The Budapest Computational Neuroscience Forum is a series of informal monthly meetings of Budapest-based computational neuroscientists and computational cognitive scientists with the aim of facilitating discussion and cooperation among researchers working in different institutes and giving an opportunity to students to present their work and get to know the comunity. Originally started in 2007, restarted in 2017 and then again in 2023 the Forum is now regularly hosted by Central European University, and followed by a social event, both open to anyone interested.
Events of the Forum are advertised on a mailing list. If you wish to be on this list or have any inquiries about the series, contact Mihály Bányai.
Upcoming meeting:
Time: May 26, Tuesday, 17:00
Location: CEU, 1051 Bp. Nádor u. 15, Room 203
Presenter: Jochen Braun, Otto-von-Guericke University Magdeburg
Title: Clickety-clack: decision-making with non-equilibrium cortical activity
Abstract: Sensory perception exhibits a puzzling intrinsic dynamic: perceived appearance changes sporadically even when the sensory scene remains fixed. The statistics of these spontaneous reversals are sufficiently consistent and informative to allow inverse modelling, which unequivocally supports discretely stochastic 'idling' at the underlying neural levels, putatively at the mesoscopic scale of cortical columns or assemblies.
What functional purpose could 'idling' cortical columns serve? When noisy sensory inputs stimulate a hierarchy of 'idling' cortical levels, the upper levels spontaneously make categorical choices. In fact, choice performance can be comparable to that of macaques (episodic choice) and to optimal Bayesian inference (continuous choice).
Non-equilibrium statistical physics explains this astonishing functionality. We show that information processing by coupled fluctuations of 'idling' cortical levels is robust and governed by a variational principle of non-equilibrium (Maximum Calibre). Discrete stochasticity ensures sensitivity and overcomes trajectory inertia. Coupling within and between cortical levels renders non-equilibrium fluctuations maximally susceptible to sensory input.
We conclude that spontaneous reversals of perception reflect a non-equilibrium neural dynamic perpetuated by intrinsic birth-death noise and destabilising interactions between cortical levels. In short, disruptive instabilities are built into the very fabric of sensory processing. This ensures active and continuous updating without new input and renders all perceptions transient and subject to revision. Perhaps endless cycles of hypotheses and validations are essential for perceptual and cognitive function.
Earlier meetings of the Forum:
April 14, 2026. Balázs Mészáros (University of Sussex): Considering Space and Time in Neural Networks
February 27, 2026. Morten L Kringelbach (University of Oxford): Whole-brain modelling. Cartography of eudaimonia and flourishing in the human brain. AND Gustavo Deco (Pompeu Fabra University): The computing brain: Explaining cognition through a realistic whole-brain anatomically constrained-reservoir model.
November 11, 2025. Zsigmond Benkő (Wigner Institute): Hidden Common Driver Reconstruction and the Anisotropic Self-Organizing Map
June 17, 2025. Keith T Murray (Wigner Institute): V1 signatures of generative computations in a discrimination task
November 5, 2024. József Konczer: Statistical Games, Playful approach to statistics. Recording here.
May 22, 2024. Nikola Milićević (Pennsylvania State University): Sensory systems and combinatorial neural codes. Recording here.
January 31, 2024. Zoltán Somogyvári (Wigner Institute): Seeing beyond the spikes: reconstructing the complete spatiotemporal membrane potential distribution from paired intra- and extracellular recordings
December 12, 2023. Máté Lengyel (Cambridge/CEU): Optimal information loading into working memory explains dynamic coding in prefrontal cortex. Recording here.
November 15, 2023. András Ecker (EPFL): Long-term plasticity induces sparse and specific synaptic changes in a biophysically detailed cortical model
October 25, 2023. Ferenc Csikor (Wigner Institute): Top-down perceptual inference shaping the activity of early visual cortex
October 4, 2023. Gábor Lengyel (University of Rochester): A General Method for Testing Bayesian Models Using Neural Data
September 1, 2023. Emmanuel Procyk (INSERM Lyon): Prefrontal neuronal dynamics, timescales, and behavioural flexibility
May 31, 2023. Atilla B. Kelemen (KOKI): Geometry of remapping in the hippocampus reflects task structure
April 26, 2023. Anna Székely (Wigner Institute): Identifying transfer learning in the reshaping of inductive biases
March 29, 2023. Merse Előd Gáspár (CEU): Discovering the internal predictive model of infants based on eye movements