All events, 2024

Mapping the world around us: A topology-preserved schema of space that supports goal-directed navigation

Lecture
Date:
Tuesday, February 20, 2024
Hour: 12:30
Location:
Gerhard M.J. Schmidt Lecture Hall
Dr. Raunak Basu
|
Edmond and Lily Safra Center for Brain Sciences The Hebrew University of Jerusalem

Successful goal-directed navigation requires estimating one’s current position in the environment, representing the future goal location, and maintaining a map that preserves the topological relationship between positions. In addition, we often need to implement similar navigational strategies in a continuously changing environment, thereby necessitating certain invariance in the underlying spatial maps. Previous research has identified neurons in the hippocampus and parahippocampal cortices that fire specifically when an animal visits a particular location, implying the presence of a spatial map in the brain. However, this map largely encodes the current position of an animal and is context-dependent, whereby changing the room or shape of the arena results in a new map orthogonal to the previous one. These observations raise the question, are there other spatial maps that fulfill the cognitive requirements necessary for goal-directed navigation? Using a goal-directed navigation task with multiple reward locations, we observed that neurons in the orbitofrontal cortex (OFC) exhibit distinct firing patterns depending on the goal location, and this goal-specific OFC activity originates even before the onset of the journey. Further, the difference in the ensemble firing patterns representing two target locations is proportional to the physical distance between these locations, implying the preservation of spatial topology. Finally, carrying out the task across different spatial contexts revealed that the mapping of target locations in the OFC is largely preserved and that the maps formed in two different contexts occupy similar neural subspaces and could be aligned by a linear transformation. Taken together, the OFC forms a topology-preserved schema of spatial locations that is used to represent the future spatial goal, making it a potentially crucial brain region for planning context-invariant goal-directed navigational strategies.

The role of the corpus callosum in interhemispheric communication

Lecture
Date:
Wednesday, February 14, 2024
Hour: 14:00 - 15:00
Location:
The David Lopatie Hall of Graduate Studies
Yael Oran-PhD Thesis Defense
|
Prof. Ilan Lampl Lab Dept of Brain Sciences

Interhemispheric communication is a comprehensive concept that involves both the synchronization of neural activity as well as the integration of sensory information across the two brain hemispheres. In this work, we explored these properties in the somatosensory system of the mouse brain. We show that during spontaneous activity in awake animals,  robust interhemispheric correlations of both spiking and synaptic activities that are reduced during whisking compared to quiet wakefulness. And that the state-dependent correlations between the hemispheres stem from the state-depended nature of the corpus callosum activity. Further, to understand how sensory information is integrated across the brain's hemispheres, we studied bilateral and ipsilateral responses to passive whisker stimulation using widefield imaging and then employed a virtual tunnel environment to explore bilateral integration in active whisking

Mechanistic insights into ‘brainwashing’ 

Lecture
Date:
Tuesday, February 13, 2024
Hour: 12:30 - 13:30
Location:
Gerhard M.J. Schmidt Lecture Hall
Prof. Jonathan Kipnis
|
Dept of Pathology and Immunology Washington University School of Medicine in St. Louis

One molecular- and one circuit-level insight into cognition from studying Drosophila

Lecture
Date:
Tuesday, January 30, 2024
Hour: 12:30 - 13:30
Location:
Gerhard M.J. Schmidt Lecture Hall
Prof. Gaby Maimon
|
HHMI, The Rockfeller University, NY

A major goal of cognitive neuroscience is to clarify the functions of central brain regions. Over the past decade, the high-level functional architecture of a region in the middle of the insect brain––the central complex––has come into focus. I will start by briefly summarizing our understanding of the central complex as a microcomputer that calculates the values of angles and two-dimensional vectors important for guiding navigational behavior. I will then describe some recent findings on this brain region, revealing (1) how neuronal calcium spikes, mediated by T-type calcium channels, augment spatial-vector calculations and (2) how an angular goal signal is converted into a locomotor steering signal. These results provide inspiration for better understanding the roles of calcium spikes and goal signals in mammalian brains.

Non-canonical circuits for olfaction

Lecture
Date:
Tuesday, January 16, 2024
Hour: 12:30 - 13:30
Location:
Gerhard M.J. Schmidt Lecture Hall
Dr. Dan Rokni
|
Dept of Medical Neurobiology, IMRIC The Hebrew University of Jerusalem, Ein Kerem

: I’ll describe two projects: In the first, we examined the circuitry that underlies olfaction in a mouse model with severe developmental degeneration of the OB. The olfactory bulb (OB) is a critical component of mammalian olfactory neuroanatomy. Beyond being the first and sole relay station for olfactory information to the rest of the brain, it also contains elaborate stereotypical circuitry that is considered essential for olfaction. In our mouse model, a developmental collapse of local blood vessels leads to degeneration of the OB. Mice with degenerated OBs could perform odor-guided tasks and even responded normally to innate olfactory cues. I will describe the aberrant circuitry that supports functional olfaction in these mice. The second project focusses on the nucleus of the lateral olfactory tract. This amygdaloid nucleus is typically considered part of the olfactory cortex, yet almost nothing is known about its function, connectivity, and physiology. I will describe our approach to studying this intriguing structure and will present some of its cellular and synaptic properties that may guide hypotheses about its function.

Immunoception: Brain Representation and Control of Immunity

Lecture
Date:
Tuesday, January 9, 2024
Hour: 13:00
Location:
Wolfson Building for Biological Research
Prof. Asya Rolls
|
HHMI-Wellcome Scholar Rappaport Institute for Medical Research TECHNION Haifa

To function as an integrated entity, the organism must synchronize between behavior and physiology. Our research focuses on probing this synchronization through the lens of the brain-immune system interface. The immune system, pivotal in preserving the organism's integrity, is also a sensitive barometer of its overall state. I will discuss the emerging understanding of how the brain represents the state of the immune system and the specific neural mechanisms that enable the brain to orchestrate immune responses.

Olfactory information processing: timing, sequences, geometry  and relevance

Lecture
Date:
Thursday, January 4, 2024
Hour: 12:30 - 13:30
Location:
Gerhard M.J. Schmidt Lecture Hall
Prof. Dmitry Rinberg
|
Dept of Neuroscience and Physiology Neuroscience Institute NYU

A paradigm shift in GPCR recruitment and activity: GPCR Voltage Dependence Controls Neuronal Plasticity and Behavior

Lecture
Date:
Tuesday, January 2, 2024
Hour:
Location:
Gerhard M.J. Schmidt Lecture Hall
Prof. Moshe Parnas
|
Dept of Physiology and Pharmacology Tel Aviv University

: G-protein coupled receptors (GPCRs) play a paramount role in diverse brain functions. Twenty years ago, GPCR activity was shown to be regulated by membrane potential in vitro, but whether the voltage dependence of GPCRs contributes to neuronal coding and behavioral output under physiological conditions in vivo has never been demonstrated. We show in two different processes that muscarinic GPCR mediated neuromodulation in vivo is voltage dependent. First, we show that muscarinic type A receptors (mAChR-A) mediated neuronal potentiation is voltage dependent. This potentiation voltage dependency is abolished in mutant flies expressing a voltage independent receptor. Most important, muscarinic receptor voltage independence caused a strong behavioral effect of increased odor habituation. Second, we show that muscarinic type B receptors (mAChR-B) voltage dependency is required for both efficient and accurate learning and memory. Normally, to prevent non-specific olfactory learning and memory, mAChR-B activity suppress both signals that are required for plasticity. Behavior experiments demonstrate that mAChR-B knockdown impairs olfactory learning by inducing undesired changes to the valence of an odor that was not associated with the reinforcer. On the other hand, mAChR-B voltage dependence prevents mAChR-B to interfere with plasticity in neurons that are required for the learning and memory process. Indeed, generating flies with a voltage independent mAChR-B resulted in impaired learning. Thus, we provide the very first demonstrations of physiological roles for the voltage dependency of GPCRs by demonstrating crucial involvement of GPCR voltage dependence in neuronal plasticity and behavior. As such, our findings create a paradigm shift in our thinking on GPCR recruitment and activity. Together, we suggest that GPCR voltage dependency plays a role in many diverse neuronal functions including learning and memory and may serve as a target for novel drug development. Light refreshments before the seminar.

Pages

All events, 2024

Mapping the world around us: A topology-preserved schema of space that supports goal-directed navigation

Lecture
Date:
Tuesday, February 20, 2024
Hour: 12:30
Location:
Gerhard M.J. Schmidt Lecture Hall
Dr. Raunak Basu
|
Edmond and Lily Safra Center for Brain Sciences The Hebrew University of Jerusalem

Successful goal-directed navigation requires estimating one’s current position in the environment, representing the future goal location, and maintaining a map that preserves the topological relationship between positions. In addition, we often need to implement similar navigational strategies in a continuously changing environment, thereby necessitating certain invariance in the underlying spatial maps. Previous research has identified neurons in the hippocampus and parahippocampal cortices that fire specifically when an animal visits a particular location, implying the presence of a spatial map in the brain. However, this map largely encodes the current position of an animal and is context-dependent, whereby changing the room or shape of the arena results in a new map orthogonal to the previous one. These observations raise the question, are there other spatial maps that fulfill the cognitive requirements necessary for goal-directed navigation? Using a goal-directed navigation task with multiple reward locations, we observed that neurons in the orbitofrontal cortex (OFC) exhibit distinct firing patterns depending on the goal location, and this goal-specific OFC activity originates even before the onset of the journey. Further, the difference in the ensemble firing patterns representing two target locations is proportional to the physical distance between these locations, implying the preservation of spatial topology. Finally, carrying out the task across different spatial contexts revealed that the mapping of target locations in the OFC is largely preserved and that the maps formed in two different contexts occupy similar neural subspaces and could be aligned by a linear transformation. Taken together, the OFC forms a topology-preserved schema of spatial locations that is used to represent the future spatial goal, making it a potentially crucial brain region for planning context-invariant goal-directed navigational strategies.

The role of the corpus callosum in interhemispheric communication

Lecture
Date:
Wednesday, February 14, 2024
Hour: 14:00 - 15:00
Location:
The David Lopatie Hall of Graduate Studies
Yael Oran-PhD Thesis Defense
|
Prof. Ilan Lampl Lab Dept of Brain Sciences

Interhemispheric communication is a comprehensive concept that involves both the synchronization of neural activity as well as the integration of sensory information across the two brain hemispheres. In this work, we explored these properties in the somatosensory system of the mouse brain. We show that during spontaneous activity in awake animals,  robust interhemispheric correlations of both spiking and synaptic activities that are reduced during whisking compared to quiet wakefulness. And that the state-dependent correlations between the hemispheres stem from the state-depended nature of the corpus callosum activity. Further, to understand how sensory information is integrated across the brain's hemispheres, we studied bilateral and ipsilateral responses to passive whisker stimulation using widefield imaging and then employed a virtual tunnel environment to explore bilateral integration in active whisking

Mechanistic insights into ‘brainwashing’ 

Lecture
Date:
Tuesday, February 13, 2024
Hour: 12:30 - 13:30
Location:
Gerhard M.J. Schmidt Lecture Hall
Prof. Jonathan Kipnis
|
Dept of Pathology and Immunology Washington University School of Medicine in St. Louis

One molecular- and one circuit-level insight into cognition from studying Drosophila

Lecture
Date:
Tuesday, January 30, 2024
Hour: 12:30 - 13:30
Location:
Gerhard M.J. Schmidt Lecture Hall
Prof. Gaby Maimon
|
HHMI, The Rockfeller University, NY

A major goal of cognitive neuroscience is to clarify the functions of central brain regions. Over the past decade, the high-level functional architecture of a region in the middle of the insect brain––the central complex––has come into focus. I will start by briefly summarizing our understanding of the central complex as a microcomputer that calculates the values of angles and two-dimensional vectors important for guiding navigational behavior. I will then describe some recent findings on this brain region, revealing (1) how neuronal calcium spikes, mediated by T-type calcium channels, augment spatial-vector calculations and (2) how an angular goal signal is converted into a locomotor steering signal. These results provide inspiration for better understanding the roles of calcium spikes and goal signals in mammalian brains.

Non-canonical circuits for olfaction

Lecture
Date:
Tuesday, January 16, 2024
Hour: 12:30 - 13:30
Location:
Gerhard M.J. Schmidt Lecture Hall
Dr. Dan Rokni
|
Dept of Medical Neurobiology, IMRIC The Hebrew University of Jerusalem, Ein Kerem

: I’ll describe two projects: In the first, we examined the circuitry that underlies olfaction in a mouse model with severe developmental degeneration of the OB. The olfactory bulb (OB) is a critical component of mammalian olfactory neuroanatomy. Beyond being the first and sole relay station for olfactory information to the rest of the brain, it also contains elaborate stereotypical circuitry that is considered essential for olfaction. In our mouse model, a developmental collapse of local blood vessels leads to degeneration of the OB. Mice with degenerated OBs could perform odor-guided tasks and even responded normally to innate olfactory cues. I will describe the aberrant circuitry that supports functional olfaction in these mice. The second project focusses on the nucleus of the lateral olfactory tract. This amygdaloid nucleus is typically considered part of the olfactory cortex, yet almost nothing is known about its function, connectivity, and physiology. I will describe our approach to studying this intriguing structure and will present some of its cellular and synaptic properties that may guide hypotheses about its function.

Immunoception: Brain Representation and Control of Immunity

Lecture
Date:
Tuesday, January 9, 2024
Hour: 13:00
Location:
Wolfson Building for Biological Research
Prof. Asya Rolls
|
HHMI-Wellcome Scholar Rappaport Institute for Medical Research TECHNION Haifa

To function as an integrated entity, the organism must synchronize between behavior and physiology. Our research focuses on probing this synchronization through the lens of the brain-immune system interface. The immune system, pivotal in preserving the organism's integrity, is also a sensitive barometer of its overall state. I will discuss the emerging understanding of how the brain represents the state of the immune system and the specific neural mechanisms that enable the brain to orchestrate immune responses.

Olfactory information processing: timing, sequences, geometry  and relevance

Lecture
Date:
Thursday, January 4, 2024
Hour: 12:30 - 13:30
Location:
Gerhard M.J. Schmidt Lecture Hall
Prof. Dmitry Rinberg
|
Dept of Neuroscience and Physiology Neuroscience Institute NYU

A paradigm shift in GPCR recruitment and activity: GPCR Voltage Dependence Controls Neuronal Plasticity and Behavior

Lecture
Date:
Tuesday, January 2, 2024
Hour:
Location:
Gerhard M.J. Schmidt Lecture Hall
Prof. Moshe Parnas
|
Dept of Physiology and Pharmacology Tel Aviv University

: G-protein coupled receptors (GPCRs) play a paramount role in diverse brain functions. Twenty years ago, GPCR activity was shown to be regulated by membrane potential in vitro, but whether the voltage dependence of GPCRs contributes to neuronal coding and behavioral output under physiological conditions in vivo has never been demonstrated. We show in two different processes that muscarinic GPCR mediated neuromodulation in vivo is voltage dependent. First, we show that muscarinic type A receptors (mAChR-A) mediated neuronal potentiation is voltage dependent. This potentiation voltage dependency is abolished in mutant flies expressing a voltage independent receptor. Most important, muscarinic receptor voltage independence caused a strong behavioral effect of increased odor habituation. Second, we show that muscarinic type B receptors (mAChR-B) voltage dependency is required for both efficient and accurate learning and memory. Normally, to prevent non-specific olfactory learning and memory, mAChR-B activity suppress both signals that are required for plasticity. Behavior experiments demonstrate that mAChR-B knockdown impairs olfactory learning by inducing undesired changes to the valence of an odor that was not associated with the reinforcer. On the other hand, mAChR-B voltage dependence prevents mAChR-B to interfere with plasticity in neurons that are required for the learning and memory process. Indeed, generating flies with a voltage independent mAChR-B resulted in impaired learning. Thus, we provide the very first demonstrations of physiological roles for the voltage dependency of GPCRs by demonstrating crucial involvement of GPCR voltage dependence in neuronal plasticity and behavior. As such, our findings create a paradigm shift in our thinking on GPCR recruitment and activity. Together, we suggest that GPCR voltage dependency plays a role in many diverse neuronal functions including learning and memory and may serve as a target for novel drug development. Light refreshments before the seminar.

Pages

All events, 2024

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All events, 2024

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