another has to be resolved over space and time. Pulsed electron-electron double resonance spectroscopy (PELDOR/DEER) in combination with site-directed spin labelling (SDSL) is a powerful tool for obtaining distributions of interspin distances in proteins [1, 2]. It allows for measurements with Angstrom precision, but it cannot directly determine the time scale and the mechanism of the conformational change. However, coupling PELDOR with rapid freeze-quench techniques adds the time axis to the distance distribution and thus permits studying conformational changes with temporal resolution. Here, we show that the combination of Microsecond Freeze-Hyperquenching (MHQ) [3] and PELDOR resolves ligand-triggered conformational changes in proteins on the Angstrom length and microsecond time scale. It allows taking snapshots along the trajectory of the conformational change by rapid quenching within aging times of 82-668 μs, and it is applicable at protein amounts down to 7.5 nmol (75 μM, 100 μL) per time point. We applied MHQ/PELDOR to the cyclic nucleotide-binding domain (CNBD) of the MloK1 channel from Mesorhizobium loti, which undergoes a conformational change upon binding of cyclic adenosine monophosphate (cAMP). We observed a gradual population shift from the apo to the holo state on the microsecond time scale, but no distinct conformational intermediates (Fig. 1a, b). [4] Figure 1: a) Interspin distance distributions obtained at different aging times and b) the corresponding fractions of apo and holo state. c) Free-energy profile of the ligand-induced conformational change. Corroborated by measurements of ligand-binding kinetics and molecular dynamics (MD) simulations, we interpret the data in terms of a dwell time distribution. The transitions across the free-energy barriers (Fig. 1c) i.e., ligand binding and the conformational change, are on the nanosecond time scale and thus below the time resolution of the MHQ device. However, the dwell time of the apo state in complex with the cAMP ligand is in the microsecond range and can be monitored by MHQ/PELDOR. [4] Literature: [1] A.D. Milov et al., Fiz. Tverd. Tela 1981, 23, 975-982. [2] G. Jeschke, Annu. Rev. Phys. Chem. 2012, 63, 419-446. [3] A.V. Cherepanov et al., Biochim. Biophys. Acta 2004, 1656, 1-31. [4] T. Hett et al., J. Am. Chem. Soc. 2021, 143, 6981-6989.
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    "Uncovering novel Cardiac Biochemistry from large human cohort studies"

    Date:
    05
    Sunday
    March
    2023
    Lecture / Seminar
    Time: 09:30-10:30
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Dr. Michael Elgart
    Organizer: Department of Biomolecular Sciences
    Contact: levana.ayvazo@weizmann.ac.il
    Abstract: "Mechanistic studies of human disease-related biochemistry typically rely on ani ... Read more "Mechanistic studies of human disease-related biochemistry typically rely on animal models to devise hypotheses and conduct functional testing. The success of this approach is conditioned on conservation of biochemical pathways between humans and the animal, and the ability of the model to recapitulate key features of human disease which is rare . This is rarely true for complex human conditions such as neurological and cardiovascular diseases. In the absence of a suitable animal model, the study of human diseases has been limited to analysis of associations between clinical outcomes and physiological and/or molecular traits. Using the recent availability of multi-dimensional data from very large human cohorts we have devised principally novel approaches to identify associations of biochemicals with existing biochemical pathways in the context of human disease. This new ability allowed us to formulate a new paradigm akin to Koch postulates but applied to mechanistic component identification of complex disease. It relies on identification of putative disease drivers from human data, verification of these findings in animal models, deriving novel mechanism-related associations from the animal model, and back-testing the new associations in human data. This workflow is much more likely to correctly reflect shared biology between the animal model and humans as it pertains to disease, and thus serve as a true tool for mechanistic biochemical research."
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    Optical Imaging and image quantification across scales

    Date:
    02
    Thursday
    March
    2023
    Lecture / Seminar
    Time: 09:00-10:00
    Location: Max and Lillian Candiotty Building
    Lecturer: Dr. Sefi Addadi
    Organizer: Department of Life Sciences Core Facilities
    Contact: yoseph.addadi@weizmann.ac.il

    Horizontal cells of the vertebrate retina – From channels to functions

    Date:
    28
    Tuesday
    February
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Andreas Feigenspan
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Abstract: Visual information is transferred at the ribbon synapse – the first synapse of ... Read more Visual information is transferred at the ribbon synapse – the first synapse of the visual system – from photoreceptors to bipolar cells and horizontal cells. Whereas multiple bipolar cell types form parallel channels of vertical signal transfer to ganglion cells, the output neurons of the retina, the molecular basis of horizontal function within the retinal circuitry remains enigmatic. We have combined electrophysiology and calcium imaging with immunocytochemistry as well as single-cell RNA-sequencing and machine-learning approaches to establish a detailed map of voltage- and ligand-gated ion channels expressed by horizontal cells of the vertebrate retina. Our results provide a characteristic molecular signature of ionotropic glutamate receptors responsible for converting photoreceptor signals into postsynaptic membrane potential changes. We suggest that local information processing in horizontal cell dendrites is accompanied by cell-wide signals mediated by activation of voltage-gated calcium and sodium channels, which generate spike-like events. Comparison across different vertebrate species indicates a common theme of ion channel expression with variations based on evolutionary distance. Correlating the spatio-temporal pattern of horizontal cell activity with the biophysical properties of ion channels and neurotransmitter receptors will provide a better understanding of early signal processing in the vertebrate retina.
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    Sensory processing in the whisker system of awake, behaving mice

    Date:
    27
    Monday
    February
    2023
    Lecture / Seminar
    Time: 14:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Rasmus Petersen
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Prof. Ehud Ahissar ehud.ahissar@weizmann.ac.il For accessibility issues ... Read more Host: Prof. Ehud Ahissar ehud.ahissar@weizmann.ac.il For accessibility issues: naomi.moses@weizmann.ac.il
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    Abstract: The ultimate purpose of sensory systems is to drive behaviour.  Yet the bulk of ... Read more The ultimate purpose of sensory systems is to drive behaviour.  Yet the bulk of textbook knowledge of sensory systems comes from experiments on anaesthetised animals where the motor systems are disengaged.  The broad aim of our research is to investigate the neural basis of sensation in the behaving brain.  In this talk, I will present work that addresses two fundamental issues concerning the function of primary sensory cortex.  First, what role does Sensory Adaptation play under awake, behaving conditions?  Second, to what extent does behaviour modulate sensory processing in freely moving animals?
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    How the brain transforms sensory input into action

    Date:
    21
    Tuesday
    February
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Lecturer: Prof. Tom Mrsic-Flogel
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Zoom link: https://weizmann.zoom.us/j/96661197731?pwd=QTM4dHcvUFovTjZRU1BUVGhnW ... Read more Zoom link: https://weizmann.zoom.us/j/96661197731?pwd=QTM4dHcvUFovTjZRU1BUVGhnWjZHZz09 Meeting ID: 966 6119 7731 Password: 814783 Host: Dr. Ivo Spiegel
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    Sensitizing P-selectin-expressing brain malignancies to immune checkpoint modulators

    Date:
    16
    Thursday
    February
    2023
    Lecture / Seminar
    Time: 14:00-15:00
    Location: Max and Lillian Candiotty Building
    Lecturer: Prof. Ronit Satchi-Fainaro, PhD
    Organizer: Dwek Institute for Cancer Therapy Research
    Contact: michal.av@weizmann.ac.il
    Details: https://weizmann.zoom.us/j/5065402023?pwd=a3Z6KzRCU0xJaUFoM2Y5emZwZm1oZz09

    Special Guest Seminar

    Date:
    16
    Thursday
    February
    2023
    Lecture / Seminar
    Time: 10:00-11:00
    Title: Inter-organelle communication pathways revealed by imaging
    Location: Arthur and Rochelle Belfer Building for Biomedical Research
    Lecturer: Prof. Jennifer Lippincott-Schwartz
    Organizer: Department of Molecular Genetics
    Contact: evi.ben-ami@weizmnn.ac.il

    Molecular MRI of brain function

    Date:
    16
    Thursday
    February
    2023
    Lecture / Seminar
    Time: 09:30-10:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Alan Jasanoff
    Organizer: The Helen and Martin Kimmel Institute for Magnetic Resonance Research
    Contact: ananaamat@gmail.com
    Abstract: Understanding the neural bases of behavior and cognition requires determining ho ... Read more Understanding the neural bases of behavior and cognition requires determining how mechanistically distinct processing elements combine to carry out brain function at an integrated level. In this talk, I will introduce some of our laboratory’s efforts to address this goal using a combination of molecular sensors with noninvasive wide-field imaging. In the first part of the talk, I will discuss how workhorse optical neuroimaging approaches have inspired the design of molecular MRI probes for sensing physiological variables. Some of these probes detect light, providing a means for deep-tissue MRI-assisted optical imaging. I will next introduce an alternative molecular imaging concept inspired by widely used hemodynamic functional MRI techniques. By reengineering some of the proteins and peptides involved in neurovascular coupling, it is possible to create sensitive probes for a variety of neurobiological targets. I will illustrate how this strategy can be used to elucidate patterns of information flow and neurochemically specific functional connectivity in brain circuitry, with anticipated utility for deciphering mechanisms of learning and sensory processing in rodents and primates.
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    Cerebral Cortex Connectomics

    Date:
    14
    Tuesday
    February
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Moritz Helmstaedter
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Prof. Yaniv Ziv yaniv.ziv@weizmann.ac.il For accessibility issues:naomi ... Read more Host: Prof. Yaniv Ziv yaniv.ziv@weizmann.ac.il For accessibility issues:naomi.moses@weizmann.ac.il
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    Abstract: Dept of Connectomics Max Planck Institute for Brain Research Frankfurt ... Read more Dept of Connectomics Max Planck Institute for Brain Research Frankfurt
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    Understanding nutritional impact on bone development and quality

    Date:
    12
    Sunday
    February
    2023
    Lecture / Seminar
    Time: 15:00-16:00
    Location: Arthur and Rochelle Belfer Building for Biomedical Research
    Lecturer: Prof. Efrat Monsonego Ornan
    Organizer: Life Sciences
    Contact: yael.kuperman@weizmann.ac.il

    Mapping brainstem nuclei structure and connectivity in health and disease 

    Date:
    07
    Tuesday
    February
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Dr. Marta Bianciardi
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Dr. Michal Ramot michal.ramot@weizmann.ac.il For accessibility issues c ... Read more Host: Dr. Michal Ramot michal.ramot@weizmann.ac.il For accessibility issues contact:naomi.moses@weizmann.ac.il
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    Abstract: Brainstem nuclei in humans play a crucial role in vital functions, such as arous ... Read more Brainstem nuclei in humans play a crucial role in vital functions, such as arousal, autonomic homeostasis, sensory and motor relay, nociception, and sleep and have been implicated in a vast array of brain pathologies, including disorders of consciousness, sleep disorders, autonomic disorders, pain, Parkinson’s disease and other motor disorders. Yet, an in vivo delineation of most human brainstem nuclei location and connectivity using conventional imaging has been elusive because of limited sensitivity and contrast for detecting these small regions using standard neuroimaging methods. In this talk, Dr. Bianciardi will present the probabilistic atlas and connectome of 31 brainstem nuclei of the arousal, motor, autonomic and sensory systems developed by her team in healthy living humans using structural, functional and diffusion-based MRI at 7 Tesla. She will also show the translatability of 7 Tesla connectivity results to conventional 3 Tesla imaging. Dr Bianciardi will conclude her seminar by presenting the first translational application of the brainstem nuclei atlas to investigate arousal and motor mechanisms in traumatic coma and premanifest synucleinopathy.
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    Faculty Seminar

    Date:
    02
    Thursday
    February
    2023
    Lecture / Seminar
    Time: 12:45-14:00
    Title: Computational Imaging for Scientific Discovery: From Cloud Physics to Black Holes Dynamics
    Location: Jacob Ziskind Building
    Lecturer: Aviad Levis
    Organizer: Department of Computer Science and Applied Mathematics
    Contact: karina.avadia@weizmann.ac.il
    Details: Imaging plays a key role in advancing science, from revealing the internal struc ... Read more Imaging plays a key role in advancing science, from revealing the internal structure of clouds to providing the first visual evidence of a black hole. While both examples come from different imaging systems, they illustrate what can be achieved with modern computational approaches. Computational imaging combines concepts from physics, machine learning, and signal processing to reveal hidden structures at the smallest and largest of scales. In this talk, I will highlight how peeling away layers of the underlying physics leads to a spectrum of algorithms targeting new scientific discoveries. I will focus on the Event Horizon Telescope (EHT), a unique computational camera with the goal of imaging the glowing fluid surrounding supermassive black holes. In May of 2022, the EHT collaboration revealed the first images of the black hole at the center of our galaxy: Sagittarius A* (Sgr A*). These images were computationally reconstructed from measurements taken by synchronized telescopes around the globe. While images certainly offer interesting insights, looking toward the future, we are developing new computational algorithms that aim to go beyond a 2D image. For example, could we use EHT observations to recover the dynamic evolution or even the 3D structure? We tackle these challenges by integrating emerging AI concepts with physics models. Our hope is that in the not-too-distant future, these new and exciting prospects will enable scientific discovery and even provide a glimpse into the very nature of space-time itself in our galaxy's most extreme environment. Bio: Aviad Levis is a postdoctoral scholar in the Department of Computing and Mathematics at Caltech, working with Prof. Katherine Bouman. Currently, as part of the Event Horizon Telescope collaboration, his work focuses on developing novel computational methods for imaging black hole dynamics. Prior to that, he received his Ph.D. (2020) from the Technion and his B.Sc. (2013) from Ben-Gurion University. Notably, his Ph.D. research into 3D remote sensing of clouds is a key enabler in a novel interdisciplinary space mission (CloudCT) funded by the ERC and led by Yoav Schechner, Ilan Koren, and Klaus Schilling. Aviad is a recipient of the Zuckerman and the Viterbi postdoctoral fellowships.
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    Abstract: Imaging plays a key role in advancing science, from revealing the internal struc ... Read more Imaging plays a key role in advancing science, from revealing the internal structure of clouds to providing the first visual evidence of a black hole. While both examples come from different imaging systems, they illustrate what can be achieved with modern computational approaches. Computational imaging combines concepts from physics, machine learning, and signal processing to reveal hidden structures at the smallest and largest of scales. In this talk, I will highlight how peeling away layers of the underlying physics leads to a spectrum of algorithms targeting new scientific discoveries. I will focus on the Event Horizon Telescope (EHT), a unique computational camera with the goal of imaging the glowing fluid surrounding supermassive black holes. In May of 2022, the EHT collaboration revealed the first images of the black hole at the center of our galaxy: Sagittarius A* (Sgr A*). These images were computationally reconstructed from measurements taken by synchronized telescopes around the globe. While images certainly offer interesting insights, looking toward the future, we are developing new computational algorithms that aim to go beyond a 2D image. For example, could we use EHT observations to recover the dynamic evolution or even the 3D structure? We tackle these challenges by integrating emerging AI concepts with physics models. Our hope is that in the not-too-distant future, these new and exciting prospects will enable scientific discovery and even provide a glimpse into the very nature of space-time itself in our galaxy's most extreme environment. // Bio: Aviad Levis is a postdoctoral scholar in the Department of Computing and Mathematics at Caltech, working with Prof. Katherine Bouman. Currently, as part of the Event Horizon Telescope collaboration, his work focuses on developing novel computational methods for imaging black hole dynamics. Prior to that, he received his Ph.D. (2020) from the Technion and his B.Sc. (2013) from Ben-Gurion University. Notably, his Ph.D. research into 3D remote sensing of clouds is a key enabler in a novel interdisciplinary space mission (CloudCT) funded by the ERC and led by Yoav Schechner, Ilan Koren, and Klaus Schilling. Aviad is a recipient of the Zuckerman and the Viterbi postdoctoral fellowships.
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    My adventures in the rat interactive foraging facility (RIFF)

    Date:
    31
    Tuesday
    January
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Eli Nelken
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host-Dr. Michal Ramot michal.ramot@weizmann.ac.il For accessibility issues:na ... Read more Host-Dr. Michal Ramot michal.ramot@weizmann.ac.il For accessibility issues:naomi.moses@weizmann.ac.il
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    Abstract: We developed an arena (called colloquially the RIFF) for jointly studying behavi ... Read more We developed an arena (called colloquially the RIFF) for jointly studying behavior and neural activity in freely-behaving rats. The RIFF operates as a state machine, allowing us to implement a large number of different behaviors as Markov Decision Processes and therefore to analyze much of the data within the theoretical framework of reinforcement learning. In the studies I will show here, we recorded neural activity from auditory cortex while rats performed auditory-guided behavior. We observed an intricate interplay between behavior and neural activity that was much richer than we expected.
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    "Molecules in a Quantum-Optical Flask"

    Date:
    25
    Wednesday
    January
    2023
    Lecture / Seminar
    Time: 11:00-12:00
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Dr. Tal Schwartz
    Organizer: Department of Molecular Chemistry and Materials Science
    Contact: ana.naamat@weizmann.ac.il
    Abstract: "Molecules in a Quantum-Optical Flask" When confined to small dimensions, the ... Read more "Molecules in a Quantum-Optical Flask" When confined to small dimensions, the interaction between light and matter can be enhanced up to the point where it overcomes all the incoherent, dissipative processes. In this "strong coupling" regime the photons and the material start to behave as a single entity, having its own quantum states and energy levels. In this talk I will discuss how such cavity-QED effects can be used in order to control material properties and molecular processes. This includes, for example, modifying photochemical reactions [1], enhancing excitonic transport up to ballistic motion close to the light-speed [2-3] and potentially tailoring the mesoscopic properties of organic crystals, by hybridizing intermolecular vibrations with electromagnetic THz fields [4-5]. 1. J. A. Hutchison, T. Schwartz, C. Genet, E. Devaux, and T. W. Ebbesen, "Modifying Chemical Landscapes by Coupling to Vacuum Fields," Angew. Chemie Int. Ed. 51, 1592 (2012). 2. G. G. Rozenman, K. Akulov, A. Golombek, and T. Schwartz, "Long-Range Transport of Organic Exciton-Polaritons Revealed by Ultrafast Microscopy," ACS Photonics 5, 105 (2018). 3. M. Balasubrahmaniyam, A. Simkovich, A. Golombek, G. Ankonina, and T. Schwartz, "Unveiling the mixed nature of polaritonic transport: From enhanced diffusion to ballistic motion approaching the speed of light," arXiv:2205.06683 (2022). 4. R. Damari, O. Weinberg, D. Krotkov, N. Demina, K. Akulov, A. Golombek, T. Schwartz, and S. Fleischer, "Strong coupling of collective intermolecular vibrations in organic materials at terahertz frequencies," Nat. Commun. 10, 3248 (2019). 5. M. Kaeek, R. Damari, M. Roth, S. Fleischer, and T. Schwartz, "Strong Coupling in a Self-Coupled Terahertz Photonic Crystal," ACS Photonics 8, 1881 (2021).
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    Naturalistic approaches for studying social interactions, communication and language at cellular scale

    Date:
    24
    Tuesday
    January
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Ziv Williams
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host-Dr. Michal Ramot michal.ramot@weizmann.ac.il Contact for accessibility i ... Read more Host-Dr. Michal Ramot michal.ramot@weizmann.ac.il Contact for accessibility issues-naomi.moses@weizmann.ac.il
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    Abstract: Social interactions are remarkably dynamic, requiring individuals to understand ... Read more Social interactions are remarkably dynamic, requiring individuals to understand not only how their behavior may affect others but also how others may respond in return. In humans, social interactions are also often dominated by processes such as language and theory of mind which allow us to communicate complex thoughts and beliefs. Understanding the basic cellular processes that underlie social behavior or by which individuals communicate, however, has remained a challenge. Here, I describe naturalistic approaches developed in animals and humans that aim of investigating these questions. First, by developing an ethologically based group task in three-interacting rhesus macaques, I describe representations of other’s behavior by neurons in the prefrontal cortex, reflecting the other’s identities, their interactions, actions, and outcomes. I also show how these cells collectively represent the interaction between specific group members and how they enable mutually beneficial social behavior. Second, by recording from neurons in the human prefrontal cortex during language-based tasks, I describe neurons that reliably encode information about others’ beliefs across richly varying scenarios and that distinguish self- from other-belief-related representations. By further following their encoding dynamics, I also describe how these cells represent the contents of the others’ beliefs and predict whether they are true or false. Finally, I describe how these cell ensembles track linguistic information during natural speech processing and how language can be used to ask specific questions about the single-cellular constructs that underlie social reasoning. Together, these studies reveal cellular mechanisms for interactive social behavior in animals and humans and highlight the prospective use of naturalistic approaches in social neuroscience.
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    Chemical and Biological Physics Guest Seminar

    Date:
    22
    Sunday
    January
    2023
    Lecture / Seminar
    Time: 12:00
    Title: How crystals flow – plastic deformation of colloidal single crystals
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Dr Ilya Svetlizky
    Organizer: Department of Chemical and Biological Physics
    Contact: lucio.frydman@weizmann.ac.il
    Abstract: Plastic (irreversible) deformation of crystals requires disrupting the crystalli ... Read more Plastic (irreversible) deformation of crystals requires disrupting the crystalline order, which happens through nucleation and motion of topological line defects called dislocations. Interactions between dislocations lead to the formation of complex networks that, in turn, dictate the mechanical response of the crystal. The severe difficulty in atomic systems to simultaneously resolve the emerging macroscopic deformation and the evolution of these networks impedes our understanding of crystal plasticity. To circumvent this difficulty, we explore crystal plasticity by using colloidal crystals; the micrometer size of the particles allows us to visualize the deformation process in real-time and on the single particle level. In this talk, I will focus on two classical problems: instability of epitaxial growth and strain hardening of single crystals. In direct analogy to epitaxially grown atomic thin films, we show that colloidal crystals grown on mismatched templates to a critical thickness relax the imposed strain by nucleation of dislocations. Our experiments reveal how interactions between dislocations lead to an unexpectedly sharp relaxation process. I will then show that colloidal crystals can be strain-hardened by plastic shear; the yield strength increases with the dislocation density in excellent accord with the classical Taylor equation, originally developed for atomic crystals. Our experiments reveal the underlying mechanism for Taylor hardening and the conditions under which this mechanism fails.
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    Rapid learning (and unlearning) in the human brain

    Date:
    19
    Thursday
    January
    2023
    Lecture / Seminar
    Time: 14:00-15:00
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Nitzan Censor
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Dr. Michal Ramot michal.ramot@weizmann.ac.il For accessibility issues c ... Read more Host: Dr. Michal Ramot michal.ramot@weizmann.ac.il For accessibility issues contact:naomi.moses@weizmann.ac.il
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    Abstract: A plethora of studies have pointed to sensory plasticity in the adult visual sys ... Read more A plethora of studies have pointed to sensory plasticity in the adult visual system, documenting long-term improvements in perception. Such perceptual learning is enabled by repeated practice, inducing use-dependent plasticity in early visual areas and their readouts. I will discuss results from our lab challenging the fundamental assumption in low-level perceptual learning that only 'practice makes perfect', indicating that brief reactivations of visual memories induce efficient rapid perceptual learning. Utilizing behavioral psychophysics, brain stimulation and neuroimaging, we aim to reveal the neurobehavioral mechanisms by which brief exposure to learned information modulates brain plasticity and supports rapid learning processes. In parallel, we investigate how these learning mechanisms operate across domains, for example by testing the hypothesis that similar inherent mechanisms may also result in maladaptive consequences, when brief reactivations occur spontaneously as intrusive enhanced memories following negative events. Unraveling the mechanisms of this new form of rapid learning could set the foundations to enhance learning in daily life when beneficial, and to downregulate maladaptive consequences of negative memories.
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    Brain-body interactions: sensations and predictions in the insular cortex

    Date:
    15
    Sunday
    January
    2023
    Lecture / Seminar
    Time: 15:00-16:00
    Location: Arthur and Rochelle Belfer Building for Biomedical Research
    Lecturer: Dr. Yoav Livneh
    Organizer: Life Sciences
    Contact: yael.kuperman@weizmann.ac.il

    Physics Colloquium

    Date:
    12
    Thursday
    January
    2023
    Colloquium
    Time: 11:15-12:30
    Title: How crystals flow - plastic deformation of colloidal single crystals
    Location: Edna and K.B. Weissman Building of Physical Sciences
    Lecturer: Ilya Svetlizky
    Organizer: Faculty of Physics
    Contact: eti.shalem@weizmann.ac.il
    Abstract: Plastic (irreversible) deformation of crystals requires disrupting the crystalli ... Read more Plastic (irreversible) deformation of crystals requires disrupting the crystalline order, which happens through nucleation and motion of topological line defects called dislocations. Interactions between dislocations lead to the formation of complex networks that, in turn, dictate the mechanical response of the crystal. The severe difficulty in atomic systems to simultaneously resolve the emerging macroscopic deformation and the evolution of these networks impedes our understanding of crystal plasticity. To circumvent this difficulty, we explore crystal plasticity by using colloidal crystals; the micrometer size of the particles allows us to visualize the deformation process in real-time and on the single particle level. In this talk, I will focus on two classical problems: instability of epitaxial growth and strain hardening of single crystals. In direct analogy to epitaxially grown atomic thin films, we show that colloidal crystals grown on mismatched templates to a critical thickness relax the imposed strain by nucleation of dislocations. Our experiments reveal how interactions between dislocations lead to an unexpectedly sharp relaxation process. I will then show that colloidal crystals can be strain-hardened by plastic shear; the yield strength increases with the dislocation density in excellent accord with the classical Taylor equation, originally developed for atomic crystals. Our experiments reveal the underlying mechanism for Taylor hardening and the conditions under which this mechanism fails.
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    “Functional MRI Advances at the Nexus of Acquisition, Processing, and Neuroscience”

    Date:
    12
    Thursday
    January
    2023
    Lecture / Seminar
    Time: 09:30-10:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Peter Bandettini
    Organizer: Clore Institute for High-Field Magnetic Resonance Imaging and Spectroscopy
    Contact: ana.naamat@weizmann.ac.il
    Abstract: MRI is truly unique in that contrast and acquisition can be manipulated to highl ... Read more MRI is truly unique in that contrast and acquisition can be manipulated to highlight a many tissues and physiologic processes at a wide range of speeds and resolutions. In the early 90’s, echo-planar imaging (EPI), a rapid imaging method that required specialized hardware, enabled time series acquisition of images - each collected in tens of milliseconds. Susceptibility contrast weighting sensitized the images to subtle shifts in blood oxygenation, allowing localized brain activation changes in oxygenation to be observed in near real time, thus introducing fMRI to the world. Since this breakthrough, fMRI has continued to advance in sophistication and impact. Higher fields, higher performance gradients, and novel pulse sequences and contrasts have allowed ever more subtle effects to be observed at higher fidelity, speed, and resolution. The signal became more informative as brain activation paradigms and processing methods advanced in conjunction with our deeper understanding of artifact and signal. Importantly, our insight into brain structure and function motivated and informed the experiments and, likewise, was enriched by the results. In this talk, I’ll trace the progress in fMRI, showing how the creative tension between advances in technology, processing, and our understanding of brain activation dynamics and physiology generated many of the innovations. My talk will include retinotopy, event-related fMRI, multi-echo EPI, resting state fMRI, connectivity, representational similarity analysis, decoding, naturalistic stimuli, inter-subject correlation, high field, and layer fMRI. Lastly, I’ll describe some of the technical and practical challenges facing the field today.
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    Capturing Neuronal Activity with more Precision and Fidelity in Time and Space

    Date:
    10
    Tuesday
    January
    2023
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Dr. Peter Bandettini
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host - Dr. Michal Ramot michal.ramot@weizmann.ac.il
    Abstract: My lab’s focus in recent years has been split between development of ultra-hig ... Read more My lab’s focus in recent years has been split between development of ultra-high resolution fMRI at high field and the exploration of more sensitive yet robust methods to find all the salient transients and trends in the signal. High field, high resolution fMRI relies heavily on the acquisition technology and the functional contrast used as well as unique processing approaches that segment, as well as possible, cortical layers for analysis. Our fMRI time series analysis research relies on creative paradigm design in conjunction with tailored processing methods that strike a balance between casting a wide net for potentially informative signals and applying just enough modeling to make sense of the data. Our goal is to use fMRI to see neuronal activity and capture neural correlates of behavior that have previously been elusive to more standard approaches.  Specifically, for our high resolution fMRI work, I will describe experiments demonstrating layer-specific activity in motor, somatosensory, and visual cortex that changes with tasks that modulate the hypothesized input and output cortical communication. In our lab, we perform layer fMRI using a functional contrast called VASO (vascular space occupancy) that is sensitive to blood volume changes in micro vessels - having more specificity than BOLD with only a small tradeoff in sensitivity. Layer fMRI has the potential to provide cortical hierarchy information and communication directionality based on the understanding that feedforward connections terminate predominantly in middle layers and feedback connections terminate in predominantly upper and lower layers. Hence by determining activation location across cortical depth, one can infer whether the activation is feedforward or feedback. I will also demonstrate how the use of resting state connectivity in conjunction with layer fMRI is able to discern such cortical hierarchy in visual areas. Lastly, I will also show examples of applications of layer fMRI in frontal cortex during a working memory task. In addition, I will show our high resolution fMRI work that has allowed us to discern a new digit organizational pattern in motor cortex.  For our time series work, I will show our recent results in using connectivity-based decoding for identifying, in an unsupervised manner, tasks being performed. In addition, I will show an application of naturalistic stimuli and inter subject correlation to characterize personality trait and language skills of individuals. Lastly, changes arousal state during scanning has been viewed as both a confound and opportunity. I demonstrate our effort to further characterize the temporal and spatial signatures of arousal state changes in fMRI time series.
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    Graphullerene: a new form of two-dimensional carbon

    Date:
    02
    Monday
    January
    2023
    Lecture / Seminar
    Time: 11:00-12:00
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Dr. Elena Meirzadeh
    Organizer: Department of Molecular Chemistry and Materials Science
    Contact: ana.naamat@weizmann.ac.il
    Abstract: The two natural allotropes of carbon, diamond and graphite, are extended network ... Read more The two natural allotropes of carbon, diamond and graphite, are extended networks of sp3- and sp2- hybridized carbon atoms, respectively. By mixing different hybridizations and geometries of carbon, one could conceptually construct countless synthetic allotropes. In this talk, I will introduce graphullerene, a new two-dimensional superatomic allotrope of carbon combining three- and four-coordinate carbon atoms. The constituent subunits of graphullerene are C60 fullerenes that are covalently interconnected within a molecular layer, forming graphene-like hexagonal sheets. The most remarkable thing about the synthesis of graphullerene is that the solid-state reaction produces large polyhedral crystals (hundreds of micrometers in lateral dimensions), rather than an amorphous or microcrystalline powder as one would typically expect from polymerization chemistry. Similar to graphite, the crystals can be mechanically exfoliated to produce molecularly thin flakes with clean interfaces—a critical requirement for the creation of heterostructures and optoelectronic devices. We find that polymerizing the fullerenes leads to a large change in the electronic structure of C60 and the vibrational scattering mechanisms affecting thermal transport. Furthermore, imaging few-layer graphullerene flakes using transmission electron microscopy and near-field nano-photoluminescence spectroscopy reveals the existence of moiré-like superlattices. The discovery of a superatomic cousin of graphene demonstrates that there is an entire family of higher and lower dimensional forms of carbon that may be chemically prepared from molecular precursors.
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    ATFS-1 coordinates mitochondrial network expansion and peroxisome biogenesis in the model organism Caenorhabditis elegans

    Date:
    27
    Tuesday
    December
    2022
    Lecture / Seminar
    Time: 10:00-11:00
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Dr. Tomer Shpika
    Organizer: Department of Biomolecular Sciences
    Contact: levana.ayvazo@weizmann.ac.il
    Abstract: As organisms develop, individual cells generate mitochondria and peroxisomes to ... Read more As organisms develop, individual cells generate mitochondria and peroxisomes to fulfill their physiological requirements. A decline, or dysfunction in these organelles is associated with ageing and a vast array of clinical manifestations including metabolic disorders and neurodegenerative diseases. Despite this, it is unknown how mitochondrial network expansion and peroxisome biogenesis is scaled to cell growth, and how cells maintain the organelles’ function during stress. The mitochondrial unfolded protein response (UPRmt) is a protective signaling pathway mediated by the transcription factor ATFS-1. Using genetic and biochemical approaches in the model organism Caenorhabditis elegans we demonstrate that ATFS-1 mediates an adaptable mitochondrial network expansion program and a peroxisomal retrograde response that is active throughout normal development. These findings as well as the therapeutic potential and future directions of my studies will be presented.
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    From atomic imaging and functionalizing of inorganic 2D materials to molecular imaging of organic 2D materials

    Date:
    18
    Sunday
    December
    2022
    Lecture / Seminar
    Time: 14:00-15:00
    Location: Perlman Chemical Sciences Building
    Lecturer: Prof. Ute Kaiser
    Organizer: Department of Molecular Chemistry and Materials Science
    Contact: ana.naamat@weizmann.ac.il
    Abstract: In this lecture, the theoretical and technical base for atomic imaging of defect ... Read more In this lecture, the theoretical and technical base for atomic imaging of defects in inorganic 2D materials in the low-voltage transmission electron microscope SALVE will be discussed. Atomic defects can significantly change the properties of the material: Using 2D-TMDs and 2D-TMPTs and corresponding heterostructures, this is shown experimentally and verified by corresponding quantum mechanical calculations. We also use the electron beam for the targeted formation of new phases in the inorganic 2D matrix. Since the interaction cross-sections of electron beam and organic 2D materials differ strongly from the inorganic case, we explore highest-resolution imaging conditions for 2D polymers and various 2D MOFs and show that there is a trend towards lower voltage TEM as well. We may conclude that low-voltage TEM and low-dimensional materials are just made for each other.
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    One possible reason why the petrous bone preserves ancient DNA relatively well is that it contains high concentrations of bone cells

    Date:
    15
    Thursday
    December
    2022
    Lecture / Seminar
    Time: 13:30
    Location: Room 590, Benoziyo Building for Biological Science, Weizmann Institute of Science
    Lecturer: Jamal Ibrahim
    Contact: harsh.raj@weizmann.ac.il
    Details: Join Zoom Meeting: https://weizmann.zoom.us/j/4845901524?pwd=dkYybWIvTXVSaW40Ym ... Read more Join Zoom Meeting: https://weizmann.zoom.us/j/4845901524?pwd=dkYybWIvTXVSaW40YmF2TEVxVFg0UT09 Meeting ID: 484 590 1524 Meeting password: 045940
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    Engineering Imaging Technologies and Discovering Biomarkers to Characterize Disease States

    Date:
    14
    Wednesday
    December
    2022
    Lecture / Seminar
    Time: 11:00-12:00
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Barbara S. Smith
    Organizer: Department of Molecular Chemistry and Materials Science
    Contact: natali.levin@weizmann.ac.il
    Details:
    Abstract: Neurodegenerative diseases are often clinically, genetically, and pathologically ... Read more Neurodegenerative diseases are often clinically, genetically, and pathologically heterogeneous. The clinical impact of understanding heterogeneity is perhaps best observed in cancer, where subtype-specificity within diagnoses, prognoses, and treatments have had a critical impact on clinical decision making and patient outcomes. A better understanding of how mechanisms are related to or drive heterogeneity within diseases such as Amyotrophic Lateral Sclerosis (ALS), will have a direct impact on patient outcomes, with a conscious effort to move towards precision medicine and targeted therapeutics for patients, which are urgently needed. For this reason, neuroscientists and oncologists have long aspired to achieve an understanding of the mechanisms governing pathophysiology. Our interdisciplinary work integrates technologies across a wide range of fields to surpass the current barriers in understanding disease pathophysiology. This talk will highlight a series of optical and photoacoustic imaging tools as well as multi-omics analysis that have been developed and studied in Dr. Smith’s lab to address the urgent need for non-invasive cancer detection and the characterization of neurological disorders. Through this work, we aim to develop translational technologies and methodologies to better characterize, understand, and detect disease pathogenesis, beyond current capabilities.
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    How movement regulates defensive behaviours in a social context

    Date:
    13
    Tuesday
    December
    2022
    Lecture / Seminar
    Time: 12:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Marta Moita
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Dr. Michal Ramot michal.ramot@weizmann.ac.il
    Abstract: Our work concerns the general problem of adaptive behavior in response to predat ... Read more Our work concerns the general problem of adaptive behavior in response to predatory threats, and of the neural mechanisms underlying a choice between strategies. Interacting predators and prey tightly regulate their motion, timing with precision when to hold, attack or escape. Motion cues are thus paramount in these interactions. Speed and (un)predictability have shaped the evolution of sensory and motor systems, the elucidation of which a great deal of research has been devoted. Much less attention has been paid to the role of motion as a social cue of threat or safety. We and others have found that prey animals use the movement of their neighbors to regulate their defensive responses. We have studied social regulation of freezing in rodents and found that rats use cessation of movement evoked sound, resulting from freezing, as a cue of danger. In addition, auto-conditioning, whereby rats learn the association between shock and their own freezing, during prior experience with shock, facilitates the use of freezing by others as an alarm cue. To further explore the social regulation of defensive responses we resorted to the use fruit flies as it easily allows testing of groups of varying sizes, the collection of large data sets and genetic access to individual neuronal types. We established that fruit flies in response to visual looming stimuli, simulating a large object on collision course, make rapid freeze/flee choices accompanied by lasting changes in the fly’s internal state, reflected in altered cardiac activity. Freezing in flies is also strongly modulated by the movement of surrounding neighbours. In contrast with rodents that use auditory cues, female flies use visual motion processed by visual projection neurons. Finally, I will discuss more preliminary findings suggesting that there are multiple states of freezing as measured by muscle activity in the fly legs. Having established the fly as a model to study freezing/fleeing decisions, we are in a great position to perform large scale integrative studies on the organization of defensive behaviours. Short Bio Marta Moita received her BSc degree in Biology at the University of Lisbon, in 1995. As part of Gulbenkian’s PhD programme in Biology and Medicine she developed her thesis work, on the encoding by place cells of threat conditioning under the supervision of Prof. Joseph Ledoux, at the New York University (1997-2002). In 2002, Marta Moita worked as a postdoctoral fellow in Dr. Tony Zador’s laboratory, at the Cold Spring Harbor Laboratory, to study the role of auditory cortex in sound discrimination. In 2004, she became a principal investigator, leading the Behavioral Neuroscience lab, at the Instituto Gulbenkian de Ciência. In 2008 her group joined the starting Champalimaud Neuroscience program. In 2018 and 2019 Marta Moita served as Deputy Director of Champalimaud Research. Her lab is primarily interested in understanding the mechanisms of behavior. To this end, the lab has focused on behaviors that are crucial for survival and present in a wide range of species, namely defensive behaviors triggered by external threats. Using a combination of state-of-the-art tools in Neuroscience (initially using rats and currently using fruit flies) and detailed quantitative descriptions of behavior, her lab aims to understand how contextual cues guide the selection between different defensive strategies and how the chosen defensive behavior and accompanying physiological responses are instantiated.    
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    Mapping protein conformations using EPR/DEER spectroscopy

    Date:
    12
    Monday
    December
    2022
    Colloquium
    Time: 11:00-12:15
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Stefan Stoll
    Organizer: Faculty of Chemistry
    Contact: sarah.amzallag@weizmann.ac.il
    Abstract: For many proteins, flexibility and motion form the basis of their function. In o ... Read more For many proteins, flexibility and motion form the basis of their function. In our lab, we quantify the conformational landscapes of proteins and their changes upon interaction with external effectors. Using Double Electron-Electron Resonance (DEER) spectroscopy, a form of Electron Paramagnetic Resonance (EPR) spectroscopy, we directly measure absolute distances and distance distributions between pairs of spin labels within proteins. From the data, we build quantitative structural and energetic models of the protein's intrinsic flexibility, conformational substates, and the structural changes induced by ligands and binding partners. In this talk, I present some of our recent results on the allosteric regulation of ion channels, the function of de novo designed protein switches, and novel methods for measuring protein conformations directly in their native cellular environment.
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    Mapping protein conformations using EPR/DEER spectroscopy Colloquium website

    Time Domain and High Frequency DNP Experiments

    Date:
    08
    Thursday
    December
    2022
    Lecture / Seminar
    Time: 09:30-10:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Robert G. Griffin
    Organizer: Clore Institute for High-Field Magnetic Resonance Imaging and Spectroscopy
    Contact: ana.naamat@weizmann.ac.il
    Abstract: Dynamic nuclear polarization (DNP) has become an invaluable tool to enhance sens ... Read more Dynamic nuclear polarization (DNP) has become an invaluable tool to enhance sensitivity of magic angle spinning (MAS) NMR, enabling the study of biomolecules and materials which are otherwise intractable. In this presentation we explore some new aspects of time domain DNP experiments and their applications. One of the main thrusts of DNP was to provide increased sensitivity for MAS spectroscopy of membrane and amyloid protein experiments. A problem frequently encountered in these experiments is the broadened resonances that occur at low temperatures when motion is quenched. In some cases it is clear that the proteins are homogeneously broadened, and therefore that higher Zeeman fields and faster spinning is required to recall the resolution. We show this is the case for MAS DNP spectra of Ab1-42 amyloid fibrils where the resolution at 100 K is identical to that at room temperature. Furthermore, we compare the sensitivity of DNP and 1H detected experiments and find that DNP, even with a modest ℇ=22, is ~x6.5 times more sensitive. We have also investigated the frequency swept-integrated solid effect (FS-ISE) and two recently discovered variants – the stretched solid effect (SSE) and the adiabatic solid effect (ASE). We find that the latter two experiments can give up to a factor of ~2 larger enhancement than the FS-ISE. The SSE and ASE experiments should function well at high fields. Finally, we discuss two new instrumental advances. First, a frequency swept microwave source that permits facile investigation of field profiles. It circumvents the need for a B0 sweep coil and the compromise of field homogeneity and loss of helium associated with such studies. This instrumentation has permitted us to elucidate the polarization transfer mechanism of the Overhauser effect, and also revealed interesting additional couplings (ripples) in field profiles of cross effect polarizing agents. Second, to improve the spinning frequency in DNP experiments, we have developed MAS rotors laser machined from single crystal diamonds. Diamond rotors should permit higher spinning frequencies, improved microwave penetration, and sample cooling.
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    The annual IsSDB symposium: Imaging development

    Date:
    08
    Thursday
    December
    2022
    Conference
    Time: 08:00
    Location: David Lopatie Conference Centre
    Contact: oren.schuldiner@weizmann.ac.il

    Atomic Resolution Structures of Amyloid Fibrils - Ab1-42 , Ab1-40 and b2-microglobulin

    Date:
    05
    Monday
    December
    2022
    Colloquium
    Time: 11:00-12:15
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Robert Guy Griffin
    Organizer: Faculty of Chemistry
    Contact: sarah.amzallag@weizmann.ac.il
    Abstract: Many peptides and proteins form amyloid fibrils whose detailed molecular structu ... Read more Many peptides and proteins form amyloid fibrils whose detailed molecular structure is of considerable functional and pathological importance. For example, amyloid is closely associated with the neurodegenerative diseases such as Alzheimer’s and Parkinson’s diseases. We review the macroscopic properties of fibrils and outline approaches to determining their microscopic structure using magic angle spinning (MAS) NMR with 2D and 3D dipole recoupling experiments involving spectral assignments and distance measurements. Key to obtaining high resolution is measurement of a sufficient number of NMR structural restraints (13C-13C and 13C-15N distances per residue). In addition, we demonstrate the applicability of 1H detection and dynamic nuclear polarization (DNP) to amyloid structural studies. We discuss the structures of three different amyloids: (1) fibrils formed by Ab1-42, the toxic species in Alzheimer’s, using >500 distance constraints; (2) fibrils of Ab1-40, a second form of Ab with a different structure, and (3) a structure of fibrils forned by b2-microglobulin, the 99 amino acid protein associated with dialysis related amylosis, using ~1200 constraints. Contrary to conventional wisdom, the spectral data indicate that the molecules in the fibril are microscopically well ordered. In addition, the structures provide insight into the mechanism of interaction of the monoclonal antibody, Aducanumab, directed against Ab amyloid.
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    Atomic Resolution Structures of Amyloid Fibrils - Ab1-42 , Ab1-40 and b2-microglobulin Colloquium website

    Large scale spatio-temporal organization of brain tumors: from oncostreams to liquid crystals

    Date:
    01
    Thursday
    December
    2022
    Lecture / Seminar
    Time: 14:00-15:00
    Location: Max and Lillian Candiotty Building
    Lecturer: Prof. Pedro Lowenstein
    Organizer: Dwek Institute for Cancer Therapy Research
    Contact: michal.av@weizmann.ac.il
    Details: https://weizmann.zoom.us/j/5065402023?pwd=a3Z6KzRCU0xJaUFoM2Y5emZwZm1oZz09

    Deciphering non-neuronal cells contribution to Alzheimer’s disease pathology using high throughput transcriptomic and proteomic methods

    Date:
    30
    Wednesday
    November
    2022
    Lecture / Seminar
    Time: 14:00-15:00
    Lecturer: Sedi Medina (PhD Thesis Defense Seminar) on Zoom
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Student Seminar - PhD Thesis Defense Zoom link:https://weizmann.zoom.us/j/910 ... Read more Student Seminar - PhD Thesis Defense Zoom link:https://weizmann.zoom.us/j/91099678492?pwd=RWp2dlNKYTc4NllCb3VLTGVGOVQ4UT09 Meeting ID: 910 9967 8492 Password: 837997
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    Abstract: Alzheimer's disease (AD) is a devastating pathology of the central nervous syste ... Read more Alzheimer's disease (AD) is a devastating pathology of the central nervous system (CNS) of unknown etiology which represents the most common neurodegenerative disorder. For decades, AD was perceived as a disease of the neuron alone. However, research advances in recent years have challenged this concept and shed light on the critical roles of non-neuronal cells on the development and progression of AD. In my PhD, I focused on understanding how two non-neuronal cell types - the Astrocytes and Microglia - respond to AD and how they possibly affect pathological processes. Our research identified a unique population of Astrocytes that significantly increased in association with brain pathology, which we termed disease-associated astrocytes (DAAs). This novel population of DAAs appeared at an early disease stage, increased in abundance with disease progression, and was not observed in young or in healthy adult animals. In addition, similar astrocytes appeared in aged wild-type (WT) mice and in aging human brains, suggesting their linkage to genetic and age-related factors. Aging is considered the greatest risk factor for AD, although the mechanism underlying the aging-related susceptibility to AD is unknown. One emerging factor that is involved in biological aging is the accumulation of senescent cells. Cellular senescence is a process in which aging cells change their characteristic phenotype. Under physiological conditions senescent cells can be removed by the immune system, however with aging, senescent cells accumulate in tissues, either due to a failure of effective removal or due to the accelerated formation of senescent cells. Our data highlight the contribution of non neuronal cells to AD pathogenesis by demonstrating  that 1. Overexpression of a specific gene by astrocytes affected the microglia cells' state, leading to a more homeostatic and less reactive microglial phenotype in comparison to the control group. 2. Accumulation of senescent microglia cells was observed in the brain of aged WT mice and AD mouse model (5xFAD), and by applying different therapeutic strategies we managed to observe significant quantitative differences in these cells, followed by a cognitive amelioration.
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    M.Sc thesis defense: "Self-Integrating Memories Based on Guided Nanowires"

    Date:
    24
    Thursday
    November
    2022
    Lecture / Seminar
    Time: 11:00-12:00
    Location: Helen and Milton A. Kimmelman Building
    Lecturer: Omri Ron
    Organizer: Department of Molecular Chemistry and Materials Science
    Contact: ana.naamat@weizmann.ac.il
    Abstract: Neuromorphic computing designs have an important role in the modern ‘big data ... Read more Neuromorphic computing designs have an important role in the modern ‘big data’ era, as they are suitable for processing large amount of information in short time, eliminating the von Neumann (VN) bottleneck. The neuromorphic hardware, taking its inspiration from the human brain, is designed to be used for artificial intelligence tasks via physical neural networks, such as speech or image recognition, bioinformatics, visual art processing and much more. The memristor (memory + resistor), is one of the promising building blocks for this hardware, as it mimics the behavior of a human synapse, and can be used as an analog non-volatile memory. The memristor has been proven as a viable memory element and has been used for constructing resistive random access memory (RRAM) as a replacement for current VN hardware. However, the mechanism of operation and the conducting bridge formation mechanisms in electrochemical metallization memristors still require further investigation. A planar single-nanowire (NW) based memristor is a good solution for elucidating the mechanism of operation, thanks to the high localization of switching events, allowing in-situ investigation as well as post-process analysis. Our group, which has developed the guided-growth approach to grow guided planar NWs on different substrates, has used this method to integrate guided epitaxial NWs into functional devices such as field-effect transistors (FETs), photodetectors and even address decoders. However, the guided-growth approach has not been used for creating memristors up to date. In this work, I successfully synthesized guided NWs of two metal-oxides on flat and faceted sapphire substrates – ZnO and β-Ga2O3 were successfully grown in the VLS mechanism as surface guided NWs. I successfully grew planar guided β-Ga2O3 NWs on six different sapphire substrates, for the first time as far as we know. We characterized the newly grown β-Ga2O3 NWs with SEM, TEM, EDS and Raman spectroscopy. The monoclinic NWs grew along surprising directions on the flat sapphire surfaces and I demonstrated a new mode of growth – epitaxy favored growth on a faceted surface, when graphoepitaxy is also possible. I created electrochemical metallization memristors with the obtained NWs and successfully demonstrated the effect of resistive switching for β-Ga2O3 guided NW based devices. With the abovementioned achievements, we expanded the guided-growth approach on flat and faceted sapphire surfaces, and opened the opportunity for creating surface guided-NW based neuromorphic hardware.
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    Molecular maps for odor processing in the mouse olfactory system

    Date:
    22
    Tuesday
    November
    2022
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Alexander Fleischmann
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host-Dr. Michal Ramot michal.ramot.weizmann.ac.il
    Abstract: We are interested in the organization and function of neural circuits for sensor ... Read more We are interested in the organization and function of neural circuits for sensory processing and behavior. A main goal of the lab is to integrate complementary approaches of system interrogation: we study the molecular diversity of cell types, their connectivity and functional properties; we investigate network dynamics and core computational principles; and we explore how learning and experience shapes behavioral decisions. I will discuss ongoing work aimed at characterizing molecular maps for odor processing in the mouse olfactory bulb. I will present preliminary data using spatial transcriptomics to generate a comprehensive map of glomerular identity and domain structure of the olfactory bulb. Furthermore, I will discuss single cell sequencing experiments and gene regulatory network models that define the diversity and connectivity of olfactory bulb projection neurons. I will try to illustrate how the early olfactory system of mice provides an ideal model system to integrate molecular biology, functional imaging, and behavioral experiments to address fundamental questions in sensory processing and behavior.
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    iSCAR seminar

    Date:
    10
    Thursday
    November
    2022
    Lecture / Seminar
    Time: 09:00-10:00
    Title: "Genome Stability in Reproduction and Aging: new insights from C. elegans"
    Location: Max and Lillian Candiotty Building
    Lecturer: Prof. Bjorn Schumacher
    Organizer: Department of Immunology and Regenerative Biology
    Contact: karina.yaniv@weizmann.ac.il

    Kinetic Asymmetry, the Neglected Ingredient in Chemical Coupling

    Date:
    07
    Monday
    November
    2022
    Colloquium
    Time: 11:00-12:15
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. R. Dean Astumian
    Organizer: Faculty of Chemistry
    Contact: sarah.amzallag@weizmann.ac.il
    Abstract: Chemical coupling plays the essential role in metabolism of providing a mechanis ... Read more Chemical coupling plays the essential role in metabolism of providing a mechanism by which energy released in an exergonic chemical reaction (often ATP hydrolysis) can be used to drive a different reaction energetically uphill. Through evolution coupling has come to be used also to drive the creation of concentration gradients across membranes via membrane molecular pumps such as the Na+K+ ATPase, and to harness chemical energy to perform mechanical work via proteins known as molecular motors, the most paradigmatic of which is muscle, i.e. myosin moving along actin. Recent work on synthetic molecular machines has reinvigorated efforts, both experimental and theoretical, to better understand chemical coupling. The key idea involves a mechanism known as a Brownian motor where energy is used, not to cause forward motion but to prevent backward motion. These ratchet mechanisms, named after “Feynman’s ratchet”, and mathematically described by a non-equilibrium equality for a pumped chemical potential difference, have provided the intellectual basis for the design of synthetic molecular machines. Detailed investigations of these synthetic devices have provided several surprises regarding the mechanism by which external energy drives molecular machines, most especially highlighting the key role of kinetic asymmetry.
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    Kinetic Asymmetry, the Neglected Ingredient in Chemical Coupling Colloquium website

    "In search for speed and resolution in (functional) neuroimaging at 7T and up"

    Date:
    03
    Thursday
    November
    2022
    Lecture / Seminar
    Time: 09:30-10:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Benedikt A Poser
    Organizer: Clore Institute for High-Field Magnetic Resonance Imaging and Spectroscopy
    Contact: ana.naamat@weizmann.ac.il
    Abstract: 7T MRI has proven itself as a great tool for neuroscientific investigation and h ... Read more 7T MRI has proven itself as a great tool for neuroscientific investigation and has been embraced by many researchers for both structural and functional neuroimaging. This talk will focus on acquisition for functional MRI at UHF. Gradient-echo BOLD fMRI is a long- and well-established tool for mapping brain activation in general neuroscience applications, owing to its robustness, acquisition speed and high sensitivity. With the signal change being driven by local deoxyhemoglobin content as a composite effect of the blood flow (CBF), blood volume (CBV) and oxygen uptake (CMRO2) response to neuronal activation, there is an overall weighting towards the draining vasculature as we go up in field strength. The super-linear sensitivity gains with B0 thus come at the expense of specificity, and this makes alternative measures such CBV or CBF more attractive, especially when aiming to resolve activation to laminar or columnar details with submillimetre resolutions. Making these techniques routinely useful, however, poses new acquisition-methodological challenges. In this talk I will discuss some of the advances in non-BOLD and non-echo-planar fMRI acquisition, with some focus on lifting the coverage limitations of VASO fMRI and CBF/ASL with parallel imaging, as well as non-Cartesian approaches to CBV and CBF measurement. Finally, I will touch on the topic of parallel RF transmission which undoubtedly play a role in future methodology and once more operator- and researcher-friendly implementations are available
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    Selective vascular injury induces degeneration of the olfactory bulb and development of alternatives for functional olfaction

    Date:
    26
    Wednesday
    October
    2022
    Lecture / Seminar
    Time: 11:15-12:15
    Location: Arthur and Rochelle Belfer Building for Biomedical Research
    Lecturer: Dr. Tamar Licht
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Prof. Noam Sobel
    Abstract: The olfactory bulb is the only recipient of direct olfactory sensory input in th ... Read more The olfactory bulb is the only recipient of direct olfactory sensory input in the brain and is therefore considered indispensable for odor detection. However, some humans demonstrate normal olfaction despite OB absence. The mechanisms involved in preserving olfaction and the pathogenesis leading to this condition are unknown. We use a mouse model mimicking vascular injury typical of the premature brain. We mapped maturation of blood vessels during development and found selective vulnerability of olfactory bulb vasculature during a specific developmental stage. This injury led to the development of adult, healthy mice with 5% - 35% of the original OB size. Mice could perform innate and learned olfactory tasks, and odor-specific sniff-locked responses were recorded from Piriform cortex. Anatomically, olfactory sensory neurons connect to the rudimentary OB and other ectopic regions and lose typical glomerular convergence. Accordingly, mitral/tufted apical dendrite extends beyond the territory of a single glomerulus. These and additional anatomical findings present alternative nose-to-brain connectivity may underlie preservation of olfaction in humans with degenerated olfactory bulbs.
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    Mapping internal representations with adaptive sampling, massive online experiments and cross-cultural research

    Date:
    24
    Monday
    October
    2022
    Lecture / Seminar
    Time: 11:00-12:00
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Dr. Nori Jacoby
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: ROOM 191 C-NEW
    Abstract: Our brain relies on internal representations to support perception, action, and ... Read more Our brain relies on internal representations to support perception, action, and decision-making. Internal representations are usually rich, multidimensional, and cannot be directly observed. How can these internal representations be characterized? How are they affected by experience? My work develops adaptive behavioral paradigms that integrate human decisions into computer algorithms via human-in-the-loop experiments. I combine these paradigms with a data-intensive expansion of the scale and scope of behavioral research by means of massive online experiments and cross-cultural comparative research. This talk presents “adaptive sampling,” a type of experimental paradigm inspired by Monte Carlo Markov Chain techniques. Each successive stimulus depends on a subject's response to the previous stimulus. This process allows us to sample from the complex and high-dimensional joint distribution associated with internal representations and obtain high-resolution maps of perceptual spaces. After introducing these methods and describing their implementation via large-scale online experiments and field experiments around the world, I demonstrate how they can be applied to fundamental questions in the understanding of the human mind. Specifically, I examine how biology and culture influence internal representations and how semantics influence perception.
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    Immunology and Regenerative Biology Colloquium

    Date:
    15
    Thursday
    September
    2022
    Lecture / Seminar
    Time: 11:00-12:00
    Title: Stem Cells: Coping with Stress
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Prof. Elaine Fuchs
    Organizer: Department of Immunology and Regenerative Biology
    Contact: lili.kasumov@weizmann.ac.il
    Abstract: Using mammalian skin as a model, Prof. Elaine Fuchs studies the remarkable prope ... Read more Using mammalian skin as a model, Prof. Elaine Fuchs studies the remarkable properties of tissue stem cells to replenish dying cells and repair wounds, and how the cells know which tasks to perform and when. She explores how stem cells sense and communicate with other cells in their environment. Aiming at advancing therapeutics, she dissects how communication networks malfunction in inflammation, aging, and cancers.
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    Valence Based Learning in Primate Amygdala Single-Neurons

    Date:
    04
    Sunday
    September
    2022
    Lecture / Seminar
    Time: 09:00-10:00
    Location: Arthur and Rochelle Belfer Building for Biomedical Research
    Lecturer: Tamar Reitich-Stolero (Advisor: Prof. Rony Paz Lab)
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Zoom link: https://weizmann.zoom.us/j/96622589021?pwd=Tkh1RWk0OFhaVFE0SW9KeU84Q1 ... Read more Zoom link: https://weizmann.zoom.us/j/96622589021?pwd=Tkh1RWk0OFhaVFE0SW9KeU84Q1cvZz09 Meeting ID: 966 2258 9021 Password: 022196
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    Abstract: Humans and animals tend to behave differently when learning from rewarding or av ... Read more Humans and animals tend to behave differently when learning from rewarding or aversive feedback, and the amygdala is hypothesized to play a role in these differences. Here, we studied neural mechanisms of learning and decision making in reward and punishment, namely post-stimulus rehearsal, balancing of exploration and exploitation and generalization. To study post-stimulus rehearsal in amygdala neurons, we investigated spike-sequences across simultaneously recorded neurons of non-human primates, while they learned to discriminate between aversive and pleasant tone-odor associations. We showed that valence specific sequences across amygdala neurons rehearsed the coding of the recent association, so they can serve as a coding mechanism that enhances memory formation by rehearsal of the recent association. Next, to examine neural coding of exploration under rewards and punishments, we recorded single neurons while human subjects were engaged in a probabilistic decision-making task with gain and loss conditions, and found more exploration when subjects tried to minimize their losses. We found two mechanisms of explorational choices: one is executed through firing rate of single neurons in the temporal cortex and amygdala and is shared across valence, and the other is executed by an increase in noise in amygdala neurons, and is specific to the loss condition. Finally, we found that over-generalization around a loss-conditioned tone was accompanied by a similar over response of amygdala neurons. Together, this work expands the knowledge of neural mechanisms that enhance learning and improves decision making, specifically in complex environments that include opportunities for rewards and risks for punishments. Zoom link: https://weizmann.zoom.us/j/96622589021?pwd=Tkh1RWk0OFhaVFE0SW9KeU84Q1cvZz09 Meeting ID: 966 2258 9021 Password: 022196
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    How brains add vectors

    Date:
    30
    Tuesday
    August
    2022
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Gaby Maimon
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Prof. Nachum Ulanovsky nachum.ulanovsky@weizmann.ac.il tel:6301 For ass ... Read more Host: Prof. Nachum Ulanovsky nachum.ulanovsky@weizmann.ac.il tel:6301 For assistance with accessibility issues contact: naomi.moses@weizmann.ac.il
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    Abstract: Many cognitive computations rely on the nervous system estimating mathematical v ... Read more Many cognitive computations rely on the nervous system estimating mathematical vectors, but aside from computer models, how brains represent vectors or perform vector operations remains unknown. In this talk, I will describe how the fly brain performs vector arithmetic in the context of spatial navigation. The central features of this vector calculator inside the insect brain may generalize to other nervous systems and other cognitive domains beyond navigation where vector operations are required.
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    Hybrid PhD Thesis Defense

    Date:
    08
    Monday
    August
    2022
    Lecture / Seminar
    Time: 11:00-13:00
    Title: Single-cell characterization and dynamics of senescent cells along aging
    Location: Wolfson Building for Biological Research
    Lecturer: Amit Agrawal (Valery Krizhanovsky Lab)
    Organizer: Department of Molecular Cell Biology
    Contact: michal.ovadia@weizmann.ac.il
    Details: You are invited to join via Zoom also: https://weizmann.zoom.us/j/96833441064?p ... Read more You are invited to join via Zoom also: https://weizmann.zoom.us/j/96833441064?pwd=cWJqbnZ3SVVWektWSHk4MTdUUXFBZz09 Meeting ID: 968 3344 1064 Password: 430692
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    Gallery: Hybrid PhD Thesis Defense Gallery
    Hybrid PhD Thesis Defense Lecture / Seminar website

    Emergent collective coding properties in hippocampal neuronal population activity

    Date:
    01
    Monday
    August
    2022
    Lecture / Seminar
    Time: 13:00-14:00
    Title: Student Seminar-PhD Thesis Defense HYBRID
    Location: Nella and Leon Benoziyo Building for Brain Research
    Lecturer: Liron Sheintuch
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Link:https://weizmann.zoom.us/j/97167587409?pwd=TDFFYWI0ZmF5YXk0TW5oN1ZKSStndz09 ... Read more Link:https://weizmann.zoom.us/j/97167587409?pwd=TDFFYWI0ZmF5YXk0TW5oN1ZKSStndz09 Meeting ID: 971 6758 7409 Password: 227875 Benoziyo Brain Research Building Room 113
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    Abstract: Populations of hippocampal neurons have been hypothesized to operate collectivel ... Read more Populations of hippocampal neurons have been hypothesized to operate collectively to support the stable maintenance of long-term memories. To test this hypothesis, we performed large-scale calcium imaging in the hippocampus of freely behaving mice that repeatedly explored the same environments over weeks. Surprisingly, we discovered that across separate visits to the same familiar environment, hippocampal neurons can collectively switch between multiple distinct spatial representations, without any apparent changes in sensory input or animal’s behavior. The distinct representations were spatially informative and stable over weeks, and switching between them required a complete disconnection of the animal from the environment, demonstrating the coexistence of distinct stable attractors in the hippocampal network. In the second part of the talk, I will present a comparison of the coding properties between hippocampal subfields CA1 and CA3 in novel environments. Place cells in CA3 had more precise and stable spatial tuning than place cells in CA1. Moreover, we showed that in CA3 the tuning of place cells exhibited a higher statistical dependence with their peers compared to in CA1, uncovering an organization of CA3 into cell assemblies. Interestingly, cells with stronger tuning peer-dependence had higher stability but not higher precision, suggesting that distinct mechanisms control these two aspects of the neural code. Overall, our results demonstrate that multiple attractor states can stably coexist in the hippocampus and suggest that a cell-assembly organization in hippocampal CA3 underlies the long-term maintenance of stable spatial codes. Link:https://weizmann.zoom.us/j/97167587409?pwd=TDFFYWI0ZmF5YXk0TW5oN1ZKSStndz09 Meeting ID: 971 6758 7409 Password: 227875
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    “Aspects of solar cell operation and reliability in High and low dimensions”

    Date:
    06
    Wednesday
    July
    2022
    Lecture / Seminar
    Time: 11:00-12:00
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Jean Francois Guillemoles
    Organizer: Department of Molecular Chemistry and Materials Science
    Contact: ana.naamat@weizmann.ac.il
    Abstract: The development of advanced photovoltaic devices, including those that might ove ... Read more The development of advanced photovoltaic devices, including those that might overcome the single junction efficiency limit, as well as the development of new materials, all rely on advanced characterization methods. Among all the existing methods optically based ones are very well adapted to quantitatively probe optoelectronic properties at any stage. We here present the use of multidimensional imaging techniques that record spatially, spectrally and time resolved luminescence images. We will discuss the benefits (and challenges) of looking into energy conversion systems from high dimensions perspective and those of dimensional reduction for improved intelligibility through some examples, mostly drawn from halide perovskite materials and device. These examples will help visit questions related to efficient transport and conversion in solar cells, as well as questions related to chemical and operational stability of the devices.
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    Swarm-Smart: Group motion and decision making in experiments and theory

    Date:
    06
    Wednesday
    July
    2022
    Conference
    Time: 08:00-16:30
    Location: David Lopatie Conference Centre
    Contact: nir.gov@weizmann.ac.il
    Swarm-Smart: Group motion and decision making in experiments and theory Conference website

    Using functional MRI to better understand neurodevelopmental disorders and to find biomarkers of treatment response in mental illness

    Date:
    05
    Tuesday
    July
    2022
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Keith Shafritz
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Dr. Michal Ramot michal.ramot@weizmann.ac.il tel:4417
    Abstract: Our ability to correctly diagnose and treat mental illness is limited by the ove ... Read more Our ability to correctly diagnose and treat mental illness is limited by the overlap in symptoms of many disorders, despite differing etiology. Determining the proper course of treatment is quite difficult because treating individual symptoms does not always lead to successful remission and typically involves a trial-and-error approach. Task-based functional MRI has become a highly useful tool for determining the brain regions involved in cognition and behavior in humans, with the potential to be used to find biomarkers of mental illness and treatment outcomes. Much of the research in this domain has focused on the differences in brain activation between groups of individuals with specific mental disorders and typically developing “control” groups. However, by relating brain activation patterns of clinical groups to symptom severity, developmental processes, and response to treatment at the individual level, we can determine brain-based markers that have the potential to be used as diagnostic tools in the future and to determine whether certain treatments would be helpful based on specific brain activation patterns. In this talk, I will present data from studies using task-based functional MRI in autism spectrum disorder, schizophrenia, and childhood adversity that illustrate the potential of this technology for diagnostic and treatment purposes. I will also discuss the promises and limitations of using fMRI as a clinical tool.
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    Advanced Concepts of Super-Resolution Fluorescence Microscopy

    Date:
    04
    Monday
    July
    2022
    Colloquium
    Time: 11:00-12:00
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Joerg Enderlein
    Organizer: Faculty of Chemistry
    Contact: sarah.amzallag@weizmann.ac.il
    Abstract: With the advent of super-resolution microscopy, the last ~25 years have seen a r ... Read more With the advent of super-resolution microscopy, the last ~25 years have seen a revolution in optical microscopy, pushing the spatial resolution capabilities of optical microscopy towards length scales that were typically accessible only by electron microscopy. In my presentation, I will give a short overview of the different principal approaches to super-resolution microscopy. I will briefly discuss the concepts of Structured Illumination Microscopy (SIM), Stimulated Emission Depletion (STED) microscopy, and Single Molecule Localization Microscopy (SMLM). Then, I will focus on two specific techniques where our group has contributed most. The first is Image Scanning Microscopy or ISM [1-3]. This technique uses a simple combination of confocal microscopy with wide-field image detection for doubling the resolution of conventional microscopy. I will explain the physical principals behind ISM, and the various kinds of its implementation. Meanwhile, ISM has found broad and wide applications and lies behind state-of-the-art commercial systems such as the extremely successful AiryScan microscope from Carl Zeiss Jena. The second method is Super-resolution Optical Fluctuation Imaging (SOFI), which uses the stochastic blinking of emitters for overcoming the classical diffraction limit of resolution, similar to single-molecule localization microscopy, but with much relaxed demands on blinking behavior and label density [4]. The third method is Metal-Induced Energy Transfer imaging or MIET imaging [5-6]. It addresses the axial resolution in microscopy, which is particularly important for resolving three-dimensional structures. MIET is based on the intricate electrodynamic interaction of fluorescent emitters with metallic nanostructures. I will present the basic principles and several applications of this technique.
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    Special Guest Seminar with Dr. Roy Maimon

    Date:
    30
    Thursday
    June
    2022
    Lecture / Seminar
    Time: 15:00-16:00
    Title: Tracing Glia-into-Neuron Conversion in the Aged Mouse Brain using Single Cell Spatial Transcriptomics
    Location: https://weizmann.zoom.us/j/95250374032?pwd=U0h4QmFQZENIZ0cvOENMZ0hMamdpQT09
    Lecturer: Dr. Roy Maimon
    Organizer: Department of Molecular Neuroscience
    Contact: bosmat.kariti@weizmann.ac.il

    Physics Hybrid Colloquium

    Date:
    30
    Thursday
    June
    2022
    Colloquium
    Time: 11:15-12:30
    Title: The construction of the Vera Rubin Observatory and cosmological measurements of dark matter and dark energy with LSST
    Location: Edna and K.B. Weissman Building of Physical Sciences
    Lecturer: Zeljko Ivesic
    Organizer: Faculty of Physics
    Contact: tamar.fuchs@weizmann.ac.il
    Details: 11:00 - Coffee, tea and more...
    Abstract: The Legacy Survey of Space and Time (LSST), the first project to be undertaken ... Read more The Legacy Survey of Space and Time (LSST), the first project to be undertaken at the new Vera Rubin Observatory, will be the most comprehensive optical astronomical survey ever undertaken. Starting in 2024, Rubin Observatory will obtain panoramic images covering the sky visible from its location in Chile every clear night for ten years. The resulting hundreds of petabytes of imaging data, essentially a digital color movie of the night sky, will include about 40 billion stars and galaxies, and will be used for investigations ranging from cataloging dangerous near-Earth asteroids to fundamental physics such as characterization of dark matter and dark energy. I will start my presentation with an overview of LSST science drivers and system design, and continue with a construction status report for the Vera Rubin Observatory. I will conclude with a brief discussion of a few Big Data challenges that need to be addressed before LSST data can be used for precise cosmological measurements.
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    What you always wanted to know about nanoparticles, proteins and biomaterials, but never dared to ask

    Date:
    30
    Thursday
    June
    2022
    Lecture / Seminar
    Time: 11:00-12:00
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Dr. Klaus D. Jandt
    Organizer: Department of Molecular Chemistry and Materials Science
    Contact: ana.naamat@weizmann.ac.il
    Abstract: This lecture presents an overview on major research work of the Fellow’s group ... Read more This lecture presents an overview on major research work of the Fellow’s group in the areas of polymer nanoparticles for drug delivery, control of protein adsorption on materials surfaces and protein nanofibers. In addition, the new excellence graduate school (Research Training Group) RTG 2723: Materials‐Microbe‐Microenvironments: Antimicrobial biomaterials with tailored structures and properties (M‐M‐M) funded by the German Science Foundation will be introduced. Polymer nanoparticles (PNP) became recently exceedingly popular through novel vaccination technologies but have also major potential for fighting inflammation and cancer. These drug release properties of the PNP depend on their structure. Yet, the literature reports little about the structure and the properties of most PNPs, except the chemical composition. The PNP’s crystallinity, thermal and mechanical properties are frequently ignored, even though they may play a key role in the drug delivery properties of the PNPs. Protein adsorption on biomaterials is the first process after implantation and determines much of the fate of the biomaterial, such as cell adhesion, blood coagulation or infection at the implant site. Despite decades of research, only rules of thumb exist to predict protein adsorption behavior. We present nanotechnological approaches to control protein adsorption using nanostructured semicrystalline polymers and crystal facets of TiO2. Selfassembled protein nanofibers consisting of one or more proteins, potentially allow to tailor the properties of biomaterials interfaces and to create bone mimetic structures. Finally, the new DFG‐RTG 2723: Materials‐Microbe‐Microenvironments: Antimicrobial biomaterials with tailored structures and properties (M‐M‐M) in Jena will be introduced. The aim of the RTG is to provide excellent training for approximately 40 international doctoral researchers in antimicrobial biomaterials in interdisciplinary tandem projects, connecting materials science and medical science. The RTG pursues a new strategy by developing antibiotic free biomaterials, where the antimicrobial action is based mainly on physical principles. The new RTG offers ample opportunity for fruitful cooperation and exchange with leading research institutions in Israel.
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    Molecular design of solid catalysts

    Date:
    29
    Wednesday
    June
    2022
    Lecture / Seminar
    Time: 11:00-12:00
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Alexander Katz
    Organizer: Department of Molecular Chemistry and Materials Science
    Contact: natali.levin@weizmann.ac.il
    Abstract: This colloquium will be divided into two applications parts, dealing with synthe ... Read more This colloquium will be divided into two applications parts, dealing with synthesis of supported molecular catalysts and solid catalysts for photoprotection. In the first of these areas, we describe a mechanical approach for stabilizing supported weakly interacting active sites (i.e. those that interact non-covalently with the support) against aggregation and coalescence. We use silica as a prototypical example of a support, and an iridium pair-site catalyst incorporating bridging calixarene ligands as an active site. Atomic-resolution imaging of the Ir centers before and after ethylene-hydrogenation catalysis show the metals resisted aggregation and deactivation, remaining atomically dispersed and accessible for catalysis. When active sites are located at unconfined environments, the rate constants for ethylene hydrogenation are markedly lower compared with confining external-surface pockets [1], in line with prior observations of similar effects in olefin epoxidation catalysis [2,3]. Altogether, these examples represent new opportunities for enhancing reactivity on surfaces by synthetically controlling mechanical features of active site catalyst environments. In the second of these areas, reactive oxygen species (ROS) are associated with several human health pathologies and are invoked in the degradation of natural ecosystems as well as building materials that are used in modern infrastructure (e.g., paints and coatings, polymers, etc). Natural antioxidants such as vitamin E function as stoichiometric reductants (i.e. reaction with ROS synthesizes rancid oils). While enzymes such as superoxide dismutase working in tandem with catalase decompose decompose ROS to H2O and O2 through H2O2 as an intermediate, these enzymes are fragile and costly. Other non-stoichiometric commercial antioxidants that degrade ROS include hindered amine light stabilizers (HALS). Here, we demonstrate that cerium carbonate acts as a degradation catalyst for photogenerated ROS, and describe the performance and characterization of this new catalyst using X-ray photoelectron spectroscopy, and in comparison with HALS and stoichiometric reductants. Our results demonstrate catalytic antioxidant activity of cerium carbonate when dispersed in polymethylmethacrylate polymer. FTIR data demonstrate that a dispersion of 2 wt. % cerium carbonate within the polymer essentially stops degradation by photogenerated ROS, which otherwise cause oxidation of the polymer backbone, in the control polymer lacking cerium carbonate. Experiments with methylene blue dye in aqueous solution demonstrate that cerium carbonate decreases the rate of ROS degradation of dye, in the presence of UV irradiation and air by 16 fold. These effects become even more pronounced (over 600 fold decrease in rate of ROS dye degradation) when cerium carbonate is paired with a photoactive metal oxide. The mechanism involved in this latter case crudely mimics the enzyme tandem sequence referred to above. [1] C. Schöttle, E. Guan, A. Okrut, N. A. Grosso-Giordano, A. Palermo, A. Solovyov, B. C. Gates, A. Katz*, Journal of the American Chemical Society, J. Am. Chem. Soc. 2019, 141, 4010-4015. [2] N. A. Grosso-Giordano, C. Schroeder, A. Okrut, A. Solovyov, C. Schottle, W. Chasse, N. Marinkoyic, H. Koller, S. I. Zones, A. Katz, Journal of the American Chemical Society 2018, 140, 4956-4960. [3] N. A. Grosso-Giordano, A. S. Hoffman, A. Boubnov, D. W. Small, S. R. Bare, S. I. Zones, A. Katz, Journal of the American Chemical Society 2019, 141, 7090-7106. [4] M. K. Mishra, J. Callejas, M. Pacholski, J. Ciston, A. Okrut, A. Van Dyk, D. Barton, J. C. Bohling, A. Katz, ACS Applied Nano Materials 2021, 4, 11, 11590-11600.
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    Special guest seminar with Dr. Or Shemesh

    Date:
    28
    Tuesday
    June
    2022
    Lecture / Seminar
    Time: 09:30-10:30
    Title: Infectious Neuroscience - Do Common Pathogens Play a Part in Neurodegeneration?
    Location: Arthur and Rochelle Belfer Building for Biomedical Research
    Lecturer: Dr. Or Shemesh
    Organizer: Department of Molecular Neuroscience
    Contact: Bosmat.kariti@weizmann.ac.il
    Abstract: Herpes Simplex Virus 1 (HSV-1) is a usual suspect when it comes to Alzheimer's d ... Read more Herpes Simplex Virus 1 (HSV-1) is a usual suspect when it comes to Alzheimer's disease (AD), and its DNA and RNA were found in the brains and serological samples of AD patients. Such molecular presence of HSV-1 in AD is especially intriguing as HSV-1 virions are rarely detected in AD brains. To follow the molecular footsteps detected, we imaged viral proteins in postmortem human AD brains at superior resolution using expansion microscopy, a tissue manipulation method that physically expands the samples by a factor of 4.5x, allowing a 40 nm imaging resolution, and immunolabeled herpetic proteins, AD pathologies and cell markers. We found an abundance of herpetic proteins, previously undetectable with standard methods, across large brain areas. Importantly, we found that HSV-1 proteins strongly co-localized with AD pathologies. Consequently, we hypothesized that expression of HSV-1 proteins during latency may be linked to AD pathology. We are now in the process of characterizing the HSV-1 proteome in AD brains by imaging key proteins in expanded AD brain slices and examining their colocalization with AD pathologies across brain areas and disease stages. As a complementary system to the fixed human brain slices, we are exposing live human brain organoids, to HSV-1, and imaging the relationships between viral proteins and the formation of AD pathologies via expansion microscopy. Pathogens may be triggers of immune responses driving AD; this study would shed light on one common pathogen, HSV-1, while serving as a framework to unveiling molecular causation between infectious agents and AD hallmarks.
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    Sugar: A gut choice

    Date:
    21
    Tuesday
    June
    2022
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Diego V. Bohórquez, Ph.D.
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Abstract: Animals distinguish sugars from non-nutritive sweeteners even in the absence of ... Read more Animals distinguish sugars from non-nutritive sweeteners even in the absence of sweet taste. This hidden sugar sense seems to reside in the gut, but the cells and neural circuits are unknown. In 2018, the Bohórquez Laboratory discovered a neural circuit linking the gut to the brain in one synapse. The neural circuit is formed between neuropod cells in the gut and the vagus nerve. This neural circuit is essential to convey sensory cues from sugars. In 2020, the Bohórquez Laboratory discovered using a new fiber optic technology along with optogenetics, that animals rely on neuropod cells to distinguish sugars from non-caloric sweeteners. Much like the brain relies on retinal cone cells to see color, gut neuropod cells help the brain’s choose sugar over non-caloric sweeteners.
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    Deciphering non-neuronal cells fate in Alzheimer’s disease by next generation transcriptomics

    Date:
    20
    Monday
    June
    2022
    Lecture / Seminar
    Time: 11:30-12:30
    Title: Student Seminar - PhD Thesis Defense -ZOOM-
    Lecturer: Mor Kenigsbuch
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Zoom link-https://weizmann.zoom.us/j/98815291638?pwd=cnZTanhzWkEyYmh4Mjk4OWxHMGE ... Read more Zoom link-https://weizmann.zoom.us/j/98815291638?pwd=cnZTanhzWkEyYmh4Mjk4OWxHMGE5UT09 Meeting ID:988 1529 1638 Password:880170
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    Abstract: For decades, Alzheimer's disease (AD) was perceived as a disease of the neuron a ... Read more For decades, Alzheimer's disease (AD) was perceived as a disease of the neuron alone. However, research advances in recent years have challenged this concept and shed light on the critical roles of other cells within the central nervous system (CNS) and the periphery. Within the CNS, microglia and astrocytes were revealed to be key players in disease progression, while other cell types, such as oligodendrocytes, pericytes, and endothelial cells, remained relatively understudied. In my PhD, I focused on understanding how two non-neuronal cell types, the oligodendroglia in the brain parenchyma and the choroid plexus (CP) epithelium, respond to AD and how they possibly affect pathological processes. My research identified a cellular state of oligodendrocytes that significantly increased in association with brain pathology, which we termed disease-associated oligodendrocytes (DOLs). Oligodendrocytes with DOL signature could also be identified in a mouse model of tauopathy and other neurodegenerative and autoimmune inflammatory conditions, suggesting a common response of oligodendrocytes to severe deviation from homeostasis. In the second part of my PhD, I contributed to a research aiming to investigate the mechanisms underlying the decline of the CP's neuroprotective abilities in the context of AD. We found that exposure of choroid plexus epithelial cultures to 24-hydroxycholesterol (24-OH), the enzymatic product of the brain-specific enzyme cholesterol 24-hydroxylase (CYP46A1), results in downregulation of aging- related transcriptomic signatures-such as Interferon type I (IFN-I) associated inflammation. Moreover, we found that CYP46A1 is constitutively expressed by the CP of humans and mice but is reduced in AD patients and 5xFAD mice. Overexpression of Cyp46a1 at the CP in 5xFAD mice attenuated cognitive loss and brain inflammation. Our results suggest that CP CYP46A1 is an unexpected safeguard against chronic anti-viral-like responses that can be rescued when lost. Overall, my PhD work highlights the significance of studying the fate of non-neuronal cell types in neurodegenerative diseases, in general, and in AD, in particular, and emphasizes the potential of next- generation transcriptomic techniques as a powerful tool to unveil previously unexpected pathways and mechanisms involved in these diseases.  Zoom link-https://weizmann.zoom.us/j/98815291638?pwd=cnZTanhzWkEyYmh4Mjk4OWxHMGE5UT09 Meeting ID:988 1529 1638 Password:880170
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    Nonoscillatory coding and multiscale representation of ultra-large environments in the bat hippocampus

    Date:
    09
    Thursday
    June
    2022
    Lecture / Seminar
    Time: 15:00-16:30
    Title: Student Seminar - PhD Thesis Defense
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Tamir Eliav
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Abstract: The hippocampus plays a key role in memory and navigation, and forms a cognitive ... Read more The hippocampus plays a key role in memory and navigation, and forms a cognitive map of the world: hippocampal ‘place cells’ encode the animal’s location by activating whenever the animal passes a particular region in the environment (the neuron’s ‘place field’). Over the last 50 years of hippocampal research, almost all studies have focused on rodents as animal models, using small laboratory experimental setups. In my research, I explored hippocampal representations in a naturalistic settings, in a unique animal model – the bat. My talk will outline two main stories: (i) In rodents, hippocampal activity exhibits ‘theta oscillations’. These oscillations were proposed to support multiple functions, including memory and sequence formation. However, absence of clear theta in bats and humans has questioned these proposals. Surprisingly, we found that in bats hippocampal neurons exhibited nonoscillatory phase-coding. This highlights the importance of phase-coding, but not oscillations per se, for hippocampal function across species – including humans. (ii) Real-world navigation requires spatial representation of very large environments. To investigate this, we wirelessly recorded from hippocampal dorsal CA1 neurons of bats flying in a long tunnel (200 meters). Place cells displayed a multifield multiscale code: Individual neurons exhibited multiple place fields of diverse sizes, ranging from 0.6 to 32 meters, and the fields of the same neuron differed up to 20-fold in size. Theoretical analysis showed that the multiscale code allows representing large environments with much better accuracy than other codes. Thus, by increasing the spatial scale, we uncovered a neural code that is radically different from classical spatial codes. Together, these results highlight the power of the comparative approach, and demonstrate that studying the brain under naturalistic settings and behavior enables discovering new unknown aspects of the neural code.
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    Molecular mechanisms underlying neural circuit assembly in the mammalian visual system

    Date:
    09
    Thursday
    June
    2022
    Lecture / Seminar
    Time: 12:30-13:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Alex L. Kolodkin
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Hosts- Dr. Meital Oren meital.oren@weizmann.ac.il Dr. Michal Rivlin michal.r ... Read more Hosts- Dr. Meital Oren meital.oren@weizmann.ac.il Dr. Michal Rivlin michal.rivlin@weizmann.ac.il For issues on accessibility matters: naomi.moses@weizmann.ac.il
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    Abstract: The assembly of neural circuits critical for visual system function includes the ... Read more The assembly of neural circuits critical for visual system function includes the differentiation of select subtypes of amacrine cells (ACs) and retinal ganglion cells (RGCs), the elaboration of precise connections within the retina among ACs and RGCs, and targeting of RGC axons to their appropriate retino-recipient regions within the CNS. I will consider these events in the context of the mammalian accessory optic system (AOS), which is tuned to detect slow directional motion in order to stabilize images on the retina. This work implicates mutations in certain human genes that encode orthologues of proteins critical for assembling murine AOS circuits in phylogenetically conserved aspects of visual system function.
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    Multiplexed imaging of endogenous molecular beacons with MRI

    Date:
    09
    Thursday
    June
    2022
    Lecture / Seminar
    Time: 09:30-10:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Moriel Vandsburger
    Organizer: Clore Institute for High-Field Magnetic Resonance Imaging and Spectroscopy
    Contact: ana.naamat@weizmann.ac.il
    Abstract: Novel treatments that are under development for heart failure, metabolic disorde ... Read more Novel treatments that are under development for heart failure, metabolic disorders, kidney disease, and other debilitating illnesses generally target specific molecular and cellular mechanisms of action. However, assessment of such treatments is often complicated by the lack of easily measurable blood biomarkers, and a reliance upon repeated tissue biopsy. Subsequently, many exploratory studies utilize non-invasive imaging methods to characterize changes in whole organ structure and function as surrogate markers for underlying cellular and molecular changes. Although such measurements can be performed serially, such macro-level imaging measurements are often insensitive to physiologically meaningful treatment responses. In addition, the lack of target specificity represents a fundamental barrier both in pre-clinical development and clinical trials where the information potentially gleaned from a more physiologically rich data set would be of high value to further therapeutic development. My primary research interest is in using magnetic resonance imaging (MRI) as a platform technology for non-invasive and multiplexed molecular imaging in heart and kidney failure. Using a first principles approach, my group seeks to unify changes in myocardial and kidney MRI physics properties with advanced pulse sequence design and analysis in order to enable integrative physiological imaging that both identifies mechanisms of failure earlier than existing diagnostics, and directly measures the impacts of new therapies on their intended therapeutic targets. Using a process of chemical exchange saturation transfer (CEST) we have designed pre-clinical methods to quantify viral carriers of somatic cell gene editing machinery, gene transfer following adeno associated viral gene therapy, and to longitudinally quantify cell survival/proliferation following intra-myocardial implantation in mouse models of regenerative cell therapy. In addition, cardiac CEST approaches for imaging of myocardial creatine and fibrosis using endogenous contrast mechanisms have been translated from mouse models to clinical application in obese adults and renal failure patients on routine hemodialysis. Most recently we have developed methods to probe renal physiology and failure based on endogenous CEST contrast generated by urea. When integrated, these approaches can enable serially non-invasive and multi-scale analysis from the level of gene expression up to whole organ function in disease settings that currently have limited non-invasive molecular tools.
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    Thalamic regulation of prefrontal dynamics for cognitive control

    Date:
    07
    Tuesday
    June
    2022
    Lecture / Seminar
    Time: 15:30-16:30
    Title: ZOOM
    Lecturer: Prof. Michael Halassa
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Zoom link- Zoom Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMU ... Read more Zoom link- Zoom Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421
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    Abstract: Interactions between the thalamus and cortex are critical for normal cognition. ... Read more Interactions between the thalamus and cortex are critical for normal cognition. Although classical theories emphasize its role in transmitting signals to or between cortical areas, recent studies show that the thalamus modulates cortical function through additional mechanisms. In this talk, I will discuss findings that highlight the role of the mediodorsal (MD) thalamus in regulating prefrontal excitatory/inhibitory balance and effective connectivity during decision making. I will present recently published data showing that the MD thalamus dynamically adjusts prefrontal evidence integration according to incoming stimulus statistics. I will also present unpublished data showing how the thalamus may be a nexus for handling distinct types of task uncertainty. Given that MD-PFC interactions are known to be perturbed in schizophrenia, these findings may be relevant to suboptimal management of uncertainty that leads to aberrant beliefs. If time allows, I will present early collaborative work in that domain. Zoom Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421
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    On discovery and sensitivity in (photo)catalysis

    Date:
    07
    Tuesday
    June
    2022
    Lecture / Seminar
    Time: 14:00-15:00
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Frank Glorius
    Organizer: Department of Molecular Chemistry and Materials Science
    Contact: natali.levin@weizmann.ac.il
    Abstract: Catalysis is a key technology, since it allows for increased levels of selectivi ... Read more Catalysis is a key technology, since it allows for increased levels of selectivity and efficacy of chemical transformations. While significant progress can be made by rational design or engineered step-by-step improvements, many pressing challenges in the field require the discovery of new and formerly unexpected results. Arguably, the question “How to discover?” is at the heart of the scientific process. In this talk, (smart) screening strategies for accelerated discovery and improved reproducibility will be presented, together with new photocatalytic transformations. In addition, two other exciting areas will be addressed: N-heterocyclic carbenes (NHCs) are powerful ligands in catalysis due to their strong electron-donating properties and their ability to form very stable bonds to transition metals. In addition, they can stabilize and modify nanoparticles or flat metals surfaces, outperforming established phosphine or thiol ligands regarding structural flexibility, electron-donating properties and stability. Current research is highly interdisciplinary and focusses on the basic understanding of the binding mode, mobility and the elucidation of the impact on the surface properties. Exciting applications in materials science, heterogeneous catalysts and beyond are within reach. Biological membranes and their constituents are some of the most important and fundamental building blocks of life. However, their exact role in many essential cellular processes as well as in the development of diseases such as cancer or Alzheimer's is still not very well understood. Thus, we design, synthesize and evaluate imidazolium-based lipid analogs that can integrate into biological membranes and can be used as probes for live cell imaging or to manipulate membranes.
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    Exploring redox switches in aging and stress

    Date:
    07
    Tuesday
    June
    2022
    Lecture / Seminar
    Time: 10:00-11:00
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Prof. Dana Reichmann
    Organizer: Department of Biomolecular Sciences
    Contact: levana.ayvazo@weizmann.ac.il
    Abstract: Cellular redox status affects diverse cellular functions, including proliferatio ... Read more Cellular redox status affects diverse cellular functions, including proliferation, protein homeostasis, and aging. Thus, individual differences in redox status can give rise to distinct sub-populations even among cells with identical genetic backgrounds. I will describe a new and robust methodology to quantify the redox-dependent heterogeneity on a single cell level and how we can use it to identify new redox-regulated proteins. One of such identified redox switch proteins is a key player in the protein degradation pathway, Cdc48 (VCP /p97). I will show how we can use structural mass spectrometry, computational modeling, and cell biology to define its working cycle.
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    Architecture and function of small neuronal networks

    Date:
    06
    Monday
    June
    2022
    Lecture / Seminar
    Time: 13:30-15:30
    Title: Student Seminar - PhD Thesis Defense HYBRID
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Adam Haber
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Hybrid seminar Schmidt Lecture hall Zoom Link: https://weizmann.zoom.us/j/95 ... Read more Hybrid seminar Schmidt Lecture hall Zoom Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421
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    Abstract: Neurons in the brain form complex networks of synaptic connections. These elabor ... Read more Neurons in the brain form complex networks of synaptic connections. These elaborate networks define the physical scaffold on which neural activity occurs, and shape the collective dynamics of groups of neurons. In this talk, I will present my work on understanding the structural design principles of neural networks, and the relations between their architecture and their functional properties. First, I will ask what are the structural features that shape the function of neural networks, and show we can learn these features from large ensembles of simulated networks. Second, I will discuss how a strong biological constraint on the structure of neural networks does not incur a computational cost, and may even be functionally beneficial. Third, I will show how we can build connectomes which capture both the structure and the function of real data, using a small number of simple biological features.   Zoom Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421
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    Fast multimodal imaging of brain dynamics underlying sleep and wakefulness

    Date:
    17
    Tuesday
    May
    2022
    Lecture / Seminar
    Time: 14:00-15:00
    Title: On ZOOM
    Lecturer: Dr. Laura Lewis
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: ZOOM Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeH ... Read more ZOOM Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421
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    Abstract: When we fall asleep, brain function and physiology are rapidly transformed. Unde ... Read more When we fall asleep, brain function and physiology are rapidly transformed. Understanding the neural basis of sleep requires imaging methods that can capture multiple aspects of brain physiology at fast timescales. We develop approaches for analyzing human brain physiology using multimodal neuroimaging, and apply them to investigate the neural origins and consequences of sleep. We found that accelerated methods for fMRI can enable imaging subsecond neural dynamics throughout the human brain. We applied these methods to investigate the neural dynamics that occur at state transitions, and identified temporal sequences within thalamocortical networks that precede the moment of awakening from sleep. In addition, we developed a method to image cerebrospinal fluid flow, and discovered large waves of fluid flow that appear in the sleeping human brain. Together, these studies highlight the new biological information that can be extracted from fast fMRI data, and use this approach to discover neurophysiological dynamics unique to the sleeping brain. Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421
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    Brain plasticity: Regulation and Modulation

    Date:
    16
    Monday
    May
    2022
    -
    17
    Tuesday
    May
    2022
    Conference
    Time: 08:00 - 18:00
    Location: David Lopatie Conference Centre
    Organizer: Department of Brain Sciences
    Contact: ilan.lampl@weizmann.ac.il

    Ambient Imaging of Biological Samples Using Nanospray Desorption Electrospray Ionization (nano-DESI) Mass Spectrometry

    Date:
    10
    Tuesday
    May
    2022
    Lecture / Seminar
    Time: 12:30
    Location: Arthur and Rochelle Belfer Building for Biomedical Research
    Lecturer: Prof. Julia Laskin
    Organizer: Department of Life Sciences Core Facilities
    Contact: Uwe.Heinig@weizmann.ac.il

    Representation of 3D space in the mammalian brain: From 3D grid cells in flying bats to 3D perception in flying humans

    Date:
    27
    Wednesday
    April
    2022
    Lecture / Seminar
    Time: 12:30-13:30
    Title: Student Seminar - PhD Thesis Defense FRONTAL
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Gily Ginosar
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Abstract: While our world is three-dimensional (3D), spatial perception is most often stud ... Read more While our world is three-dimensional (3D), spatial perception is most often studied in animals and humans navigating across 2D surfaces. I will present two cases in which the consideration of the 3D nature of the world has led us to surprising results. The first case regards the neural recording of mammalian grid cells. Grid cells that are recorded over 2D surfaces create a hexagonal-shaped repetitive lattice, which inspired many theoretical studies to investigate the pattern’s mechanism and function. Upon recording in bats flying through 3D space, we found that grid cells did not exhibit a hexagonal global lattice, but rather showed a local order – with grid-fields exhibiting fixed local distances. Our results in 3D strongly argue against most of the prevailing models of grid-cell function, and we suggest a unified model that explains the results in both 2D and 3D.  The second case regards the perception of 3D space in humans. Different behavioral studies have shown contradicting evidence of human perception of 3D space being either isotropic or vertically compressed. We addressed this question using human experts in 3D motion and navigation – fighter pilots – studied in a flight simulator. We considered two aspects of the perception of 3D space: surrounding space and travelled space. We show that different aspects of the perception of space are shaped differently with experience: whereas the perception of the 3D surrounding space was vertically compressed in both expert and non-expert subjects, fighter pilots exhibited isotropic perception of travelled space, whereas non-expert subjects retained a distorted perception.  Together, our research sheds light on the differences and similarities between the coding of 3D versus 2D space, in both animals and humans.  
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    "SARM1 Ring to Rule Them All"

    Date:
    26
    Tuesday
    April
    2022
    Lecture / Seminar
    Time: 10:00-11:00
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Prof. Yarden Opatowsky
    Organizer: Department of Biomolecular Sciences
    Contact: levana.ayvazo@weizmann.ac.il
    Abstract: SARM1 is a central executor of neurodegeneration. Remarkably, neurons from SA ... Read more SARM1 is a central executor of neurodegeneration. Remarkably, neurons from SARM1 knock-out mice (which appear to be normal in many respects) show prolonged resistance for neuronal degeneration after mechanical damage, oxidative stress, and chemotherapy treatments. Mechanistically, SARM1 contains NADase activity, which, in response to nerve injury, depletes the key cellular metabolite, NAD+. To gain structural knowledge of SARM1 we use X-ray crystallography of isolated SARM1 domains and single particle EM 3D reconstruction of the intact protein. We discovered that SARM1, like other apoptotic complexes, assembles into an oligomeric ring. Structure analysis and additional experiments in cultured cells points at a surprising molecular mechanism by which SARM1 is kept inactive during homeostasis and how it becomes activated in response to metabolic and oxidative stress conditions 1,2,3. 1 Sporny, M. et al. Structural Evidence for an Octameric Ring Arrangement of SARM1. J Mol Biol 431, 3591-3605, doi:10.1016/j.jmb.2019.06.030 (2019). 2 Sporny, M. et al. Structural basis for SARM1 inhibition and activation under energetic stress. Elife 9, doi:10.7554/eLife.62021 (2020). 3.Khazma T. et al. A Duplex Structure of SARM1 Octamers Induced by a New Inhibitor. bioRxiv doi.org/10.1101/2022.03.02.482641 (2022).
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    iSCAR Seminar

    Date:
    26
    Tuesday
    April
    2022
    Lecture / Seminar
    Time: 09:00
    Title: Blood and lymphatic vessels as organizers of organ growth and regeneration
    Location: Max and Lillian Candiotty Building
    Lecturer: Prof. Karina Yaniv
    Organizer: Life Sciences
    Contact: karina.yaniv@weizmann.ac.il

    Magnetic Resonance “Colors”: Design and Implementation in Materials and Life Sciences

    Date:
    25
    Monday
    April
    2022
    Colloquium
    Time: 11:00-12:15
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Dr. Amnon Bar-Shir
    Organizer: Faculty of Chemistry
    Contact: sarah.amzallag@weizmann.ac.il
    Abstract: Luminescent materials with their rich color palettes have revolutionized both sc ... Read more Luminescent materials with their rich color palettes have revolutionized both science and technology through the ability to distinguish between spectrally resolved colors for a wide range of applications from sensing to molecular steganography through high-end electronics and biomedical imaging. Yet, light-based colors suffer from limitations, such as strong scattering and absorbance in opaque media, restricted spectral resolution, photo-bleaching, intolerance for color-palette extendibility and more. Amongst the diverse capabilities and many advantages of Nuclear Magnetic Resonance (spectroscopy and imaging) several are unique, e.g., the sensitivity of the chemical shifts to the chemical environment, the penetrateability of MR signals across opaque objects and the ability to produce three dimensional images of studied subjects. Here, I discuss our recent developments of molecular probes that are capable to generate artificial MR-based colors. To this end, we use synthetic chemistry, nanofabrication, and protein engineering approaches to generate novel molecular formulations (small molecules, nanocrystals (NCs), supramolecular assemblies and proteins) as MRI sensors with unique, advantageous properties (sensitivity, specificity, orthogonality, etc.). I will also discuss how the very same molecular probes can be used to better understand fundamental scientific questions in supramolecular chemistry (e.g., kinetic features of dynamically exchanging molecular systems) and materials science (e.g., understanding and controlling NCs’ formation pathways).
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    Fragmenting the self: brainwide recording and the neurobiology of dissociation

    Date:
    13
    Wednesday
    April
    2022
    Lecture / Seminar
    Time: 12:30
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Dr. Isaac Kauvar
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host-Prof. Ofer Yizhar ofer.yizhar@weizmann.ac.il tel: 6957
    Abstract: Advanced methods now allow fast, cellular-level recording of neural activity acr ... Read more Advanced methods now allow fast, cellular-level recording of neural activity across the mammalian brain, enabling exploration of how brain-wide dynamical patterns might give rise to complex behavioral states, such as the clinically important state of dissociation. We established a dissociation-like state in mice, induced by administration of ketamine or phencyclidine. Large-scale neural recording revealed that these dissociative agents elicited a 1–3-Hz rhythm in layer 5 neurons of retrosplenial cortex, uncoupled from most other brain regions except thalamus. Additionally, using brain-wide intracranial electrical recording in a patient with focal epilepsy, the human experience of dissociation was linked to a similar ~3 Hz rhythm in posteromedial cortex (homologous to mouse retrosplenial cortex), and stimulation of this area induced dissociation.   
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    Role of forces in membrane dynamics and tissue morphogenesis

    Date:
    05
    Tuesday
    April
    2022
    Lecture / Seminar
    Time: 10:00-11:00
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Prof. Marino Zerial
    Organizer: Department of Biomolecular Sciences
    Contact: levana.ayvazo@weizmann.ac.il
    Abstract: Our work has highlighted the function of Rab GTPases as key components for the b ... Read more Our work has highlighted the function of Rab GTPases as key components for the biogenesis, transport and function of cellular membrane organelles. The specificity and directionality of membrane fusion is mediated by Rab GTPases and tethering effectors, such as EEA1, which is recruited on the early endosome membrane and binds to Rab5. EEA1 is a long dimeric coiled-coil tether molecule. Upon binding to its N-terminus, Rab5 induces conformational changes on EEA1, from extended to a more flexible “collapsed” state, giving rise to an effective force. Our recent studies suggest that Rab5 and EEA1 effectively constitute a two-component molecular motor, cyclically converting the free energy of GTP binding and hydrolysis into mechanical work. We are now combining biochemical, quantitative image analysis and 3D primary cell culture approaches to explore the role of Rab GTPases and endocytic mechanisms in liver tissue organization and regeneration. Hepatocytes are polarized cells at the interface of both sinusoidal endothelial and bile canaliculi (BC) networks that transport blood and bile between portal and central vein, respectively. In contrast to simple epithelia, where the cells have a single apical surface facing the lumen of organs, hepatocytes exhibit a multipolar (biaxial) organization, i.e. have multiple apical and basal domains. We studied the mechanism of hepatocyte polarization by using a hepatoblasts culture system. We discovered that, during lumen formation, hepatoblasts create apical protrusions along the tight junction belt that connects them, suggesting that these are responsible for the anisotropic growth of apical lumina. These protrusions form a pattern reminiscent of the bulkheads of boats ships and planes. Similarly, the apical bulkheads of hepatocytes are structural elements which can provide such anisotropy and mechanical stability to the elongating cylindrical lumen under inner pressure.
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    Microbial and Antimicrobial Amyloids in the Fight Against Infections

    Date:
    29
    Tuesday
    March
    2022
    Lecture / Seminar
    Time: 10:00-11:00
    Location: Nella and Leon Benoziyo Building for Biological Sciences
    Lecturer: Prof. Meytal Landau
    Organizer: Department of Biomolecular Sciences
    Contact: levana.ayvazo@weizmann.ac.il
    Abstract: Amyloids are protein fibers with unique and strong structures, known mainly in t ... Read more Amyloids are protein fibers with unique and strong structures, known mainly in the context of neurodegenerative diseases. Surprisingly, amyloid fibers are secreted by species across kingdoms of life, including by microorganisms, and helps their survival and activity. Our laboratory published the first molecular structures of functional bacterial amyloid fibrils, which serve as key “weapons” making infections more aggressive. This exposed new routes for the development of novel antivirulence drugs. In addition, we identified peptides produced across species that provide antimicrobial protection that form amyloid fibrils, and determined their first high resolution structures. This amyloid-antimicrobial link signifies a physiological role in neuroimmunity for human amyloids.
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    The impact of metabolic processes at the brain’s choroid plexus and of the gut microbiome on Alzheimer’s disease manifestation

    Date:
    24
    Thursday
    March
    2022
    Lecture / Seminar
    Time: 16:00
    Title: Student Seminar - PhD Thesis Defense -ZOOM-
    Lecturer: Afroditi Tsitsou-Kampeli
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Zoom link https://weizmann.zoom.us/j/98658552127?pwd=ZkZmWTBkd1AxZ0xPbGlpU3FPUW ... Read more Zoom link https://weizmann.zoom.us/j/98658552127?pwd=ZkZmWTBkd1AxZ0xPbGlpU3FPUWpzUT09 Meeting ID:986 5855 2127 Password:495213
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    Abstract: The immune system and the gut microbiome are becoming major players in chronic n ... Read more The immune system and the gut microbiome are becoming major players in chronic neurodegenerative conditions. One of the key interfaces between the brain and the immune system with an impact on brain function is the choroid plexus (CP). The CP interface is central to the maintenance of brain homeostasis by exerting a plethora of different biological processes. However, in aging and Alzheimer’s disease (AD), interferon type-I (IFN-I) signaling accumulates at the CP and impedes part of its beneficial function by inducing a CP-pro-aging signature. My research contributed to the finding that IFN-I signaling at the CP induces an aging-like signature in microglia and impedes cognitive abilities in middle-aged mice in a microglia-dependent manner. In addition, I demonstrated that the brain-specific enzyme, cholesterol 24-hydroxylase (CYP46A1), is expressed by the CP epithelium and that its product, 24-hydroxycholesterol (24-OH), downregulates CP-pro-inflammatory signatures. Furthermore, in AD, CP CYP46A1 protein levels were decreased in both mice and humans and overexpression of Cyp46a1 at the CP in 5xFAD mice reversed brain inflammation, microglial dysfunction signatures, and cognitive loss. Finally, while the pro-inflammatory cytokine TNF-α impaired CP Cyp46a1 expression in vitro, boosting systemic immunity in vivo increased its levels in an IFNGR2-dependent manner. These results highlight CYP46A1 at the CP as a remote regulator of brain inflammation, which diminishes with neurodegeneration, but is amenable to rescue. Focusing on the gut microbiome, I found that 5xFAD mice devoid of microbiome exhibited a striking decrease of long-term spatial memory deficit and increased synaptic and neuronal survival. Spatial memory deficit in 5xFAD mice kept in germ free (GF) or specific-pathogen free (SPF) conditions, negatively correlated with the abundance of 2-hydroxypyridine, while systemic, chronic supply of 2-hydroxypyridine in SPF 5xFAD mice improved spatial memory deficits in comparison to phosphate-buffered saline (PBS)-supplied 5xFAD mice. Overall, these findings demonstrate a microbiome-dependent effect on AD pathology in the 5xFAD mouse model and suggest a connection between 2-hydroxypyridine and AD manifestation. In general, this research thesis addresses novel aspects of choroid plexus and gut microbiome metabolism and their relation to AD progression. Zoom link https://weizmann.zoom.us/j/98658552127?pwd=ZkZmWTBkd1AxZ0xPbGlpU3FPUWpzUT09 Meeting ID:986 5855 2127 Password:495213
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    Stem Cells, Regeneration and Aging Seminar

    Date:
    15
    Tuesday
    March
    2022
    Lecture / Seminar
    Time: 09:00-10:30
    Title: From single cells to tissues' dynamics in development and ageing
    Location: Max and Lillian Candiotty Building
    Lecturer: Prof. Amos Tanay
    Organizer: Life Sciences
    Contact: karina.yaniv@weizmann.ac.il

    Cracking the olfactory code using behavior

    Date:
    13
    Sunday
    March
    2022
    Lecture / Seminar
    Time: 10:00-11:00
    Title: Hybrid Seminar
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Dmitry Rinberg
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZ ... Read more Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421 Dr. Takashi Kawashima tel:2995 takashi.kawashima@weizmann.ac.il Contact & accessibility issues: naomi.moses@weizmann.ac.il
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    Abstract: Two of the most fundamental questions of sensory neuroscience are: 1) how is sti ... Read more Two of the most fundamental questions of sensory neuroscience are: 1) how is stimulus information represented by neuronal activity? and 2) what features of this activity are read out to guide behavior? The first question has been the subject of a large body of work across different sensory modalities. The second question remains a significant challenge, since one needs to establish a causal link between neuronal activity and behavior. In olfaction, it has been proposed that information about odors is encoded in spatial distribution of receptor activation and the next level mitral/tufted cells, as well as in their relative timing and synchrony. However, the role of different features of neural activity in guiding behavior remains unknown. Using mouse olfaction as a model system, we developed both technological and conceptual approaches to study sensory coding by perturbing neural activity at different levels of information processing during sensory driven behavioral tasks. We developed methods for both one-photon spatiotemporal pattern stimulation using digital mirror devices at the glomerulus level in the olfactory bulb, and two-photon holographic pattern stimulation deeper in the brain, at the level of mitral/tufted cells. Using these techniques, we performed quantitative behavioral experiments to, first, measure psychophysical limits of the readability of different features of the neural code, and, second, to quantify their behavioral relevance. Based on these results, we built a detailed mathematical model of the behavioral relevance of the different features of spatiotemporal neural activity. Our approach can be potentially generalized to other sensory systems. Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421
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    Brain-computer interfaces for basic science

    Date:
    10
    Thursday
    March
    2022
    Lecture / Seminar
    Time: 12:30-13:30
    Title: Hybrid Seminar
    Location: Gerhard M.J. Schmidt Lecture Hall
    Lecturer: Prof. Byron Yu
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Host: Dr. Takashi Kawashima takashi.kawashima@weizmann.ac.il tel: 2995 Contac ... Read more Host: Dr. Takashi Kawashima takashi.kawashima@weizmann.ac.il tel: 2995 Contact & accessibility issues: naomi.moses@weizmann.ac.il
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    Abstract: Abstract: Brain-computer interfaces (BCI) translate neural activity into movemen ... Read more Abstract: Brain-computer interfaces (BCI) translate neural activity into movements of a computer cursor or robotic limb. BCIs are known for their ability to assist paralyzed patients. A lesser known, but increasingly important, use of BCIs is their ability to further our basic scientific understanding of brain function. In particular, BCIs are providing insights into the neural mechanisms underlying sensorimotor control that are currently difficult to obtain using limb movements. In this talk, I will demonstrate how a BCI can be leveraged to study how the brain learns. Specifically, I will address why learning some tasks is easier than others, as well as how populations of neurons change their activity in concert during learning. Brief bio: Byron Yu received the B.S. degree in Electrical Engineering and Computer Sciences from the University of California, Berkeley in 2001. He received the M.S. and Ph.D. degrees in Electrical Engineering in 2003 and 2007, respectively, from Stanford University. From 2007 to 2009, he was a postdoctoral fellow jointly in Electrical Engineering and Neuroscience at Stanford University and at the Gatsby Computational Neuroscience Unit, University College London. He then joined the faculty of Carnegie Mellon University in 2010, where he is a Professor in Electrical & Computer Engineering and Biomedical Engineering, and the Gerard G. Elia Career Development Professor. He is broadly interested in how large populations of neurons process information, from encoding sensory stimuli to driving motor actions. His group develops and applies novel statistical algorithms and uses brain-computer interfaces to study brain function. Link- https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421
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    Distributed views across media: From space to ocean-depths

    Date:
    13
    Sunday
    February
    2022
    Lecture / Seminar
    Time: 11:00
    Location: https://weizmann.zoom.us/j/7621438333?pwd=c0lpdlQzYSthellXWG9rZnM0ZDRFZz09
    Lecturer: Yoav Schechner
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: By economy of scale, imaging sensors can now be deployed densely and operated in ... Read more By economy of scale, imaging sensors can now be deployed densely and operated in a coordinated manner at large numbers in space, air, underwater and on the ground. Such distributed imaging systems enable multi-view setups across heterogeneous media of importance to geoscience. These create new observation modes. One outcome is 4D volumetric spatiotemporal recovery of scatterers in the atmosphere, specifically cloud content (the core of the CloudCT space mission). This is in addition to computed tomography of underwater sediment suspension and atmospheric turbulence distributions. We describe several such systems - demonstrated in the field, including both distributed imaging and the basis of the algorithms to analyze the data.
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    Effects of physical exercise and adult neurogenesis on hippocampal neural codes

    Date:
    10
    Thursday
    February
    2022
    Lecture / Seminar
    Time: 09:00-10:00
    Lecturer: Yoav Rechavi - PhD Thesis Defense on Zoom
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Zoom link-https://weizmann.zoom.us/j/93585241611?pwd=RGsxakU2aElVQ01nbUpuRjVqOWQ ... Read more Zoom link-https://weizmann.zoom.us/j/93585241611?pwd=RGsxakU2aElVQ01nbUpuRjVqOWQ0QT09 Meeting ID: 935 8524 1611 Password: 243908
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    Abstract: ABSTRACT Physical activity plays a vital role in maintaining a healthy brain, au ... Read more ABSTRACT Physical activity plays a vital role in maintaining a healthy brain, augmenting memory and cognition in both humans and animals. Previous studies have identified multiple distinct molecular and cellular factors that mediate these effects, both within the brain and systemically. However, what remains unknown is how exercise affects the neural coding mechanisms that underlie these cognitive and memory abilities. In my work I addressed this question in the context of spatial cognition, and studied how chronic voluntary exercise affects the quality and the long-term stability of hippocampal place codes. I performed longitudinal imaging of calcium activity in the hippocampal CA1 of mice as they repeatedly explored initially novel environments over weeks, and compared the place codes of mice that voluntarily ran on wheels in their home cage to those of sedentary mice. As previously reported, physical activity enhanced adult neurogenesis rates in the hippocampal dentate gyrus in the running group. I found that running increased the firing rates and the information content that place cells carry about position. In addition, I discovered a surprising relationship between physical activity and long-term neural-code stability: although running mice demonstrated an overall more stable place code than sedentary mice, their place code exhibited a higher degree of representational drift when controlling for code quality level. Using a simulated neural network, I found that the combination of both improved code quality and faster representational drift in runners, but neither of these effects alone, could recapitulate my experimental results. Overall, these results imply a role for physical activity in both improving the spatial code and accelerating representational drift in the hippocampus. Zoom link-https://weizmann.zoom.us/j/93585241611?pwd=RGsxakU2aElVQ01nbUpuRjVqOWQ0QT09 Meeting ID: 935 8524 1611 Password: 243908
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    Dissecting temperature sensing and epigenetic switching using mathematical modelling and experiments

    Date:
    08
    Tuesday
    February
    2022
    Lecture / Seminar
    Time: 11:30
    Title: PES Dept. Special Guest Seminar
    Location: Zoom link:https://weizmann.zoom.us/j/97166592605?pwd=NVdrc1k4TDJBSXppTFY1Y0ViVzUxZz09 Meeting ID: 971 6659 2605 Password:782843
    Lecturer: Prof. Martin Howard
    Organizer: Department of Plant and Environmental Sciences
    Contact: david.zeevi@weizmann.ac.il
    Details: Host: Dr.David Zeevi
    Abstract: We are studying the mechanistic basis of epigenetic regulation in the Polycomb s ... Read more We are studying the mechanistic basis of epigenetic regulation in the Polycomb system, a vital epigenetic silencing pathway that is widely conserved from flies to plants to humans. We use the process of vernalization in plants in our experiments, which involves memory of winter cold to permit flowering only when winter has passed via quantitative epigenetic silencing of the floral repressor FLC. Utilising this system has numerous advantages, including slow dynamics and the ability to read out mitotic heritability of expression states through clonal cell files in the roots. Using mathematical modelling and experiments (including ChIP and fluorescent reporter imaging), we have shown that FLC cold-induced silencing is essentially an all-or-nothing (bistable) digital process. The quantitative nature of vernalization is generated by digital chromatin-mediated FLC silencing in a subpopulation of cells whose number increases with the duration of cold. We have further shown that Polycomb-based epigenetic memory is indeed stored locally in the chromatin (in cis) via a dual fluorescent labelling approach. I will also discuss how further predictions from the modelling, including opposing chromatin modification states and extra protein memory storage elements, are being investigated. I will also discuss the mechanisms by which long term fluctuating temperature signals are sensed before being converted into digital chromatin states for long term memory storage.
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    Skin stem cells in tissue regeneration and tumor formation

    Date:
    03
    Thursday
    February
    2022
    Lecture / Seminar
    Time: 14:00-15:00
    Location: Max and Lillian Candiotty Building
    Lecturer: Prof. Yaron Fuchs
    Organizer: Dwek Institute for Cancer Therapy Research
    Contact: michal.av@weizmann.ac.il
    Details: https://weizmann.zoom.us/j/5065402023?pwd=a3Z6KzRCU0xJaUFoM2Y5emZwZm1oZz09

    Theory of neural perturbome

    Date:
    01
    Tuesday
    February
    2022
    Lecture / Seminar
    Time: 12:30
    Title: ZOOM
    Lecturer: Prof. Claudia Clopath
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Seminar via Zoom Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3Smp ... Read more Seminar via Zoom Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421 Host: Dr. Takashi Kawashima takashi.kawashima@weizmann.ac.il tel: 2995
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    Abstract: To unravel the functional properties of the brain, we need to untangle how neur ... Read more To unravel the functional properties of the brain, we need to untangle how neurons interact with each other and coordinate in large-scale recurrent networks. One way to address this question is to measure the functional influence of individual neurons on each other by perturbing them in vivo. Application of such single-neuron perturbations in mouse visual cortex has recently revealed feature- specific suppression between excitatory neurons, despite the presence of highly specific excitatory connectivity, which was deemed to underlie feature-specific amplification. Here, we studied which connectivity profiles are consistent with these seemingly contradictory observations, by modeling the effect of single-neuron perturbations in large-scale neuronal networks. Our numerical simulations and mathematical analysis revealed that, contrary to the prima facie assumption, neither inhibition dominance nor broad inhibition alone were sufficient to explain the experimental findings; instead, strong and functionally specific excitatory–inhibitory connectivity was necessary, consistent with recent findings in the primary visual cortex of rodents. Such networks had a higher capacity to encode and decode natural images, and this was accompanied by the emergence of response gain nonlinearities at the population level. Our study provides a general computational framework to investigate how single-neuron perturbations are linked to cortical connectivity and sensory coding and paves the road to map the perturbome of neuronal networks in future studies. Zoom Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421
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    BOOSTING CAR T CELL EFFICACY BY MODULATION OF THE MICROENVIRONMENT IN BRAIN TUMORS

    Date:
    20
    Thursday
    January
    2022
    Lecture / Seminar
    Time: 14:00
    Location: Max and Lillian Candiotty Building
    Lecturer: Prof. Dinorah Friedmann-Morvinski
    Organizer: Dwek Institute for Cancer Therapy Research
    Contact: michal.av@weizmann.ac.il
    Details: https://weizmann.zoom.us/j/5065402023?pwd=a3Z6KzRCU0xJaUFoM2Y5emZwZm1oZz09

    Student Seminar on Zoom - PhD Thesis Defense by Maya Amitai

    Date:
    19
    Wednesday
    January
    2022
    Lecture / Seminar
    Time: 10:00-11:00
    Lecturer: Maya Amitai, MD, PhD
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Student Seminar - PhD Thesis Defense Zoom link: https://weizmann.zoom.us/j/9109 ... Read more Student Seminar - PhD Thesis Defense Zoom link: https://weizmann.zoom.us/j/91093085114?pwd=RVBKbEZXbjlsaVZrUVRuNThtVHB1UT09 Meeting ID: 910 9308 5114 Password : 419366
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    Abstract: Depression and anxiety disorders are among the most common childhood psychiatric ... Read more Depression and anxiety disorders are among the most common childhood psychiatric disorders. Selective serotonin reuptake inhibitors (SSRIs) are generally considered first-line treatment for both depression and anxiety in this age group. However, 30%–40% of all patients who receive a sufficient dose and duration of treatment fail to respond. Moreover, SSRI use is frequently associated with adverse events (AEs), including activation symptoms, manic switch and increased suicidal behavior (SBs). These are particularly relevant in pediatric populations because of concerns about the suicide threat of SSRIs, resulting in a "black-box" warning. There are currently no biomarkers that can predict treatment response or AEs. Identification of such biomarkers could help to maximize the benefit-risk ratio for the use of SSRIs and speed the matching of treatment to patient. Given the fact that depression / anxiety risk is influenced by both genetic and environmental factors and that both state and trait factors will be important in treatment response prediction, a multidimensional biomarker panel covering several levels of biological information would likely be necessary. The main objective of this research thesis is to identify biomarkers that will aid in the prediction of response and suicidal and other AEs of SSRI treatment in children and adolescents treated for depression and/or anxiety disorders. We examined the involvement of specific biomarkers (miRNA’s, DNA methylation, single nucleotide polymorphism [SNP's] and metabolites) in the response to SSRIs treatment in children and adolescents and in the differences observed between individuals exhibiting response or non-response/AEs to treatment with SSRIs. Two hundred and sixty-six children and adolescents with depression and/or anxiety disorders were recruited and treated with fluoxetine. The overall response rate was 55%. Several targets from several biological domains (DNA methylation profile, miRNA’s and metabolites) were identifies as differentially expressed between responders and non-responders at baseline test. Pathway analysis of the predicted targets was carried out to assess their putative biological functions. Interestingly, when combining targets from the four biological domains, the targets were predicted to regulate specific biological pathways associated with immune system pathways and/or developmental pathways. Dysregulation of complex gene networks in the developing brain is thought to underlie depression with childhood or adolescent onset. Thus, the identified molecules might play critical roles in transcriptional networks related to treatment response and AEs. These transcriptional networks are particularly relevant to the developing human brain and to neurodevelopmental disorders with childhood/adolescent onset, such as depression and anxiety disorders. Zoom link: https://weizmann.zoom.us/j/91093085114?pwd=RVBKbEZXbjlsaVZrUVRuNThtVHB1UT09 Meeting ID: 910 9308 5114 Password : 419366
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    The immune system-gut-brain axis: environmental impacts on aging and neurological disorders

    Date:
    16
    Sunday
    January
    2022
    Lecture / Seminar
    Time: 11:00-12:30
    Location: Wolfson Building for Biological Research
    Lecturer: Dr. Eran Blacher
    Organizer: Department of Molecular Cell Biology
    Contact: michal.ovadia@weizmann.ac.il
    Details: Zoom link: https://weizmann.zoom.us/j/93005753989?pwd=WllWVlNsUnRPSnVEemRLUUZvU0 ... Read more Zoom link: https://weizmann.zoom.us/j/93005753989?pwd=WllWVlNsUnRPSnVEemRLUUZvU0RLdz09 Meeting ID: 930 0575 3989 Password: 599484
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    Gallery: The immune system-gut-brain axis: environmental impacts on aging and neurological disorders Gallery
    The immune system-gut-brain axis: environmental impacts on aging and neurological disorders Lecture / Seminar website

    Direct Imaging of Planet Formation

    Date:
    16
    Sunday
    January
    2022
    Lecture / Seminar
    Time: 11:00-12:00
    Location: https://weizmann.zoom.us/j/7621438333?pwd=c0lpdlQzYSthellXWG9rZnM0ZDRFZz09
    Lecturer: Sivan Ginzburg
    Organizer: Department of Earth and Planetary Sciences
    Contact: dalia.madhala@weizmann.ac.il
    Abstract: The vast majority of detected planets are observed indirectly, using their small ... Read more The vast majority of detected planets are observed indirectly, using their small perturbation on the light emitted by the host stars. In recent years, however, the world's largest ground based telescopes have succeeded in directly imaging the light coming from some planets themselves. I will present our comprehensive theory for the mass, luminosity, and spin of gas giant planets during their final stages of formation - when they simultaneously contract and accrete gas from a disk. I will apply this theory to the luminosity and spectrum obtained by the novel direct-imaging technique, highlighting the recently discovered PDS 70 system, where two planets were directly observed during formation for the first time.
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    Zoom seminar -Diversity of dopamine neurons: multi-agent reinforcement learning

    Date:
    11
    Tuesday
    January
    2022
    Lecture / Seminar
    Time: 16:00-17:00
    Lecturer: Prof. Naoshige Uchida
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Zoom Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeH ... Read more Zoom Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421 Host: Dr. Takashi Kawashima takashi.kawashima@weizmann.ac.il tel - 2995
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    Abstract: Dopamine regulates multiple brain functions including learning, motivation and m ... Read more Dopamine regulates multiple brain functions including learning, motivation and movement. Furthermore, the striatum, a major target of dopamine neurons, is parceled into multiple subregions that are associated with different types of behavior, such as Pavlovian, goal-directed, and habitual behaviors. An important question in the field is how dopamine regulates these diverse functions. It has been thought that midbrain dopamine neurons broadcast reward prediction error signals to drive reinforcement learning. However, recent studies have found more diverse dopamine signals than originally thought. How can we reconcile these results? In this talk, I will discuss our recent studies characterizing diverse dopamine signals, and how these findings can be understood in a coherent theoretical framework. Zoom Link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421
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    Circuits for decisions, attention and working memory in the primate visual system

    Date:
    10
    Monday
    January
    2022
    Lecture / Seminar
    Time: 14:00-16:00
    Location: https://weizmann.zoom.us/j/91943040474?pwd=b0pya3luOGp6TVl1NGFuMUp4Ulo0QT09
    Lecturer: Dr. Leor Katz
    Organizer: Department of Brain Sciences
    Contact: shakked.ganor@weizmann.ac.il
    Abstract: Making decisions, attending to certain items, and manipulating information in wo ... Read more Making decisions, attending to certain items, and manipulating information in working memory are fundamental behaviors that rely on specific neural circuitry. Throughout my research I have contributed to understanding such behaviors in human and in nonhuman primates but found that despite tremendous advances in the field, we still lack a mechanistic understanding of what goes wrong in conditions such as dementia or autism. My long-term research goal is to determine the circuits that support cognitive behavior, in health and disease. In my talk, I present three key contributions I have made towards uncovering neuronal circuits for cognition in the macaque, an animal model whose neural circuitry affords unique insight into human brain function. First, I demonstrate the utility of rigorous psychophysical frameworks in determining the causal contribution of key brain regions to behavior in a perceptual decision-making task. Next, I describe how causal manipulations of brain areas involved in attentional control can be used to identify hitherto unknown areas and reveal new functional circuits in support of selective attention and object recognition. Finally, I show how computational analyses of population data reveal circuits within circuits with distinct roles in supporting working memory. I end the talk by presenting my future research directions and approach: to leverage my experience studying how we select from external information (from sensory signals) to investigate how we select from internal information (from information stored in visual working memory). By blending theory-driven experiments with large-scale electrophysiological recording and circuit-specific causal manipulations in behaving macaques, I aim to uncover how we select relevant information from working memory, and equally important, how we fail to do so when struck by disorders of executive or memory function.
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    Zoom Seminar - Using deep neural networks as cognitive models for how brains act in the natural world

    Date:
    04
    Tuesday
    January
    2022
    Lecture / Seminar
    Time: 12:30-13:30
    Lecturer: Prof. Uri Hasson
    Organizer: Department of Brain Sciences
    Contact: naomi.moses@weizmann.ac.il
    Details: Zoom link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVe ... Read more Zoom link: https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421 Host: Dr. Takashi Kawashima takashi.kawashima@weizmann.ac.il tel:2995
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    Abstract: Naturalistic experimental paradigms in neuroimaging arose from a pressure to tes ... Read more Naturalistic experimental paradigms in neuroimaging arose from a pressure to test the validity of models we derive from highly controlled experiments in real-world contexts. In many cases, however, such efforts led to the realization that models developed under particular experimental manipulations failed to capture much variance outside the context of that manipulation. The critique of non-naturalistic experiments is not a recent development; it echoes a persistent and subversive thread in the history of modern psychology. The brain has evolved to guide behavior in a multidimensional world with many interacting variables. The assumption that artificially decoupling and manipulating these variables will lead to a good understanding of the brain may be untenable. Recent advances in artificial neural networks provide an alternative computational framework to model cognition in natural contexts. In contrast to the simplified and interpretable hypotheses we test in the lab, these models do not learn simple, human-interpretable rules or representations of the world. Instead, they use local computations to interpolate over task-relevant manifolds in high-dimensional parameter space. Counterintuitively, over-parameterized deep neural models are parsimonious and straightforward, as they provide a versatile, robust solution for learning a diverse set of functions in natural contexts. Naturalistic paradigms should not be deployed as an afterthought if we hope to build models of brain and behavior that extend beyond the laboratory into the real world. In my talk, I will discuss the relevance of deep neural models to cognition in the context of natural language and deep language models. Zoom link- https://weizmann.zoom.us/j/95406893197?pwd=REt5L1g3SmprMUhrK3dpUDJVeHlrZz09 Meeting ID: 954 0689 3197 Password: 750421
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