TopicNeuroscience
Content Overview
90Total items
50Seminars
40ePosters

Latest

SeminarNeuroscience

Decoding stress vulnerability

Stamatina Tzanoulinou
University of Lausanne, Faculty of Biology and Medicine, Department of Biomedical Sciences
Feb 20, 2026

Although stress can be considered as an ongoing process that helps an organism to cope with present and future challenges, when it is too intense or uncontrollable, it can lead to adverse consequences for physical and mental health. Social stress specifically, is a highly prevalent traumatic experience, present in multiple contexts, such as war, bullying and interpersonal violence, and it has been linked with increased risk for major depression and anxiety disorders. Nevertheless, not all individuals exposed to strong stressful events develop psychopathology, with the mechanisms of resilience and vulnerability being still under investigation. During this talk, I will identify key gaps in our knowledge about stress vulnerability and I will present our recent data from our contextual fear learning protocol based on social defeat stress in mice.

SeminarNeuroscience

Astrocytes: From Metabolism to Cognition

Juan P. Bolanos
Professor of Biochemistry and Molecular Biology, University of Salamanca
Oct 3, 2025

Different brain cell types exhibit distinct metabolic signatures that link energy economy to cellular function. Astrocytes and neurons, for instance, diverge dramatically in their reliance on glycolysis versus oxidative phosphorylation, underscoring that metabolic fuel efficiency is not uniform across cell types. A key factor shaping this divergence is the structural organization of the mitochondrial respiratory chain into supercomplexes. Specifically, complexes I (CI) and III (CIII) form a CI–CIII supercomplex, but the degree of this assembly varies by cell type. In neurons, CI is predominantly integrated into supercomplexes, resulting in highly efficient mitochondrial respiration and minimal reactive oxygen species (ROS) generation. Conversely, in astrocytes, a larger fraction of CI remains unassembled, freely existing apart from CIII, leading to reduced respiratory efficiency and elevated mitochondrial ROS production. Despite this apparent inefficiency, astrocytes boast a highly adaptable metabolism capable of responding to diverse stressors. Their looser CI–CIII organization allows for flexible ROS signaling, which activates antioxidant programs via transcription factors like Nrf2. This modular architecture enables astrocytes not only to balance energy production but also to support neuronal health and influence complex organismal behaviors.

SeminarNeuroscience

Neurobiological constraints on learning: bug or feature?

Cian O’Donell
Ulster University
Jun 11, 2025

Understanding how brains learn requires bridging evidence across scales—from behaviour and neural circuits to cells, synapses, and molecules. In our work, we use computational modelling and data analysis to explore how the physical properties of neurons and neural circuits constrain learning. These include limits imposed by brain wiring, energy availability, molecular noise, and the 3D structure of dendritic spines. In this talk I will describe one such project testing if wiring motifs from fly brain connectomes can improve performance of reservoir computers, a type of recurrent neural network. The hope is that these insights into brain learning will lead to improved learning algorithms for artificial systems.

SeminarNeuroscience

Decoding ketamine: Neurobiological mechanisms underlying its rapid antidepressant efficacy

Zanos Panos
Translational Neuropharmacology Lab, University of Cyprus, Center for Applied Neurosience & Department of Psychology, Nicosia, Cyprus
Apr 4, 2025

Unlike traditional monoamine-based antidepressants that require weeks to exert effects, ketamine alleviates depression within hours, though its clinical use is limited by side effects. While ketamine was initially thought to work primarily through NMDA receptor (NMDAR) inhibition, our research reveals a more complex mechanism. We demonstrate that NMDAR inhibition alone cannot explain ketamine's sustained antidepressant effects, as other NMDAR antagonists like MK-801 lack similar efficacy. Instead, the (2R,6R)-hydroxynorketamine (HNK) metabolite appears critical, exhibiting antidepressant effects without ketamine's side effects. Paradoxically, our findings suggest an inverted U-shaped dose-response relationship where excessive NMDAR inhibition may actually impede antidepressant efficacy, while some level of NMDAR activation is necessary. The antidepressant actions of ketamine and (2R,6R)-HNK require AMPA receptor activation, leading to synaptic potentiation and upregulation of AMPA receptor subunits GluA1 and GluA2. Furthermore, NMDAR subunit GluN2A appears necessary and possibly sufficient for these effects. This research establishes NMDAR-GluN2A activation as a common downstream effector for rapid-acting antidepressants, regardless of their initial targets, offering promising directions for developing next-generation antidepressants with improved efficacy and reduced side effects.

SeminarNeuroscience

Mapping the neural dynamics of dominance and defeat

Annegret Falkner
Princeton Neuroscience Institute, USA
Dec 12, 2024

Social experiences can have lasting changes on behavior and affective state. In particular, repeated wins and losses during fighting can facilitate and suppress future aggressive behavior, leading to persistent high aggression or low aggression states. We use a combination of techniques for multi-region neural recording, perturbation, behavioral analysis, and modeling to understand how nodes in the brain’s subcortical “social decision-making network” encode and transform aggressive motivation into action, and how these circuits change following social experience.

SeminarNeuroscience

The Brain Prize winners' webinar

Larry Abbott, Haim Sompolinsky, Terry Sejnowski
Columbia University; Harvard University / Hebrew University; Salk Institute
Nov 30, 2024

This webinar brings together three leaders in theoretical and computational neuroscience—Larry Abbott, Haim Sompolinsky, and Terry Sejnowski—to discuss how neural circuits generate fundamental aspects of the mind. Abbott illustrates mechanisms in electric fish that differentiate self-generated electric signals from external sensory cues, showing how predictive plasticity and two-stage signal cancellation mediate a sense of self. Sompolinsky explores attractor networks, revealing how discrete and continuous attractors can stabilize activity patterns, enable working memory, and incorporate chaotic dynamics underlying spontaneous behaviors. He further highlights the concept of object manifolds in high-level sensory representations and raises open questions on integrating connectomics with theoretical frameworks. Sejnowski bridges these motifs with modern artificial intelligence, demonstrating how large-scale neural networks capture language structures through distributed representations that parallel biological coding. Together, their presentations emphasize the synergy between empirical data, computational modeling, and connectomics in explaining the neural basis of cognition—offering insights into perception, memory, language, and the emergence of mind-like processes.

SeminarNeuroscience

Decomposing motivation into value and salience

Philippe Tobler
University of Zurich
Nov 1, 2024

Humans and other animals approach reward and avoid punishment and pay attention to cues predicting these events. Such motivated behavior thus appears to be guided by value, which directs behavior towards or away from positively or negatively valenced outcomes. Moreover, it is facilitated by (top-down) salience, which enhances attention to behaviorally relevant learned cues predicting the occurrence of valenced outcomes. Using human neuroimaging, we recently separated value (ventral striatum, posterior ventromedial prefrontal cortex) from salience (anterior ventromedial cortex, occipital cortex) in the domain of liquid reward and punishment. Moreover, we investigated potential drivers of learned salience: the probability and uncertainty with which valenced and non-valenced outcomes occur. We find that the brain dissociates valenced from non-valenced probability and uncertainty, which indicates that reinforcement matters for the brain, in addition to information provided by probability and uncertainty alone, regardless of valence. Finally, we assessed learning signals (unsigned prediction errors) that may underpin the acquisition of salience. Particularly the insula appears to be central for this function, encoding a subjective salience prediction error, similarly at the time of positively and negatively valenced outcomes. However, it appears to employ domain-specific time constants, leading to stronger salience signals in the aversive than the appetitive domain at the time of cues. These findings explain why previous research associated the insula with both valence-independent salience processing and with preferential encoding of the aversive domain. More generally, the distinction of value and salience appears to provide a useful framework for capturing the neural basis of motivated behavior.

SeminarNeuroscience

Metabolic-functional coupling of parvalbmunin-positive GABAergic interneurons in the injured and epileptic brain

Chris Dulla
Tufts
Jun 19, 2024

Parvalbumin-positive GABAergic interneurons (PV-INs) provide inhibitory control of excitatory neuron activity, coordinate circuit function, and regulate behavior and cognition. PV-INs are uniquely susceptible to loss and dysfunction in traumatic brain injury (TBI) and epilepsy but the cause of this susceptibility is unknown. One hypothesis is that PV-INs use specialized metabolic systems to support their high-frequency action potential firing and that metabolic stress disrupts these systems, leading to their dysfunction and loss. Metabolism-based therapies can restore PV-IN function after injury in preclinical TBI models. Based on these findings, we hypothesize that (1) PV-INs are highly metabolically specialized, (2) these specializations are lost after TBI, and (3) restoring PV-IN metabolic specializations can improve PV-IN function as well as TBI-related outcomes. Using novel single-cell approaches, we can now quantify cell-type-specific metabolism in complex tissues to determine whether PV-IN metabolic dysfunction contributes to the pathophysiology of TBI.

SeminarNeuroscience

The multi-phase plasticity supporting winner effect

Dayu Lin
NYU Neuroscience Institute, New York, USA
May 15, 2024

Aggression is an innate behavior across animal species. It is essential for competing for food, defending territory, securing mates, and protecting families and oneself. Since initiating an attack requires no explicit learning, the neural circuit underlying aggression is believed to be genetically and developmentally hardwired. Despite being innate, aggression is highly plastic. It is influenced by a wide variety of experiences, particularly winning and losing previous encounters. Numerous studies have shown that winning leads to an increased tendency to fight while losing leads to flight in future encounters. In the talk, I will present our recent findings regarding the neural mechanisms underlying the behavioral changes caused by winning.

SeminarNeuroscience

Modeling human brain development and disease: the role of primary cilia

Kyrousi Christina
Medical School, National and Kapodistrian University of Athens, Athens, Greece
Apr 24, 2024

Neurodevelopmental disorders (NDDs) impose a global burden, affecting an increasing number of individuals. While some causative genes have been identified, understanding the human-specific mechanisms involved in these disorders remains limited. Traditional gene-driven approaches for modeling brain diseases have failed to capture the diverse and convergent mechanisms at play. Centrosomes and cilia act as intermediaries between environmental and intrinsic signals, regulating cellular behavior. Mutations or dosage variations disrupting their function have been linked to brain formation deficits, highlighting their importance, yet their precise contributions remain largely unknown. Hence, we aim to investigate whether the centrosome/cilia axis is crucial for brain development and serves as a hub for human-specific mechanisms disrupted in NDDs. Towards this direction, we first demonstrated species-specific and cell-type-specific differences in the cilia-genes expression during mouse and human corticogenesis. Then, to dissect their role, we provoked their ectopic overexpression or silencing in the developing mouse cortex or in human brain organoids. Our findings suggest that cilia genes manipulation alters both the numbers and the position of NPCs and neurons in the developing cortex. Interestingly, primary cilium morphology is disrupted, as we find changes in their length, orientation and number that lead to disruption of the apical belt and altered delamination profiles during development. Our results give insight into the role of primary cilia in human cortical development and address fundamental questions regarding the diversity and convergence of gene function in development and disease manifestation. It has the potential to uncover novel pharmacological targets, facilitate personalized medicine, and improve the lives of individuals affected by NDDs through targeted cilia-based therapies.

SeminarNeuroscienceRecording

This decision matters: Sorting out the variables that lead to a single choice

Mathew Diamond
International School for Advanced Studies (SISSA)
Apr 18, 2024
SeminarNeuroscience

The quest for brain identification

Enrico Amico
Aston University
Mar 21, 2024

In the 17th century, physician Marcello Malpighi observed the existence of distinctive patterns of ridges and sweat glands on fingertips. This was a major breakthrough, and originated a long and continuing quest for ways to uniquely identify individuals based on fingerprints, a technique massively used until today. It is only in the past few years that technologies and methodologies have achieved high-quality measures of an individual’s brain to the extent that personality traits and behavior can be characterized. The concept of “fingerprints of the brain” is very novel and has been boosted thanks to a seminal publication by Finn et al. in 2015. They were among the firsts to show that an individual’s functional brain connectivity profile is both unique and reliable, similarly to a fingerprint, and that it is possible to identify an individual among a large group of subjects solely on the basis of her or his connectivity profile. Yet, the discovery of brain fingerprints opened up a plethora of new questions. In particular, what exactly is the information encoded in brain connectivity patterns that ultimately leads to correctly differentiating someone’s connectome from anybody else’s? In other words, what makes our brains unique? In this talk I am going to partially address these open questions while keeping a personal viewpoint on the subject. I will outline the main findings, discuss potential issues, and propose future directions in the quest for identifiability of human brain networks.

SeminarNeuroscienceRecording

Blood-brain barrier dysfunction in epilepsy: Time for translation

Alon Friedman
Dalhousie University
Feb 28, 2024

The neurovascular unit (NVU) consists of cerebral blood vessels, neurons, astrocytes, microglia, and pericytes. It plays a vital role in regulating blood flow and ensuring the proper functioning of neural circuits. Among other, this is made possible by the blood-brain barrier (BBB), which acts as both a physical and functional barrier. Previous studies have shown that dysfunction of the BBB is common in most neurological disorders and is associated with neural dysfunction. Our studies have demonstrated that BBB dysfunction results in the transformation of astrocytes through transforming growth factor beta (TGFβ) signaling. This leads to activation of the innate neuroinflammatory system, changes in the extracellular matrix, and pathological plasticity. These changes ultimately result in dysfunction of the cortical circuit, lower seizure threshold, and spontaneous seizures. Blocking TGFβ signaling and its associated pro-inflammatory pathway can prevent this cascade of events, reduces neuroinflammation, repairs BBB dysfunction, and prevents post-injury epilepsy, as shown in experimental rodents. To further understand and assess BBB integrity in human epilepsy, we developed a novel imaging technique that quantitatively measures BBB permeability. Our findings have confirmed that BBB dysfunction is common in patients with drug-resistant epilepsy and can assist in identifying the ictal-onset zone prior to surgery. Current clinical studies are ongoing to explore the potential of targeting BBB dysfunction as a novel treatment approach and investigate its role in drug resistance, the spread of seizures, and comorbidities associated with epilepsy.

SeminarNeuroscience

Trends in NeuroAI - Unified Scalable Neural Decoding (POYO)

Mehdi Azabou
Feb 22, 2024

Lead author Mehdi Azabou will present on his work "POYO-1: A Unified, Scalable Framework for Neural Population Decoding" (https://poyo-brain.github.io/). Mehdi is an ML PhD student at Georgia Tech advised by Dr. Eva Dyer. Paper link: https://arxiv.org/abs/2310.16046 Trends in NeuroAI is a reading group hosted by the MedARC Neuroimaging & AI lab (https://medarc.ai/fmri | https://groups.google.com/g/medarc-fmri).

SeminarNeuroscienceRecording

Imaging the subcortex; Microstructural and connectivity correlates of outcome variability in functional neurosurgery for movement disorders

Birte Forstmann, PhD & Francisca Ferreira, PhD
University of Amsterdam, Netherlands / University College London, UK
Dec 14, 2023

We are very much looking forward to host Francisca Ferreira and Birte Forstmann on December 14th, 2023, at noon ET / 6PM CET. Francisca Ferreira is a PhD student and Neurosurgery trainee at the University College of London Queen Square Institute of Neurology and a Royal College of Surgeons “Emerging Leaders” program laureate. Her presentation title will be: “Microstructural and connectivity correlates of outcome variability in functional neurosurgery for movement disorders”. Birte Forstmann, PhD, is the Director of the Amsterdam Brain and Cognition Center, a Professor of Cognitive Neuroscience at the University of Amsterdam, and a Professor by Special Appointment of Neuroscientific Testing of Psychological Models at the University of Leiden. Besides her scientific presentation (“Imaging the human subcortex”), she will give us a glimpse at the “Person behind the science”. You can register via talks.stimulatingbrains.org to receive the (free) Zoom link!

SeminarNeuroscience

Connectome-based models of neurodegenerative disease

Jacob Vogel
Lund University
Dec 6, 2023

Neurodegenerative diseases involve accumulation of aberrant proteins in the brain, leading to brain damage and progressive cognitive and behavioral dysfunction. Many gaps exist in our understanding of how these diseases initiate and how they progress through the brain. However, evidence has accumulated supporting the hypothesis that aberrant proteins can be transported using the brain’s intrinsic network architecture — in other words, using the brain’s natural communication pathways. This theory forms the basis of connectome-based computational models, which combine real human data and theoretical disease mechanisms to simulate the progression of neurodegenerative diseases through the brain. In this talk, I will first review work leading to the development of connectome-based models, and work from my lab and others that have used these models to test hypothetical modes of disease progression. Second, I will discuss the future and potential of connectome-based models to achieve clinically useful individual-level predictions, as well as to generate novel biological insights into disease progression. Along the way, I will highlight recent work by my lab and others that is already moving the needle toward these lofty goals.

SeminarNeuroscience

Movements and engagement during decision-making

Anne Churchland
University of California Los Angeles, USA
Nov 8, 2023

When experts are immersed in a task, a natural assumption is that their brains prioritize task-related activity. Accordingly, most efforts to understand neural activity during well-learned tasks focus on cognitive computations and task-related movements. Surprisingly, we observed that during decision-making, the cortex-wide activity of multiple cell types is dominated by movements, especially “uninstructed movements”, that are spontaneously expressed. These observations argue that animals execute expert decisions while performing richly varied, uninstructed movements that profoundly shape neural activity. To understand the relationship between these movements and decision-making, we examined the movements more closely. We tested whether the magnitude or the timing of the movements was correlated with decision-making performance. To do this, we partitioned movements into two groups: task-aligned movements that were well predicted by task events (such as the onset of the sensory stimulus or choice) and task independent movement (TIM) that occurred independently of task events. TIM had a reliable, inverse correlation with performance in head-restrained mice and freely moving rats. This hinted that the timing of spontaneous movements could indicate periods of disengagement. To confirm this, we compared TIM to the latent behavioral states recovered by a hidden Markov model with Bernoulli generalized linear model observations (GLM-HMM) and found these, again, to be inversely correlated. Finally, we examined the impact of these behavioral states on neural activity. Surprisingly, we found that the same movement impacts neural activity more strongly when animals are disengaged. An intriguing possibility is that these larger movement signals disrupt cognitive computations, leading to poor decision-making performance. Taken together, these observations argue that movements and cognitionare closely intertwined, even during expert decision-making.

SeminarNeuroscienceRecording

Neuroinflammation in Epilepsy: what have we learned from human brain tissue specimens ?

Eleonora Aronica
Amsterdam UMC
Oct 25, 2023

Epileptogenesis is a gradual and dynamic process leading to difficult-to-treat seizures. Several cellular, molecular, and pathophysiologic mechanisms, including the activation of inflammatory processes.  The use of human brain tissue represents a crucial strategy to advance our understanding of the underlying neuropathology and the molecular and cellular basis of epilepsy and related cognitive and behavioral comorbidities,  The mounting evidence obtained during the past decade has emphasized the critical role of inflammation  in the pathophysiological processes implicated in a large spectrum of genetic and acquired forms of  focal epilepsies. Dissecting the cellular and molecular mediators of  the pathological immune responses and their convergent and divergent mechanisms, is a major requisite for delineating their role in the establishment of epileptogenic networks. The role of small regulatory molecules involved in the regulation of  specific pro- and anti-inflammatory pathways  and the crosstalk between neuroinflammation and oxidative stress will be addressed.    The observations supporting the activation of both innate and adaptive immune responses in human focal epilepsy will be discussed and elaborated, highlighting specific inflammatory pathways as potential targets for antiepileptic, disease-modifying therapeutic strategies.

SeminarNeuroscience

BrainLM Journal Club

Connor Lane
Sep 29, 2023

Connor Lane will lead a journal club on the recent BrainLM preprint, a foundation model for fMRI trained using self-supervised masked autoencoder training. Preprint: https://www.biorxiv.org/content/10.1101/2023.09.12.557460v1 Tweeprint: https://twitter.com/david_van_dijk/status/1702336882301112631?t=Q2-U92-BpJUBh9C35iUbUA&s=19

SeminarNeuroscience

Sex hormone regulation of neural gene expression

Jessika Tollkuhn
Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
Sep 12, 2023

Gonadal steroid hormones are the principal drivers of sex-variable biology in vertebrates. In the brain, estrogen (17β-estradiol) establishes neural sex differences in many species and modulates mood, behavior, and energy balance in adulthood. To understand the diverse effects of estradiol on the brain, we profiled the genomic binding of estrogen receptor alpha (ERα), providing the first picture of the neural actions of any gonadal hormone receptor. To relate ERα target genes to brain sex differences we assessed gene expression and chromatin accessibility in the posterior bed nucleus of the stria terminalis (BNSTp), a sexually dimorphic node in limbic circuitry that underlies sex-differential social behaviors such as aggression and parenting. In adult animals we observe that levels of ERα are predictive of the extent of sex-variable gene expression, and that these sex differences are a dynamic readout of acute hormonal state. In neonates we find that transient ERα recruitment at birth leads to persistent chromatin opening and male-biased gene expression, demonstrating a true epigenetic mechanism for brain sexual differentiation. Collectively, our findings demonstrate that sex differences in gene expression in the brain are a readout of state-dependent hormone receptor actions, rather than other factors such as sex chromosomes. We anticipate that the ERα targets we have found will contribute to established sex differences in the incidence and etiology of neurological and psychiatric disorders.

SeminarNeuroscience

From pecking order to ketamine - neural mechanism of social and emotional behavior

Hailan Hu
Zhejiang University School of Medicine, Hangzhou, China
Jun 22, 2023

Emotions and social interactions color our lives and shape our behaviors. Using animal models and engineered manipulations, we aim to understand how social and emotional behaviors are encoded in the brain, focusing on the neural circuits underlying dominance hierarchy and depression. This lecture will highlight our recent discoveries on how downward social mobility leads to depression; how ketamine tames depression by blocking burst firing in the brain’s antireward center; and, how glia-neuron interaction plays a surprising role in this process. I will also present our recent work on the mechanism underlying the sustained antidepressant activity of ketamine and its brain region specificity. With these results, we hope to illuminate on a more unified theory on ketamine’s mode of action and inspire new treatment strategies for depression.

SeminarNeuroscience

From pecking order to ketamine - neural mechanism of social and emotional behavior

Hailan Hu
Zhejiang University School of Medicine, Hangzhou, China
Jun 21, 2023

Emotions and social interactions color our lives and shape our behaviors. Using animal models and engineered manipulations, we aim to understand how social and emotional behaviors are encoded in the brain, focusing on the neural circuits underlying dominance hierarchy and depression. This lecture will highlight our recent discoveries on how downward social mobility leads to depression; how ketamine tames depression by blocking burst firing in the brain’s antireward center; and, how glia-neuron interaction plays a surprising role in this process. I will also present our recent work on the mechanism underlying the sustained antidepressant activity of ketamine and its brain region specificity. With these results, we hope to illuminate on a more unified theory on ketamine’s mode of action and inspire new treatment strategies for depression.

SeminarNeuroscienceRecording

Consciousness in the age of mechanical minds

Robert Pepperell
Cardiff Metropolitan University
Jun 1, 2023

We are now clearly entering a new age in our relationship with machines. The power of AI natural language processors and image generators has rapidly exceeded the expectations of even those who developed them. Serious questions are now being asked about the extent to which machines could become — or perhaps already are — sentient or conscious. Do AI machines understand the instructions they are given and the answers they provide? In this talk I will consider the prospects for conscious machines, by which I mean machines that have feelings, know about their own existence, and about ours. I will suggest that the recent focus on information processing in models of consciousness, in which the brain is treated as a kind of digital computer, have mislead us about the nature of consciousness and how it is produced in biological systems. Treating the brain as an energy processing system is more likely to yield answers to these fundamental questions and help us understand how and when machines might become minds.

SeminarNeuroscienceRecording

Immunosuppression for Parkinson's disease - a new therapeutic strategy?

Caroline Williams-Gray
Department of Clinical Neurosciences, University of Cambridge
May 30, 2023

Caroline Williams-Gray is a Principal Research Associate in the Department of Clinical Neurosciences, University of Cambridge, and an honorary consultant neurologist specializing in Parkinson’s disease and movement disorders. She leads a translational research group investigating the clinical and biological heterogeneity of PD, with the ultimate goal of developing more targeted therapies for different Parkinson’s subtypes. Her recent work has focused on the theory that the immune system plays a significant role in mediating the heterogeneity of PD and its progression. Her lab is investigating this using blood and CSF -based immune markers, PET neuroimaging and neuropathology in stratified PD cohorts; and she is leading the first randomized controlled trial repurposing a peripheral immunosuppressive drug (azathioprine) to slow the progression of PD.

SeminarNeuroscience

The Picower Institute Spring 2023 Symposium "Environmental and Social Determinants of Child Mental Health

Cecile Richards (Keynote - fmr President of Planned Parenthood), Gregory Bratman, PhD, Annie Belcourt, PhD, Paul Dworkin, MD, Byungkook Lim, PhD, Sarah Milligan-Toffler, Catherine Jensen Peña, PhD, Ravi Raju, MD. PhD, Robert Sege, MD, PhD, Marc Weisskopf, PhD, ScD, Nsedu Obot Witherspoon, MPH
May 11, 2023

Studies show that abuse, neglect or trauma during childhood can lead to lifelong struggles including with mental health. Fortunately research also indicates that solutions and interventions at various stages of life can be developed to help. But even among people who remain resilient or do not experience acute stresses, a lack of opportunity early in life due to poverty or systemic racism can still constrain their ability to realize their full potential. In what ways are health and other outcomes affected by early life difficulty? What can individuals and institutions do to enhance opportunity?" "This daylong event will feature talks by neuroscientists, policy experts, physicians, educators and activists as they discuss how our experiences and biology work together to affect how our minds develop and what can be accomplished in helping people overcome early disadvantages.

SeminarNeuroscience

Euclidean coordinates are the wrong prior for primate vision

Gary Cottrell
University of California, San Diego (UCSD)
May 10, 2023

The mapping from the visual field to V1 can be approximated by a log-polar transform. In this domain, scale is a left-right shift, and rotation is an up-down shift. When fed into a standard shift-invariant convolutional network, this provides scale and rotation invariance. However, translation invariance is lost. In our model, this is compensated for by multiple fixations on an object. Due to the high concentration of cones in the fovea with the dropoff of resolution in the periphery, fully 10 degrees of visual angle take up about half of V1, with the remaining 170 degrees (or so) taking up the other half. This layout provides the basis for the central and peripheral pathways. Simulations with this model closely match human performance in scene classification, and competition between the pathways leads to the peripheral pathway being used for this task. Remarkably, in spite of the property of rotation invariance, this model can explain the inverted face effect. We suggest that the standard method of using image coordinates is the wrong prior for models of primate vision.

SeminarNeuroscience

Epigenetic rewiring in Schinzel-Giedion syndrome

Alessandro Sessa, PhD
San Raffaele Scientific Institute, Milan (Italy), Stem Cell & Neurogenesis Unit
May 3, 2023

During life, a variety of specialized cells arise to grant the right and timely corrected functions of tissues and organs. Regulation of chromatin in defining specialized genomic regions (e.g. enhancers) plays a key role in developmental transitions from progenitors into cell lineages. These enhancers, properly topologically positioned in 3D space, ultimately guide the transcriptional programs. It is becoming clear that several pathologies converge in differential enhancer usage with respect to physiological situations. However, why some regulatory regions are physiologically preferred, while some others can emerge in certain conditions, including other fate decisions or diseases, remains obscure. Schinzel-Giedion syndrome (SGS) is a rare disease with symptoms such as severe developmental delay, congenital malformations, progressive brain atrophy, intractable seizures, and infantile death. SGS is caused by mutations in the SETBP1 gene that results in its accumulation further leading to the downstream accumulation of SET. The oncoprotein SET has been found as part of the histone chaperone complex INHAT that blocks the activity of histone acetyltransferases suggesting that SGS may (i) represent a natural model of alternative chromatin regulation and (ii) offer chances to study downstream (mal)adaptive mechanisms. I will present our work on the characterization of SGS in appropriate experimental models including iPSC-derived cultures and mouse.

SeminarNeuroscience

Off-policy learning in the basal ganglia

Ashok Litwin-Kumar
Columbia University, New York
May 3, 2023

I will discuss work with Jack Lindsey modeling reinforcement learning for action selection in the basal ganglia. I will argue that the presence of multiple brain regions, in addition to the basal ganglia, that contribute to motor control motivates the need for an off-policy basal ganglia learning algorithm. I will then describe a biological implementation of such an algorithm that predicts tuning of dopamine neurons to a quantity we call "action surprise," in addition to reward prediction error. In the same model, an implementation of learning from a motor efference copy also predicts a novel solution to the problem of multiplexing feedforward and efference-related striatal activity. The solution exploits the difference between D1 and D2-expressing medium spiny neurons and leads to predictions about striatal dynamics.

SeminarNeuroscienceRecording

Why is 7T MRI indispensable in epilepsy now?

Maxime Guye
CRMBM Aix Marseille University
Apr 26, 2023

Identifying a structural brain lesion on MRI is the most important factor that correlates with seizure freedom after surgery in patients suffering from drug-resistant focal epilepsy. By providing better image contrast and higher spatial resolution, structural MRI at 7 Tesla (7T) can lead to lesion detection in about 25% of patients presenting with negative MRI at lower fields. In addition to a better detection/delineation/phenotyping of epileptogenic lesions, higher signal at ultra-high field also facilitates more detailed analyses of several functional and molecular alterations of tissues, susceptible to detect epileptogenic properties even in absence of visible lesions. These advantages but also the technical challenges of 7T MRI in practice will be presented and discussed.

SeminarNeuroscience

Obesity and Brain – Bidirectional Influences

Alain Dagher
McGill University
Apr 11, 2023

The regulation of body weight relies on homeostatic mechanisms that use a combination of internal signals and external cues to initiate and terminate food intake. Homeostasis depends on intricate communication between the body and the hypothalamus involving numerous neural and hormonal signals. However, there is growing evidence that higher-level cognitive function may also influence energy balance. For instance, research has shown that BMI is consistently linked to various brain, cognitive, and personality measures, implicating executive, reward, and attentional systems. Moreover, the rise in obesity rates over the past half-century is attributed to the affordability and widespread availability of highly processed foods, a phenomenon that contradicts the idea that food intake is solely regulated by homeostasis. I will suggest that prefrontal systems involved in value computation and motivation act to limit food overconsumption when food is scarce or expensive, but promote over-eating when food is abundant, an optimum strategy from an economic standpoint. I will review the genetic and neuroscience literature on the CNS control of body weight. I will present recent studies supporting a role of prefrontal systems in weight control. I will also present contradictory evidence showing that frontal executive and cognitive findings in obesity may be a consequence not a cause of increased hunger. Finally I will review the effects of obesity on brain anatomy and function. Chronic adiposity leads to cerebrovascular dysfunction, cortical thinning, and cognitive impairment. As the most common preventable risk factor for dementia, obesity poses a significant threat to brain health. I will conclude by reviewing evidence for treatment of obesity in adults to prevent brain disease.

SeminarNeuroscienceRecording

The smart image compression algorithm in the retina: a theoretical study of recoding inputs in neural circuits

Gabrielle Gutierrez
Columbia University, New York
Apr 5, 2023

Computation in neural circuits relies on a common set of motifs, including divergence of common inputs to parallel pathways, convergence of multiple inputs to a single neuron, and nonlinearities that select some signals over others. Convergence and circuit nonlinearities, considered individually, can lead to a loss of information about the inputs. Past work has detailed how to optimize nonlinearities and circuit weights to maximize information, but we show that selective nonlinearities, acting together with divergent and convergent circuit structure, can improve information transmission over a purely linear circuit despite the suboptimality of these components individually. These nonlinearities recode the inputs in a manner that preserves the variance among converged inputs. Our results suggest that neural circuits may be doing better than expected without finely tuned weights.

SeminarNeuroscience

Integration of 3D human stem cell models derived from post-mortem tissue and statistical genomics to guide schizophrenia therapeutic development

Jennifer Erwin, Ph.D
Lieber Institute for Brain Development; Department of Neurology and Neuroscience; Johns Hopkins University School of Medicine
Mar 15, 2023

Schizophrenia is a neuropsychiatric disorder characterized by positive symptoms (such as hallucinations and delusions), negative symptoms (such as avolition and withdrawal) and cognitive dysfunction1. Schizophrenia is highly heritable, and genetic studies are playing a pivotal role in identifying potential biomarkers and causal disease mechanisms with the hope of informing new treatments. Genome-wide association studies (GWAS) identified nearly 270 loci with a high statistical association with schizophrenia risk; however each locus confers only a small increase in risk therefore it is difficult to translate these findings into understanding disease biology that can lead to treatments. Induced pluripotent stem cell (iPSC) models are a tractable system to translate genetic findings and interrogate mechanisms of pathogenesis. Mounting research with patient-derived iPSCs has proposed several neurodevelopmental pathways altered in SCZ, such as neural progenitor cell (NPC) proliferation, imbalanced differentiation of excitatory and inhibitory cortical neurons. However, it is unclear what exactly these iPS models recapitulate, how potential perturbations of early brain development translates into illness in adults and how iPS models that represent fetal stages can be utilized to further drug development efforts to treat adult illness. I will present the largest transcriptome analysis of post-mortem caudate nucleus in schizophrenia where we discovered that decreased presynaptic DRD2 autoregulation is the causal dopamine risk factor for schizophrenia (Benjamin et al, Nature Neuroscience 2022 https://doi.org/10.1038/s41593-022-01182-7). We developed stem cell models from a subset of the postmortem cohort to better understand the molecular underpinnings of human psychiatric disorders (Sawada et al, Stem Cell Research 2020). We established a method for the differentiation of iPS cells into ventral forebrain organoids and performed single cell RNAseq and cellular phenotyping. To our knowledge, this is the first study to evaluate iPSC models of SZ from the same individuals with postmortem tissue. Our study establishes that striatal neurons in the patients with SCZ carry abnormalities that originated during early brain development. Differentiation of inhibitory neurons is accelerated whereas excitatory neuronal development is delayed, implicating an excitation and inhibition (E-I) imbalance during early brain development in SCZ. We found a significant overlap of genes upregulated in the inhibitory neurons in SCZ organoids with upregulated genes in postmortem caudate tissues from patients with SCZ compared with control individuals, including the donors of our iPS cell cohort. Altogether, we demonstrate that ventral forebrain organoids derived from postmortem tissue of individuals with schizophrenia recapitulate perturbed striatal gene expression dynamics of the donors’ brains (Sawada et al, biorxiv 2022 https://doi.org/10.1101/2022.05.26.493589).

SeminarNeuroscienceRecording

Prox2+ and Runx3+ vagal sensory neurons regulate esophageal motility

Elijah Lowenstein
Birchmeier lab, Max Delbrück Center
Mar 1, 2023

Sensory neurons of the vagus nerve monitor distention and stretch in the gastrointestinal tract. We used genetically guided anatomical tracing, optogenetics and electrophysiology to identify and characterize two vagal sensory neuronal subtypes expressing Prox2 and Runx3. We show that these neuronal subtypes innervate the esophagus where they display regionalized innervation patterns. Electrophysiological analyses showed that they are both low threshold mechanoreceptors but possess different adaptation properties. Lastly, genetic ablation of Prox2 and Runx3 neurons demonstrated their essential roles for esophageal peristalsis and swallowing in freely behaving animals. Our work reveals the identity and function of the vagal neurons that provide mechanosensory feedback from the esophagus to the brain and could lead to better understanding and treatment of esophageal motility disorders.

SeminarNeuroscienceRecording

25 years of DBS beyond movement disorders: what challenges are we facing?; Directional DBS targeting of different nuclei in the thalamus for the treatment of pain

Veerle Visser-Vandewalle, MD, PhD & Marie Krüger, MD
University Hospital Cologne, Germany / Kantonsspital St. Gallen, Switzerland & UCL / Queensquare London, UK
Feb 23, 2023

On Thursday, 23rd of February, we will host Veerle Visser-Vandewalle and Marie Krüger. Marie Krüger, MD, is is currently leading the stereotactic surgery unit in St. Gallen but is on her move to join the team at UCL / Queensquare London. She will discuss “Directional DBS targeting of different nuclei in the thalamus for the treatment of pain”. Veerle Visser-Vandewalle, MD, PhD, is the Head of the Department of Stereotactic and Functional Neurosurgery at University Hospital of Cologne. Beside his scientific presentation on “25 years of DBS beyond movement disorders: what challenges are we facing?”, she will also give us a glimpse at the “Person behind the science”. The talks will be followed by a shared discussion. You can register via talks.stimulatingbrains.org to receive the (free) Zoom link!

SeminarNeuroscience

Myelin Formation and Oligodendrocyte Biology in Epilepsy

Angelika Mühlebner
Universitair Medisch Centrum Utrecht
Feb 16, 2023

Epilepsy is one of the most common neurological diseases according to the World Health Organization (WHO) affecting around 70 million people worldwide [WHO]. Patients who suffer from epilepsy also suffer from a variety of neuro-psychiatric co-morbidities, which they can experience as crippling as the seizure condition itself. Adequate organization of cerebral white matter is utterly important for cognitive development. The failure of integration of neurologic function with cognition is reflected in neuro-psychiatric disease, such as autism spectrum disorder (ASD). However, in epilepsy we know little about the importance of white matter abnormalities in epilepsy-associated co-morbidities. Epilepsy surgery is an important therapy strategy in patients where conventional anti-epileptic drug treatment fails . On histology of the resected brain samples, malformations of cortical development (MCD) are common among the epilepsy surgery population, especially focal cortical dysplasia (FCD) and tuberous sclerosis complex (TSC). Both pathologies are associated with constitutive activation of the mTOR pathway. Interestingly, some type of FCD is morphological similar to TSC cortical tubers including the abnormalities of the white matter. Hypomyelination with lack of myelin-producing cells, the oligodendrocytes, within the lesional area is a striking phenomenon. Impairment of the complex myelination process can have a major impact on brain function. In the worst case leading to distorted or interrupted neurotransmissions. It is still unclear whether the observed myelin pathology in epilepsy surgical specimens is primarily related to the underlying malformation process or is just a secondary phenomenon of recurrent epileptic seizures creating a toxic micro-environment which hampers myelin formation. Interestingly, mTORC1 has been implicated as key signal for myelination, thus, promoting the maturation of oligodendrocytes . These results, however, remain controversial. Regardless of the underlying pathophysiologic mechanism, alterations of myelin dynamics, depending on their severity, are known to be linked to various kinds of developmental disorders or neuropsychiatric manifestations.

SeminarNeuroscienceRecording

Brain mosaicism in epileptogenic cortical malformations

Stéphanie Baulac
ICM Paris
Feb 1, 2023

Focal Cortical Dysplasia (FCD) is the most common focal cortical malformation leading to intractable childhood focal epilepsy. In recent years, we and others have shown that FCD type II is caused by mosaic mutations in genes within the PI3K-AKT-mTOR-signaling pathway. Hyperactivation of the mTOR pathway accounts for neuropathological abnormalities and seizure occurrence in FCD. We further showed from human surgical FCDII tissue that epileptiform activity correlates with the density of mutated dysmorphic neurons, supporting their pro-epileptogenic role. The level of mosaicism, as defined by variant allele frequency (VAF) is thought to correlate with the size and regional brain distribution of the lesion such that when a somatic mutation occurs early during the cortical development, the dysplastic area is smaller than if it occurs later. Novel approaches based on the detection of cell-free DNA from the CSF and from trace tissue adherent to SEEG electrodes promise future opportunities for genetic testing during the presurgical evaluation of refractory epilepsy patients or in those that are not eligible for surgery. In utero-based electroporation mouse models allow to express somatic mutation during neurodevelopment and recapitulate most neuropathological and clinical features of FCDII, establishing relevant preclinical mouse models for developing precision medicine strategies.

SeminarNeuroscienceRecording

Hippocampal network dynamics during impaired working memory in epileptic mice

Maryam Pasdarnavab
Ewell lab, University of Bonn
Feb 1, 2023

Memory impairment is a common cognitive deficit in temporal lobe epilepsy (TLE). The hippocampus is severely altered in TLE exhibiting multiple anatomical changes that lead to a hyperexcitable network capable of generating frequent epileptic discharges and seizures. In this study we investigated whether hippocampal involvement in epileptic activity drives working memory deficits using bilateral LFP recordings from CA1 during task performance. We discovered that epileptic mice experienced focal rhythmic discharges (FRDs) while they performed the spatial working memory task. Spatial correlation analysis revealed that FRDs were often spatially stable on the maze and were most common around reward zones (25 ‰) and delay zones (50 ‰). Memory performance was correlated with stability of FRDs, suggesting that spatially unstable FRDs interfere with working memory codes in real time.

SeminarNeuroscience

LifePerceives

Michael Levin, Katie Bentley, Anil Seth, Lucia Pietroiusti, Andrew Adamatzky, and many more..
Jan 20, 2023

Life Perceives is a symposium bringing together scientists and artists for an open exploration of how “perception” can be understood as a phenomenon that does not only belong to humans, or even the so-called “higher organisms”, but exists across the entire spectrum of life in a myriad of forms. The symposium invites leading practitioners from the arts and sciences to present unique insights through short talks, open discussions, and artistic interventions that bring us slightly closer to the life worlds of plants and fungi, microbial communities and immune systems, cuttlefish and crows. What do we mean when we talk about perception in other species? Do other organisms have an experience of the world? Or does our human-centred perspective make understanding other forms of life on their own terms an impossible dream? Whatever your answers to these questions may be, we hope to unsettle them, and leave you more curious than when you arrived.

SeminarNeuroscienceRecording

Cortical seizure mechanisms: insights from calcium, glutamate and GABA imaging

Dimitri Kullmann
University College London
Jan 18, 2023

Focal neocortical epilepsy is associated with intermittent brief population discharges (interictal spikes), which resemble sentinel spikes that often occur at the onset of seizures. Why interictal spikes self-terminate whilst seizures persist and propagate is incompletely understood, but is likely to relate to the intermittent collapse of feed-forward GABAergic inhibition. Inhibition could fail through multiple mechanisms, including (i) an attenuation or even reversal of the driving force for chloride in postsynaptic neurons because of intense activation of GABAA receptors, (ii) an elevation of potassium secondary to chloride influx leading to depolarization of neurons, or (iii) insufficient GABA release from interneurons. I shall describe the results of experiments using fluorescence imaging of calcium, glutamate or GABA in awake rodent models of neocortical epileptiform activity. Interictal spikes were accompanied by brief glutamate transients which were maximal at the initiation site and rapidly propagatedcentrifugally. GABA transients lasted longer than glutamate transients and were maximal ~1.5 mm from the focus. Prior to seizure initiation GABA transients were attenuated, whilst glutamate transients increased, consistent with a progressive failure of local inhibitory restraint. As seizures increased in frequency, there was a gradual increase in the spatial extent of spike-associated glutamate transients associated with interictal spikes. Neurotransmitter imaging thus reveals a progressive collapse of an annulus of feed-forward GABA release, allowing runaway recruitment of excitatory neurons as a fundamental mechanism underlying the escape of seizures from local inhibitory restraint.

SeminarNeuroscienceRecording

Protective microglial signaling in Alzheimer's Disease

Hannah Ennerfelt
Stanford University
Dec 16, 2022

Recent studies have begun to reveal critical roles for the brain’s professional phagocytes, microglia, and their receptors in the control of neurotoxic amyloid beta (Aβ) and myelin debris accumulation in neurodegenerative disease. However, the critical intracellular molecules that orchestrate neuroprotective functions of microglia remain poorly understood. In our studies, we find that targeted deletion of SYK in microglia leads to exacerbated Aβ deposition, aggravated neuropathology, and cognitive defects in the 5xFAD mouse model of Alzheimer’s disease (AD). Disruption of SYK signaling in this AD model was further shown to impede the development of disease-associated microglia (DAM), alter AKT/GSK3β-signaling, and restrict Aβ phagocytosis by microglia. Conversely, receptor-mediated activation of SYK limits Aβ load. We also found that SYK critically regulates microglial phagocytosis and DAM acquisition in demyelinating disease. Collectively, these results broaden our understanding of the key innate immune signaling molecules that instruct beneficial microglial functions in response to neurotoxic material." https://doi.org/10.1016/j.cell.2022.09.030

SeminarNeuroscienceRecording

Analogies between exemplars of schema-governed categories

Ricardo Minervino
National University of Comahue
Dec 8, 2022

Dominant theories of analogical thinking postulate that making an analogy consists in discovering that two superficially different situations share isomorphic systems of similar relations. According to this perspective, the comparison between the two situations may eventually lead to the construction of a schema, which retains the structural aspects they share and deletes their specific contents. We have developed a new approach to analogical thinking, whose purpose is to explain a particular type of analogies: those in which the analogs are exemplars of a schema-governed category (e.g., two instances of robbery). As compared to standard analogies, these comparisons are noteworthy in that a well-established schema (the schema-governed category) mediates each one of the subprocesses involved in analogical thinking. We argue that the category assignment approach is able to provide a better account of how the analogical subprocesses of retrieval, mapping, re-representation, evaluation and inference generation are carried out during the processing of this specific kind of analogies. The arguments presented are accompanied by brief descriptions of some of the studies that provided support for this approach.

SeminarNeuroscienceRecording

Connecting performance benefits on visual tasks to neural mechanisms using convolutional neural networks

Grace Lindsay
New York University (NYU)
Dec 7, 2022

Behavioral studies have demonstrated that certain task features reliably enhance classification performance for challenging visual stimuli. These include extended image presentation time and the valid cueing of attention. Here, I will show how convolutional neural networks can be used as a model of the visual system that connects neural activity changes with such performance changes. Specifically, I will discuss how different anatomical forms of recurrence can account for better classification of noisy and degraded images with extended processing time. I will then show how experimentally-observed neural activity changes associated with feature attention lead to observed performance changes on detection tasks. I will also discuss the implications these results have for how we identify the neural mechanisms and architectures important for behavior.

SeminarNeuroscienceRecording

How can we shift research culture to drive Credibility in Neuroscience?

Multiple speakers
Dec 1, 2022

This webinar will demonstrate changes that are already happening at individual, institutional and funder level to shift research culture toward supporting credible research, and will allow attendees working in neuroscience to ask further questions to our speakers. Our panel of speakers, chaired by Ana Dorrego-Rivas: Emily Farran, Professor in Developmental Psychology and Academic Lead Research Culture and Integrity at the University of Surrey Rosa Sancho, Head of Research at Alzheimer's Research UK Sepideh Keshavarzi, Senior Research Fellow at the Sainsbury Wellcome Centre

SeminarNeuroscienceRecording

How can we treat visceral pain?

David Bulmer
Department of Pharmacology, University of Cambridge
Nov 29, 2022

Chronic pain is a leading cause of morbidity, common to patients with gastrointestinal diseases such as irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). Most pain killers are largely ineffective against this type of pain or restricted for use in these patients due to gut related complications and risk of addition. A significant unmet clinical need therefore exists to develop novel non-opioid based visceral analgesics.

SeminarNeuroscience

Taking the pulse of ageing: the role of cerebrovascular risk factors in ageing and dementia

Monica Fabiani
Beckman Institute for Advanced Science and Technology, University of Illinois
Nov 23, 2022

Cerebrovascular support is critical for healthy cognitive ageing. Reduced cerebral blood flow in ageing is caused, among other things, by hypertension, arteriosclerosis (i.e. stiffening of the arteries) and plaque formation. Arterial stiffness is predictive of cognitive decline, is a critical risk factor for cerebrovascular accidents, and has been linked to heightened risks for Alzheimer’s Disease and other forms of dementia. The elasticity of cerebral arteries is influenced by lifestyle factors, including cardiorespiratory fitness. Monica will discuss data obtained in their laboratory with new noninvasive measures of cerebrovascular health (pulse-DOT, a diffuse optical tomographic method for studying cerebral arteriosclerosis), in conjunction with structural and functional brain measures and cognitive assessments. These findings support a model in which localised changes in arteriosclerosis lead to specific profiles of structural, functional, and cognitive declines, paving a way to individualised interventions.

SeminarNeuroscienceRecording

Shallow networks run deep: How peripheral preprocessing facilitates odor classification

Yonatan Aljadeff
University of California, San Diego (UCSD)
Nov 9, 2022

Drosophila olfactory sensory hairs ("sensilla") typically house two olfactory receptor neurons (ORNs) which can laterally inhibit each other via electrical ("ephaptic") coupling. ORN pairing is highly stereotyped and genetically determined. Thus, olfactory signals arriving in the Antennal Lobe (AL) have been pre-processed by a fixed and shallow network at the periphery. To uncover the functional significance of this organization, we developed a nonlinear phenomenological model of asymmetrically coupled ORNs responding to odor mixture stimuli. We derived an analytical solution to the ORNs’ dynamics, which shows that the peripheral network can extract the valence of specific odor mixtures via transient amplification. Our model predicts that for efficient read-out of the amplified valence signal there must exist specific patterns of downstream connectivity that reflect the organization at the periphery. Analysis of AL→Lateral Horn (LH) fly connectomic data reveals evidence directly supporting this prediction. We further studied the effect of ephaptic coupling on olfactory processing in the AL→Mushroom Body (MB) pathway. We show that stereotyped ephaptic interactions between ORNs lead to a clustered odor representation of glomerular responses. Such clustering in the AL is an essential assumption of theoretical studies on odor recognition in the MB. Together our work shows that preprocessing of olfactory stimuli by a fixed and shallow network increases sensitivity to specific odor mixtures, and aids in the learning of novel olfactory stimuli. Work led by Palka Puri, in collaboration with Chih-Ying Su and Shiuan-Tze Wu.

SeminarNeuroscienceRecording

The role of population structure in computations through neural dynamics

Alexis Dubreuil
French National Centre for Scientific Research (CNRS), Bordeaux
Nov 2, 2022

Neural computations are currently investigated using two separate approaches: sorting neurons into functional subpopulations or examining the low-dimensional dynamics of collective activity. Whether and how these two aspects interact to shape computations is currently unclear. Using a novel approach to extract computational mechanisms from networks trained on neuroscience tasks, here we show that the dimensionality of the dynamics and subpopulation structure play fundamentally com- plementary roles. Although various tasks can be implemented by increasing the dimensionality in networks with fully random population structure, flexible input–output mappings instead require a non-random population structure that can be described in terms of multiple subpopulations. Our analyses revealed that such a subpopulation structure enables flexible computations through a mechanism based on gain-controlled modulations that flexibly shape the collective dynamics. Our results lead to task-specific predictions for the structure of neural selectivity, for inactivation experiments and for the implication of different neurons in multi-tasking.

SeminarNeuroscience

Myelin Formation and Oligodendrocyte Biology in Epilepsy

Angelika Mühlebner
Universitair Medisch Centrum Utrecht
Oct 19, 2022

Epilepsy is one of the most common neurological diseases according to the World Health Organization (WHO) affecting around 70 million people worldwide [WHO]. Patients who suffer from epilepsy also suffer from a variety of neuro-psychiatric co-morbidities, which they can experience as crippling as the seizure condition itself. Adequate organization of cerebral white matter is utterly important for cognitive development. The failure of integration of neurologic function with cognition is reflected in neuro-psychiatric disease, such as autism spectrum disorder (ASD). However, in epilepsy we know little about the importance of white matter abnormalities in epilepsy-associated co-morbidities. Epilepsy surgery is an important therapy strategy in patients where conventional anti-epileptic drug treatment fails . On histology of the resected brain samples, malformations of cortical development (MCD) are common among the epilepsy surgery population, especially focal cortical dysplasia (FCD) and tuberous sclerosis complex (TSC). Both pathologies are associated with constitutive activation of the mTOR pathway. Interestingly, some type of FCD is morphological similar to TSC cortical tubers including the abnormalities of the white matter. Hypomyelination with lack of myelin-producing cells, the oligodendrocytes, within the lesional area is a striking phenomenon. Impairment of the complex myelination process can have a major impact on brain function. In the worst case leading to distorted or interrupted neurotransmissions. It is still unclear whether the observed myelin pathology in epilepsy surgical specimens is primarily related to the underlying malformation process or is just a secondary phenomenon of recurrent epileptic seizures creating a toxic micro-environment which hampers myelin formation. Interestingly, mTORC1 has been implicated as key signal for myelination, thus, promoting the maturation of oligodendrocytes . These results, however, remain controversial. Regardless of the underlying pathophysiologic mechanism, alterations of myelin dynamics, depending on their severity, are known to be linked to various kinds of developmental disorders or neuropsychiatric manifestations.

SeminarNeuroscienceRecording

Designing the BEARS (Both Ears) Virtual Reality Training Package to Improve Spatial Hearing in Young People with Bilateral Cochlear Implant

Deborah Vickers
Clinical Neurosciences
Oct 11, 2022

Results: the main areas which were modified based on participatory feedback were the variety of immersive scenarios to cover a range of ages and interests, the number of levels of complexity to ensure small improvements were measured, the feedback and reward schemes to ensure positive reinforcement, and specific provision for participants with balance issues, who had difficulties when using head-mounted displays. The effectiveness of the finalised BEARS suite will be evaluated in a large-scale clinical trial. We have added in additional login options for other members of the family and based on patient feedback we have improved the accompanying reward schemes. Conclusions: Through participatory design we have developed a training package (BEARS) for young people with bilateral cochlear implants. The training games are appropriate for use by the study population and ultimately should lead to patients taking control of their own management and reducing the reliance upon outpatient-based rehabilitation programmes. Virtual reality training provides a more relevant and engaging approach to rehabilitation for young people.

SeminarNeuroscienceRecording

Time as its own representation? Exploring a link between timing of cognition and time perception

Ishan Singhal
Indian Institute of Technology, Kanpur
Sep 28, 2022

The way we represent and perceive time has crucial implications for studying temporality in conscious experience. Contrasting positions posit that temporal information is separately abstracted out like any other perceptual property, or that time is represented through representations having temporal properties themselves. To add to this debate, we investigated alterations in felt time in conditions where only conscious visual experience is altered while a bistable figure remains physically unchanged. In this talk, I will discuss two studies that we have done in relation to answering this question. In study 1, we investigated whether perceptual switches in fixed intervals altered felt time. In three experiments we showed that a break in visual experience (via a perceptual switch) also leads to a break in felt time. In study 2, we are currently looking at figure-ground perception in ambigous displays. Here, in experiment 1 we show that differences in flicker frequencies on ambigous regions can induce figure-ground segregation. To see if a reverse complementarity exists for felt time, we ask participants to view ambigous regions as figure/ground and show that they have different temporal resolutions for the same region based on whether it is seen as figure or background. Overall, the two studies provide evidence for temporal mirroring and isomorphism in visual experience, arguing for a link between the timing of experience and time perception.

ePosterNeuroscience

Elucidating the mechanisms leading to epilepsy in a Depdc5 mouse model

Laurene Layus, Alexandre Bacq, Charlotte Deleuze, Marion Doladilhe, Eric Le Guern, Stephanie Baulac
ePosterNeuroscience

Activation of parvalbumin+ interneurons in orbitofrontal cortex leads to higher functional connectivity, increased cerebral blood volume, and social dysregulation

Elmira Khatamsaz, Tudor M. Ionescu, Franziska Stoller, Katja Szkudlarek, Bastian Hengerer

FENS Forum 2024

ePosterNeuroscience

Chronic exposure to glucocorticoids during critical neurodevelopmental periods leads to lasting shifts in neuronal type distribution and overall brain architecture

Ilknur Safak Demirel, Pia Giraudet, Malgorzata Grochowicz, Anthi C. Krontira, Leander Dony, Tim Schäfer, Elisabeth Binder, Cristiana Cruceanu

FENS Forum 2024

ePosterNeuroscience

Abrogated RING1B function leads to perturbed neural stem cell and forebrain development

Lucy Doyle, Alexandra Derrien, Firuze Unlu Bektaş, Dipta Sengupta, Jennifer Lawson, Ian Adams, Robert S. Illingworth

FENS Forum 2024

ePosterNeuroscience

Force coupling leads to neural coordination via enviromental feedback

Claudius Gros, Elias Fischer, Bulcsu Sandor

Bernstein Conference 2024

ePosterNeuroscience

Perceptual adaptation leads to changes in encoding accuracy that match those of a recurrent neural network optimized to predict the future

Jiang Mao

Neuromatch 5

ePosterNeuroscience

Exceptionally large rewards lead to a collapse in neural information about upcoming movements

Adam Smoulder,Patrick Marino,Nicholas Pavlovsky,Emily Oby,Sam Snyder,William Bishop,Byron Yu,Steven Chase,Aaron Batista

COSYNE 2022

ePosterNeuroscience

Initialization choice leads to different solutions in trained RNNs

Friedrich Schuessler,Francesca Mastrogiuseppe,Srdjan Ostojic,Omri Barak

COSYNE 2022

ePosterNeuroscience

Initialization choice leads to different solutions in trained RNNs

Friedrich Schuessler,Francesca Mastrogiuseppe,Srdjan Ostojic,Omri Barak

COSYNE 2022

ePosterNeuroscience

Localized balance of excitation and inhibition leads to normalization

Yashar Ahmadian

COSYNE 2022

ePosterNeuroscience

Localized balance of excitation and inhibition leads to normalization

Yashar Ahmadian

COSYNE 2022

ePosterNeuroscience

Alterations in WWOX protein and gene lead to mitochondrial dysfunction in amyotrophic lateral sclerosis

Tiziana Petrozziello, Spencer E. Kim, Alexandra N. Mills, Sali M. Farhan, Jennie C. Roy, Nicholas C. Lorocco, Austin Birmingham, Khashayar Vakili, James D. Berry, James A. Walker, Ricardo Mouro-Pinto, Ghazaleh Sadri-Vakili
ePosterNeuroscience

Altered subcellular mechanisms and cell cycle in Eml1 mutant neuronal progenitors : primary events leading to a cortical malformation

Donia Zaidi, Kaviya Chinnappa, Berfu Nur Yiğit, Sergi Roig Puiggros, Ana Uzquiano, Esther Klingler, Nurhan Özlü, Denis Jabaudon, Fiona Francis
ePosterNeuroscience

Selection from working memory can lead to catastrophic misbinding errors

Matteo Alleman,Matthew F. Panichello,Timothy J. Buschman,W. Jeffrey Johnston

COSYNE 2022

ePosterNeuroscience

Selection from working memory can lead to catastrophic misbinding errors

Matteo Alleman,Matthew F. Panichello,Timothy J. Buschman,W. Jeffrey Johnston

COSYNE 2022

ePosterNeuroscience

Representational drift leads to sparse activity solutions that are robust to noise and learning

Maanasa Natrajan & James Fitzgerald

COSYNE 2023

ePosterNeuroscience

Multiple timescales lead to hierarchical decision-making strategies in brain-body models

Michele Nardin, Ann Hermundstad

COSYNE 2025

ePosterNeuroscience

Aberrant survival of Cajal-Retzius cells leads to memory deficits and susceptibility to epileptic seizures

Martina Riva, Stéphanie Moriceau, Annunziato Morabito, Elena Dossi, Candela Sanchez-Bellot, Andrea Navas-Olive, Francesco Dori, Fanny Ledonne, Nelson Rebola, Sabrina David, Fabrice Trovero, Magali Bartolomucci, Antoine Depaulis, Eva Coppola, Nathalie Rouach, Liset Menendez de la Prida, Franck Oury, Alessandra Pierani
ePosterNeuroscience

Absence of FKBP51 in murine microglia leads to impaired response to neuroinflammatory stimulus

Shiladitya Mitra
ePosterNeuroscience

The absence of SV2A in interneurons leads to Epilepsy

Odile Bartholome, Virginie Neirinckx, Dominique Baiwir, Gabriel Mazzucchelli, Bernard Rogister
ePosterNeuroscience

The alteration of heme metabolism affects energetic metabolism leading to neurodevelopmental defects in mice

Francesca Bertino, Tamara Monteagudo Aboy, Elisa Quarta, Dibyanti Mukherjee, Carlotta Raimondi, Tullio Genova, Chiara Riganti, Nicolas Santander, Thomas D. Arnold, Emanuela Tolosano, Deborah Chiabrando
ePosterNeuroscience

ARID1B-haploinsufficiency leads to delayed neuronal network development of iPSC-derived excitatory neurons

Ummi H. Ciptasari, Marina Hommersom, Chantal Schoenmaker, Femke Bakker, Brooke Latour, Dirk Schubert, Hans Van Bokhoven, Nael Nadif Kasri
ePosterNeuroscience

Central incretin inhibition leads to changes in brain cell energy and metabolism in a rat model of sporadic Alzheimer’s disease

Jelena Osmanovic Barilar, Ana Knezovic, Ana Babic Perhoc, Jan Homolak, Melita Salkovic-Petrisic
ePosterNeuroscience

Cerebral hypoperfusion induced by carotid stenosis leads to hypoxia in oligodendrocyte precursor cells

Narek Manukjan, Daria Majcher, Peter Leenders, Florian Caiment, Marcel Van Herwijnen, Hubert Smeets, Tim Vanmierlo, Zubair Ahmed, Daniel Fulton, Matthijs Blankesteijn, Sébastien Foulquier
ePosterNeuroscience

Claustrum lesions lead to changes in behavioural strategy during reversal learning in a spatial memory task

Vanessa Cattaud, Romain Goutagny, Jesse Jackson
ePosterNeuroscience

Channel noise leads to larger stochastic voltage fluctuations in the axon than in the soma

Mickael Zbili, Rodrigo Perin, Henry Markram, Werner Van Geit
ePosterNeuroscience

Collaboration and competition lead to long-term spatial heterosynaptic plasticity

Maximilian Eggl, Thomas Chater, Yukiko Goda, Tatjana Tchumatchenko
ePosterNeuroscience

Dynamic motor practice improves movement accuracy, force control and leads to increased corticospinal excitability compared to isometric motor practice

Malene Norup N. Stolpe, Jonas Rud Bjørndal, Patrick Wiegel, Jesper Lundbye-Jensen
ePosterNeuroscience

Early postnatal disruption of neurokinin receptor 3 function leads to irregular striatal cholinergic activity and autistic-like behaviours

Nathan Reynolds, Shaam Al Abed, Yovina Sontani, Alexandre Rcom-H'cheo-Gauthier, Beau Johnston, Nathalie Dehorter
ePosterNeuroscience

Early-life adversity induces sex-specific dysfunction of the mOFC and leads to impulsive, hyperactive, and risk-taking behaviors in juvenile male mice

Jéssica Costa, Solange Martins, Carolina Kunicki, Pedro Ferreira, Joana R. Guedes, João Peça, Ana Luísa Cardoso
ePosterNeuroscience

Failed remyelination of the non-human primate optic nerve leads to axon degeneration, retinal damages and visual dysfunction

Nadege Sarrazin, Estelle Chavret-Reculon, Corinne Bachelin, Mehdi Felfli, Rafik Arab, Sophie Gilardeau, Elena Brazhnikova, Elisabeth Dubus, Lydia Yaha-Cherif, Jean Lorenceau, Serge Picaud, Serge Rosolen, Pierre Moissonnier, Pierre Pouget, Anne Baron-Van Evercooren
ePosterNeuroscience

High Resilience of Cerebellum Across the Life-Span: Imaging Genomics Leads for identifying and validating Neuroprotective Drug Discovery

Brijesh Baghel, Anindita Bhattacharjee, Pratik Purohit, Bindu Kumari, Prasun K. Roy
ePosterNeuroscience

Increased cortical plasticity enhances one-trial memory but leads to increased interference of semantic-like memory and changes in NonREM sleep oscillations in rats

Adrian Aleman-Zapata, Irene Navarro-Lobato, Shekhar Narayanan, Milan Bogers, Kopal Agarwal, Pelin Özsezer, Anumita Samanta, Alejandra Alonso, Lisa Genzel
ePosterNeuroscience

Invisible killer: intracellular Aβ accumulation leads to endosomal/lysosomal leakage in hippocampal neurons

Yang Gao, Bengt Winblad, Sophia Schedin Weiss, Lars Tjernberg
ePosterNeuroscience

Gut microbiome depletion leads to altered neural dynamics and metabolism in the dorsal CA1 field of the hippocampus

Joshua M. Glynn, Joshua J. Strohl, Patricio T. Huerta, Joseph Carrión
ePosterNeuroscience

Microglia-specific knockdown of core clock gene Bmal1 leads to an altered behavioural phenotype and increased susceptibility to seizures in mice

Tammy Strickland, James O'Siorain, Annie Curtis, David Henshall, Cristina Reschke
ePosterNeuroscience

Phasic and tonic locus coeruleus stimulations lead to opposite valence learning via distinct adrenoceptors in the basolateral amygdala

Kyron Power, Tamunotonye Omoluabi, Tayebeh Sepahvand, Qi Yuan
ePosterNeuroscience

Photobiomodulation does not lead to visible effects on male nor female rat brain development

Alba Gutiérrez Menéndez, Marta Méndez, Jorge L. Arias
ePosterNeuroscience

Physiologically relevant light stimulation leads to local signatures of sleep pressure in the contralateral visual cortex in freely moving mice

José Prius-Mengual, Matthew Unwin, Atreyi Chakrabarty, Lukas B. Krone, Colin J. Akerman, Vladyslav V. Vyazovskiy
ePosterNeuroscience

POGZ deficiency in mice leads to ASD-like behaviors with a male-specific increase in sociability

Reut Suliman-Lavie, Sunny Yanai, Sagiv Shifman

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