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Jan Fousek

Publications and source records attributed to Jan Fousek.

4 recordsLinked to original sources

Functional Whole-Brain Models: A New Framework for Unifying Brain Structure and Cognitive Function

Contemporary computational neuroscience features two prominent modeling traditions. Bottom-up whole-brain modeling (WBM) builds biophysically detailed simulations of brain structure and dynamics, whereas top-down neuroconnectionism optimizes deep neural networks for functional performance. Each has achieved remarkable success yet remains incomplete with WBMs lacking functional competence and neuroconnectionist models showing limited biological grounding. Here we propose functional whole-brain models (fWBMs) as a unified modeling paradigm that integrates structural and dynamical realism with task-performing capacity. fWBMs are defined by four minimal criteria: structural grounding in empirical connectomes and regional biology, continuous-time dynamical realism, functional competence across cognitive domains, and mappable observables to neuroimaging, electrophysiologcal and behavioral data. To formalize this integration, we establish a three-pillar roadmap across short-, mid-, and long-term horizons, and outline the scientific and clinical opportunities this paradigm enables. We argue that the disciplined pursuit of this integrative vision will generate the tools, common language, and cross-scale hypotheses needed to advance our understanding of the brain.

q-bio.NC

TVB C++: A Fast and Flexible Back-End for The Virtual Brain

This paper introduces TVB C++, a streamlined and fast C++ Back-End for The Virtual Brain (TVB), a renowned platform and a benchmark tool for full-brain simulation. TVB C++ is engineered with speed as a primary focus while retaining the flexibility and ease of use characteristic of the original TVB platform. Positioned as a complementary tool, TVB serves as a prototyping platform, whereas TVB C++ becomes indispensable when performance is paramount, particularly for large-scale simulations and leveraging advanced computation facilities like supercomputers. Developed as a TVB-compatible Back-End, TVB C++ seamlessly integrates with the original TVB implementation, facilitating effortless usage. Users can easily configure TVB C++ to execute the same code as in TVB but with enhanced performance and parallelism capabilities.

q-bio.NC

Brain Modelling as a Service: The Virtual Brain on EBRAINS

The Virtual Brain (TVB) is now available as open-source cloud ecosystem on EBRAINS, a shared digital research platform for brain science. It offers services for constructing, simulating and analysing brain network models (BNMs) including the TVB network simulator; magnetic resonance imaging (MRI) processing pipelines to extract structural and functional connectomes; multiscale co-simulation of spiking and large-scale networks; a domain specific language for automatic high-performance code generation from user-specified models; simulation-ready BNMs of patients and healthy volunteers; Bayesian inference of epilepsy spread; data and code for mouse brain simulation; and extensive educational material. TVB cloud services facilitate reproducible online collaboration and discovery of data assets, models, and software embedded in scalable and secure workflows, a precondition for research on large cohort data sets, better generalizability and clinical translation.

cs.CE

Patterning of dielectric nanoparticles using dielectrophoretic forces generated by ferroelectric polydomain films

A theoretical study of a dielectrophoretic force, i.e. the force acting on an electrically neutral particle in the inhomogeneous electric field, which is produced by a ferroelectric domain pattern, is presented. It has been shown by several researchers that artificially prepared domain patterns with given geometry in ferroelectric single crystals represent an easy and flexible method for patterning dielectric nanoobjects using dielectrophoretic forces. The source of the dielectrophoretic force is a strong and highly inhomogeneous (stray) electric field, which exists in the vicinity of the ferroelectric domain walls at the surface of the ferroelectric film. We analyzed dielectrophoretic forces in the model of a ferroelectric film of a given thickness with a lamellar 180${}^\circ$ domain pattern. The analytical formula for the spatial distribution of the stray field in the ionic liquid above the top surface of the film is calculated including the effect of free charge screening. The spatial distribution of the dielectrophoretic force produced by the domain pattern is presented. The numerical simulations indicate that the intersection of the ferroelectric domain wall and the surface of the ferroelectric film represents a trap for dielectric nanoparticles in the case of so called positive dielectrophoresis. The effects of electrical neutrality of dielectric nanoparticles, free charge screening due to the ionic nature of the liquid, domain pattern geometry, and the Brownian motion on the mechanism of nanoparticle deposition and the stability of the deposited pattern are discussed.

cond-mat.mes-hall