Build and evaluate deep-learning models for biological prediction using Python and Jupyter notebooks. Lectures and collaborative exercises develop convolutional networks for classification, regression and image segmentation, with attention to preprocessing, augmentation, class imbalance, cross-validation and overfitting. Later sessions explore learning-rate and training-duration choices, recurrent networks and applications to omics data. Participants interpret model performance and discuss their own research problems. 2026-11-23–2026-11-27, 14:00–20:00 daily, Europe/Berlin (CET, UTC+01:00). O
Flexible analog computation in low-rank balanced spiking networks
Alfonso Renart · Champalimaud Centre for the Unknown, Lisbon
Wed, Nov 26, 2025 · 16:00 UTC
Recurrent networks with balanced excitation-inhibition explain a wide range of neurophysiological observations, but can only implement a limited set of transformations on their input. On the other hand networks of firing-rate units with low-rank connectivity have universal computational capabilities, but do not work with spikes or generate noise self-consistently. Although empirical approaches to merge these two computational frameworks have been constructed, there is no established theory describing their unification. Here we develop such a theory. We study analytically and numerically networ
On topological data analysis and Hopfield-like network models - with Carina Curto - #7
Theoretical Neuroscience Podcast
Feb 3, 2024
Carina Curto explains applications of topology to neural recordings and discusses mathematical models of recurrent networks.
The role of sub-population structure in computations through neural dynamics
Srdjan Ostojic · École normale supérieure
Fri, May 19, 2023 · 06:30 UTC
Neural computations are currently conceptualised using two separate approaches: sorting neurons into functional sub-populations or examining distributed collective dynamics. Whether and how these two aspects interact to shape computations is currently unclear. Using a novel approach to extract computational mechanisms from recurrent networks trained on neuroscience tasks, we show that the collective dynamics and sub-population structure play fundamentally complementary roles. Although various tasks can be implemented in networks with fully random population structure, we found that flexible i
Convex neural codes in recurrent networks and sensory systems
Vladimir Itskov · The Pennsylvania State University
Wed, Dec 14, 2022 · 05:00 UTC
Neural activity in many sensory systems is organized on low-dimensional manifolds by means of convex receptive fields. Neural codes in these areas are constrained by this organization, as not every neural code is compatible with convex receptive fields. The same codes are also constrained by the structure of the underlying neural network. In my talk I will attempt to provide answers to the following natural questions: (i) How do recurrent circuits generate codes that are compatible with the convexity of receptive fields? (ii) How can we utilize the constraints imposed by the convex receptive
Computation in the neuronal systems close to the critical point
Anna Levina · Universität Tübingen
Sat, Apr 30, 2022 · 00:00 UTC
It was long hypothesized that natural systems might take advantage of the extended temporal and spatial correlations close to the critical point to improve their computational capabilities. However, on the other side, different distances to criticality were inferred from the recordings of nervous systems. In my talk, I discuss how including additional constraints on the processing time can shift the optimal operating point of the recurrent networks. Moreover, the data from the visual cortex of the monkeys during the attentional task indicate that they flexibly change the closeness to the criti
Selective signal processing by spontaneous synchronization
Maik Schünemann,Udo Ernst · COSYNE 2022
Sat, Mar 19, 2022
Neural information processing in dynamic, natural environments requires the brain to flexibly allocate limited computational resources to varying task demands. One example is selective attention in the visual system, which allows to preferentially route signals from behaviourally relevant stimuli to downstream visual areas, while suppressing irrelevant visual information. It is an open question which neural mechanisms realize selective routing, and how this process is controlled. Here we propose that spontaneous synchronization in recurrent networks is the key mechanism for selective processin
Norse: A library for gradient-based learning in Spiking Neural Networks
Jens Egholm Pedersen · KTH Royal Institute of Technology
Wed, Nov 3, 2021 · 17:35 UTC
We introduce Norse: An open-source library for gradient-based training of spiking neural networks. In contrast to neuron simulators which mainly target computational neuroscientists, our library seamlessly integrates with the existing PyTorch ecosystem using abstractions familiar to the machine learning community. This has immediate benefits in that it provides a familiar interface, hardware accelerator support and, most importantly, the ability to use gradient-based optimization. While many parallel efforts in this direction exist, Norse emphasizes flexibility and usability in three ways. Use
A theory for Hebbian learning in recurrent E-I networks
Samuel Eckmann · Gjorgjieva lab, Max Planck Institute for Brain Research, Frankfurt, Germany
Thu, May 20, 2021 · 16:30 UTC
The Stabilized Supralinear Network is a model of recurrently connected excitatory (E) and inhibitory (I) neurons with a supralinear input-output relation. It can explain cortical computations such as response normalization and inhibitory stabilization. However, the network's connectivity is designed by hand, based on experimental measurements. How the recurrent synaptic weights can be learned from the sensory input statistics in a biologically plausible way is unknown. Earlier theoretical work on plasticity focused on single neurons and the balance of excitation and inhibition but did not cons
A geometric framework to predict structure from function in neural networks
James Fitzgerald · Janelia Research Campus
Wed, Feb 3, 2021 · 05:00 UTC
The structural connectivity matrix of synaptic weights between neurons is a critical determinant of overall network function. However, quantitative links between neural network structure and function are complex and subtle. For example, many networks can give rise to similar functional responses, and the same network can function differently depending on context. Whether certain patterns of synaptic connectivity are required to generate specific network-level computations is largely unknown. Here we introduce a geometric framework for identifying synaptic connections required by steady-state r
The emergence and modulation of time in neural circuits and behavior
Luca Mazzucato · University of Oregon
Wed, Nov 25, 2020 · 05:00 UTC
Spontaneous behavior in animals and humans shows a striking amount of variability both in the spatial domain (which actions to choose) and temporal domain (when to act). Concatenating actions into sequences and behavioral plans reveals the existence of a hierarchy of timescales ranging from hundreds of milliseconds to minutes. How do multiple timescales emerge from neural circuit dynamics? How do circuits modulate temporal responses to flexibly adapt to changing demands? In this talk, we will present recent results from experiments and theory suggesting a new computational mechanism generating
Cross-correlation--response relation for spike-driven neurons
Jakob Stubenrauch, Benjamin Lindner · Bernstein Conference 2024
We consider two spiking neurons, with one neuron driving the other. From a statistical point of view, the relationship between the two neurons can be quantified by (i) the cross-correlation $C(t,t^{\prime})$ of the two spike trains, a measure of similarity of spontaneous fluctuations, and (ii) the linear response $K(t,t^{\prime})$ of the driven neuron's rate to a rate perturbation of the driving neuron. Connecting the two statistics, we analytically derive a simple cross-correlation–response relation (CRR), $C(t,t^{\prime})=K(t,t^{\prime})\lambda(t^{\prime})$, for an arbitrary model of the dr
Synaptic Upscaling Amplifies Chaotic Dynamics in Recurrent Networks of Rate Neurons
Farhad Razi, Fleur Zeldenrust · Bernstein Conference 2024
Increasing the strength of synaptic connections (synaptic upscaling) within networks of randomly connected neurons transitions the internal dynamics from stationary to a chaotic regime [1, 2]. Synaptic upscaling in neural networks improves learning speed, accuracy, and robustness [3] and enhances the dimensionality of internal dynamics in response to external stimuli [2], by boosting chaotic activity. Nonetheless, the direct link between synaptic upscaling, the dimensionality of the network activity, and and enhanced computational capacity of neural networks for learning tasks remains unclear.
Continuous quasi-attractors thrive on irregularity, up to a limit
Alessandro Treves, Francesca Schönsberg, Remi Monasson · FENS Forum 2024
Recent research involving bats navigating lengthy tunnels has confirmed that hippocampal place cells can be active at multiple locations, with considerable variability in place field size and peak rate. In a recurrent networks, such variability implies quenched disorder in the synaptic weights, impeding the establishment of a continuous manifold of fixed points. If most positions in space are not any longer fixed points, is the popular notion of continuous attractors still relevant? What would be the neural dynamics underlying retrieval of spatial representations?We study the dynamics of recur