Seminars
September 2021
An Ideal Cortical Map: Towards a multi-dimensional account of cortical organisation
Casey Paquola· Forschungszentrum Jülich
Sat, Sep 4 · 00:00 UTC
Von Economo stated that an "Ideal Cortical Map" would look very different to a parcellation. He suggested that an Ideal Cortical Map would involve the superimposition of many different cortical maps, with changes in each map shown at every single point. In line with this idea, I will discuss our recent research on identifying principal dimensions of cortical differentiation. In particular, I will highlight large-scale patterns of cytoarchitectural differentiation that can be observed using post mortem histology or in vivo microstructure-sensitive MRI. I aim to show how this approach provides a cohesive framework to understand cortical organisation across multiple biological scales. This allows us to formulate new ideas on the organisation and function of the brain regions (eg: mesiotemporal lobe), networks (eg: DMN) and the whole cortex.
Metacognition for past and future decision making in primates
Kentaro Miyamoto· RIKEN CBS
Fri, Sep 3 · 23:00 UTC
As Socrates said that "I know that I know nothing," our mind's function to be aware of our ignorance is essential for abstract and conceptual reasoning. However, the biological mechanism to enable such a hierarchical thought, or meta-cognition, remained unknown. In the first part of the talk, I will demonstrate our studies on the neural mechanism for metacognition on memory in macaque monkeys. In reality, awareness of ignorance is essential not only for the retrospection of the past but also for the exploration of novel unfamiliar environments for the future. However, this proactive feature of metacognition has been understated in neuroscience. In the second part of the talk, I will demonstrate our studies on the neural mechanism for prospective metacognitive matching among uncertain options prior to perceptual decision making in humans and monkeys. These studies converge to suggest that higher-order processes to self-evaluate mental state either retrospectively or prospectively are implemented in the primate neural networks.
Cluster Headache: Improving Therapy for the Worst Pain Experienced by Humans
Peter Goadsby· King's College London, UK & UCLA, USA
Fri, Sep 3 · 16:00 UTC
Cluster headache is a brain disorder dominated clinically by dreadful episodes of excruciating pain with a circadian pattern and most often focused in bouts with circannual periodicity. As we have understood its neurobiology new therapies, including those directed at calcitonin gene-related peptide, are helpful improve the lives of sufferers.
How to turn a Machine Learning Use Case into a Successful Startup
CapeAI
Fri, Sep 3 · 14:00 UTC · Online
Have a great idea involving AI? Want to launch your own business? It takes many iterations before an idea becomes a startup. Lots of coffee, heartache, and git reverts fuel these iterations. We have learned a lot from Cape AI's own incubated startup, Moonshop, Africa's first autonomous microstore. Watch the demo here: https://www.youtube.com/watch?v=odX6kxhLFC4 Attend our virtual roadshow event to hear lightning talks on creating proofs of concept, failing fast, funding models, selecting and growing a team, finding customers/clients, and building your brand. Afterwards, there will be a short break, then a panel discussion where members of the Cape AI team will answer questions from the audience.
PiVR: An affordable and versatile closed-loop platform to study unrestrained sensorimotor behavior
David Tadres and Matthieu Louis· University of California, Santa Barbara
Fri, Sep 3 · 07:00 UTC
PiVR is a system that allows experimenters to immerse small animals into virtual realities. The system tracks the position of the animal and presents light stimulation according to predefined rules, thus creating a virtual landscape in which the animal can behave. By using optogenetics, we have used PiVR to present fruit fly larvae with virtual olfactory realities, adult fruit flies with a virtual gustatory reality and zebrafish larvae with a virtual light gradient. PiVR operates at high temporal resolution (70Hz) with low latencies (<30 milliseconds) while being affordable (<US$500) and easy to build (<6 hours). Through extensive documentation (www.PiVR.org), this tool was designed to be accessible to a wide public, from high school students to professional researchers studying systems neuroscience in academia.
Research seminar: How actin pulls the nucleus through constrictions
Fri, Sep 3 · 05:30 UTC
Tutorial: Cell mimics to study active movements and deformations by actin assembly
Fri, Sep 3 · 05:00 UTC
Multisensory self in spatial navigation
Olaf Blanke· Swiss Federal Institute of Technology (EPFL)
Thu, Sep 2 · 16:00 UTC
Storythinking: Why Your Brain is Creative in Ways that Computer AI Can't Ever Be
Angus Fletcher· Ohio State
Wed, Sep 1 · 17:30 UTC
Computer AI thinks differently from us, which is why it's such a useful tool. Thanks to the ingenuity of human programmers, AI's different method of thinking has made humans redundant at certain human tasks, such as chess. Yet there are mechanical limits to how far AI can replicate the products of human thinking. In this talk, we'll trace one such limit by exploring how AI and humans create differently. Humans create by reverse-engineering tools or behaviors to accomplish new actions. AI creates by mix-and-matching pieces of preexisting structures and labeling which combos are associated with positive and negative results. This different procedure is why AI cannot (and will never) learn to innovate technology or tactics and why it also cannot (and will never) learn to generate narratives (including novels, business plans, and scientific hypotheses). It also serves as a case study in why there's no reason to believe in "general intelligence" and why computer AI would have to partner with other mechanical forms of AI (run on non-computer hardware that, as of yet, does not exist, and would require humans to invent) for AI to take over the globe.
In search of me: a theoretical approach to identify the neural substrate of consciousness
Shuntaro Sasai· Araya Inc.
Wed, Sep 1 · 00:00 UTC
A major neuroscientific challenge is to identify the neural mechanisms that support consciousness. Though experimental studies have accumulated evidence about the location of the neural substrate of consciousness, we still lack a full understanding of why certain brain areas, but not others, can support consciousness. In this talk, I will give an overview of our approach, taking advantage of the theoretical framework provided by Integrated Information Theory (IIT). First, I will introduce results showing that a maximum of integrated information within the human brain matches our best evidence concerning the location of the NSC, supporting the IIT’s prediction. Furthermore, I will discuss the possibility that the NSC can change its location and even split into two depending on the task demand. Finally, based on some graph-theoretical analyses, I will argue that the ability of different brain regions to contribute or not to consciousness depends on specific properties of their anatomical connectivity, which determines their ability to support high integrated information.
August 2021
LONG-ACTING ANTIPSYCHOTICS: OPTION DOWN THE ROCKY ROAD, NICE TO HAVE OR ESSENTIAL CHOICE?
Christoph U. Correll· The Donald and Barbara Zucker School of Medicine at Hofstra/Northwell New York, USA & Charité – Universitätsmedizin Berlin, Berlin, Germany
Tue, Aug 31 · 18:30 UTC
Time and again we are faced with the question at what point in the treatment of schizophrenia a depot formulation should be used. The data on the so-called LAIs (Long-Acting Injectables) has steadily increased in recent years. Today, we have very good evidence for the early use of depot therapies. However, the willingness and consent of the patient for this form of pharmacotherapy remains central to the successful use of LAIs. In his lecture, Prof. Correll will talk about the current evidence for the use of LAIs summarizing the latest studies.
Theory of activity-powered interface
Zhihong You· University of California, Santa Barbara
Mon, Aug 30 · 00:00 UTC
Interfaces and membranes are ubiquitous in cellular systems across various scales. From lipid membranes to the interfaces of biomolecular condensates inside the cell, these borders not only protect and segregate the inner components from the outside world, but also are actively participating in mechanical regulation and biochemical reaction of the cell. Being part of a living system, these interfaces (membranes) are usually active and away from equilibrium. Yet, it's still not clear how activity can tweak their equilibrium dynamics. Here, I will introduce a model system to tackle this problem. We put together a passive fluid and an active nematics, and study the behavior of this liquid-liquid interface. Whereas thermal fluctuation of such an interface is too weak to be observed, active stress can easily force the interface to fluctuate, overhang, and even break up. In the presence of a wall, the active phase exhibits superfluid-like behavior: it can climb up walls -- a phenomenon we call activity-induced wetting. I will show how to formulate theories to capture these phenomena, highlighting the nontrivial effects of active stress. Our work not only demonstrates that activity can introduce interesting features to an interface, but also sheds light on controlling interfacial properties using activity.
Introducing YAPiC: An Open Source tool for biologists to perform complex image segmentation with deep learning
Christoph Möhl· Core Research Facilities, German Center of Neurodegenerative Diseases (DZNE) Bonn.
Fri, Aug 27 · 07:00 UTC
Robust detection of biological structures such as neuronal dendrites in brightfield micrographs, tumor tissue in histological slides, or pathological brain regions in MRI scans is a fundamental task in bio-image analysis. Detection of those structures requests complex decision making which is often impossible with current image analysis software, and therefore typically executed by humans in a tedious and time-consuming manual procedure. Supervised pixel classification based on Deep Convolutional Neural Networks (DNNs) is currently emerging as the most promising technique to solve such complex region detection tasks. Here, a self-learning artificial neural network is trained with a small set of manually annotated images to eventually identify the trained structures from large image data sets in a fully automated way. While supervised pixel classification based on faster machine learning algorithms like Random Forests are nowadays part of the standard toolbox of bio-image analysts (e.g. Ilastik), the currently emerging tools based on deep learning are still rarely used. There is also not much experience in the community how much training data has to be collected, to obtain a reasonable prediction result with deep learning based approaches. Our software YAPiC (Yet Another Pixel Classifier) provides an easy-to-use Python- and command line interface and is purely designed for intuitive pixel classification of multidimensional images with DNNs. With the aim to integrate well in the current open source ecosystem, YAPiC utilizes the Ilastik user interface in combination with a high performance GPU server for model training and prediction. Numerous research groups at our institute have already successfully applied YAPiC for a variety of tasks. From our experience, a surprisingly low amount of sparse label data is needed to train a sufficiently working classifier for typical bioimaging applications. Not least because of this, YAPiC has become the "standard weapon” for our core facility to detect objects in hard-to-segement images. We would like to present some use cases like cell classification in high content screening, tissue detection in histological slides, quantification of neural outgrowth in phase contrast time series, or actin filament detection in transmission electron microscopy.
The ALBA Network is organizing a webinar on LGBTQIA+ inclusion and visibility. This special event will feature a panel of established scientists in brain research who identify as LGBTQIA+. Speaker will discuss their goals, challenges and successes while navigating academia as part of the LGBTQIA+ community. Registration is free but mandatory.
Statistical Summary Representations in Identity Learning: Exemplar-Independent Incidental Recognition
Yaren Koca· University of Regina
Thu, Aug 26 · 16:00 UTC
The literature suggests that ensemble coding, the ability to represent the gist of sets, may be an underlying mechanism for becoming familiar with newly encountered faces. This phenomenon was investigated by introducing a new training paradigm that involves incidental learning of target identities interspersed among distractors. The effectiveness of this training paradigm was explored in Study 1, which revealed that unfamiliar observers who learned the faces incidentally performed just as well as the observers who were instructed to learn the faces, and the intervening distractors did not disrupt familiarization. Using the same training paradigm, ensemble coding was investigated as an underlying mechanism for face familiarization in Study 2 by measuring familiarity with the targets at different time points using average images created either by seen or unseen encounters of the target. The results revealed that observers whose familiarity was tested using seen averages outperformed the observers who were tested using unseen averages, however, this discrepancy diminished over time. In other words, successful recognition of the target faces became less reliant on the previously encountered exemplars over time, suggesting an exemplar-independent representation that is likely achieved through ensemble coding. Taken together, the results from the current experiment provide direct evidence for ensemble coding as a viable underlying mechanism for face familiarization, that faces that are interspersed among distractors can be learned incidentally.
Deciphering the pathogenesis of migraine with human models
Messoud Ashina· University of Copenhagen, Denmark
Wed, Aug 25 · 16:00 UTC
Integration of „environmental“ information in the neuronal epigenome
Geraldine Zimmer-Bensch· Functional Epigenetics in the Animal Model, Institute of Biology II, RWTH Aachen, Aachen, Germany
Wed, Aug 25 · 16:00 UTC
The inhibitory actions of the heterogeneous collection of GABAergic interneurons tremendously influence cortical information processing, which is reflected by diseases like autism, epilepsy and schizophrenia that involve defects in cortical inhibition. Apart from the regulation of physiological processes like synaptic transmission, proper interneuron function also relies on their correct development. Hence, decrypting regulatory networks that direct proper cortical interneuron development as well as adult functionality is of great interest, as this helps to identify critical events implicated in the etiology of the aforementioned diseases. Thereby, extrinsic factors modulate these processes and act on cell- and stage-specific transcriptional programs. Herein, epigenetic mechanisms of gene regulation, like DNA methylation executed by DNA methyltransferases (DNMTs), histone modifications and non-coding RNAs, call increasing attention in integrating “environmental information” in our genome and sculpting physiological processes in the brain relevant for human mental health. Several studies associate altered expression levels and function of the DNA methyltransferase 1 (DNMT1) in subsets of embryonic and adult cortical interneurons in patients diagnosed with schizophrenia. Although accumulating evidence supports the relevance of epigenetic signatures for instructing cell type-specific development, only very little is known about their functional implications in discrete developmental processes and in subtype-specific maturation of cortical interneurons. Similarly, little is known about the role of DNMT1 in regulating adult interneurons functionality. This talk will provide an overview about newly identified and roles DNMT1 has in orchestrating cortical interneuron development and adult function. Further, this talk will report about the implications of lncRNAs in mediating site-specific DNA methylation in response to discrete external stimuli.
Why do we need a formal ontology of cognition, and what should it look like?
Russ Poldrack· Stanford University
Fri, Aug 20 · 17:00 UTC
In my talk I will discuss the concept of a cognitive ontology, which defines the parts of the mind that psychologists and neuroscientsts aim to study. I will discuss the way in which ontologies have traditionally been defined, and then discuss ways in which ontology might be reconsidered in the context of computational approaches to cognition.
Physics of flow sensing by cancer cells
Andrew Mugler· University of Pittsburg
Fri, Aug 20 · 05:30 UTC
Bacteria, soil, carbon, and biosurfactants:From climate related themes to bacterial spreading in unsaturated porous media
Howard Stone· Princeton
Fri, Aug 20 · 05:00 UTC