Assemblies, synapse clustering and network topology interact with plasticity to explain structure-function relationships of the cortical connectome

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Aug. 7, 2023

Synaptic plasticity underlies the brain's ability to learn and adapt. While experiments in brain slices have revealed mechanisms protocols for induction of between pairs neurons, how these synaptic changes are coordinated biological neuronal networks ensure emergence learning remains poorly understood. Simulation modeling emerged as important tools study plastic networks, but yet achieve a scale that incorporates realistic network structure, active dendrites, multi-synapse interactions, key determinants plasticity. To rise this challenge, we endowed an existing large-scale cortical model, incorporating data-constrained dendritic processing multi-synaptic connections, with calcium-based model functional captures diversity excitatory connections extrapolated vivo-like conditions. This allowed us dendrites structure interact shape stimulus representations at microcircuit level. In our exploratory simulations, acted sparsely specifically, firing rates weight distributions remained stable without additional homeostatic mechanisms. At circuit level, found was driven by co-firing stimulus-evoked assemblies, spatial clustering synapses on topology connectivity. As result changes, became more reliable stimulus-specific responses. We confirmed testable predictions MICrONS datasets, openly available electron microscopic reconstruction large volume tissue. Our results quantify architecture higher-order microcircuits play central role provide foundation elucidating their learning.

Language: Английский

Context-Aware Compliance-based Access Control (CACBAC)

SSRN Electronic Journal, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

Language: Английский

Cortical cell assemblies and their underlying connectivity: anin silicostudy

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Feb. 24, 2023

Abstract Recent developments in experimental techniques have enabled simultaneous recordings from thousands of neurons, enabling the study functional cell assemblies. However, determining patterns synaptic connectivity giving rise to these assemblies remains challenging. To address this, we developed a complementary, simulation-based approach, using detailed, large-scale cortical network model. Using combination established methods detected stimulus-evoked spiking activity 186,665 neurons. We studied how structure underlies assembly composition, quantifying effects thalamic innervation, recurrent connectivity, and spatial arrangement synapses on den-drites. determined that features reduce up 30%, 22%, 10% uncertainty neuron belonging an assembly. The were activated stimulus-specific sequence grouped based their position sequence. found different groups affected degrees by structural considered. Additionally, was more predictive membership if its direction aligned with temporal order activation, it originated strongly interconnected populations, clustered dendritic branches. In summary, reversing Hebb’s postulate, showed cells are wired together, fire interact shape emergence This includes qualitative aspect connectivity: not just amount, but also local matters; subcellular level form clustering presence specific motifs. connectivity-based characterization creates opportunity plasticity at level, beyond strictly pairwise interactions.

Language: Английский