Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Modelling studies on the computational function of fast temporal structurein cortical circuit activity
Autore:
Sommer, FT; Wennekers, T;
Indirizzi:
Univ Ulm, Dept Neural Informat Proc, D-89069 Ulm, Germany Univ Ulm Ulm Germany D-89069 Neural Informat Proc, D-89069 Ulm, Germany Max Planck Inst Math Sci, D-04103 Leipzig, Germany Max Planck Inst Math Sci Leipzig Germany D-04103 -04103 Leipzig, Germany
Titolo Testata:
JOURNAL OF PHYSIOLOGY-PARIS
fascicolo: 5-6, volume: 94, anno: 2000,
pagine: 473 - 488
SICI:
0928-4257(200009/12)94:5-6<473:MSOTCF>2.0.ZU;2-G
Fonte:
ISI
Lingua:
ENG
Soggetto:
ASSOCIATIVE MEMORY; NEURAL NETWORKS; STORAGE CAPACITY; VISUAL-CORTEX; SPIKING NEURONS; NMDA CHANNELS; SYNCHRONIZATION; OSCILLATIONS; RETRIEVAL; PATTERNS;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
90
Recensione:
Indirizzi per estratti:
Indirizzo: Sommer, FT Univ Ulm, Dept Neural Informat Proc, D-89069 Ulm, Germany Univ Ulm Ulm Germany D-89069 ormat Proc, D-89069 Ulm, Germany
Citazione:
F.T. Sommer e T. Wennekers, "Modelling studies on the computational function of fast temporal structurein cortical circuit activity", J PHYSL-PAR, 94(5-6), 2000, pp. 473-488

Abstract

The interplay between modelling and experimental studies can support the exploration of the function of neuronal circuits in the cortex. We exemplifysuch an approach with a study on the role of spike timing and gamma-oscillations in associative memory in strongly connected circuits of cortical neurones. It is demonstrated how associative memory studies on different levels of abstraction can specify the functionality to be expected in real cortical neuronal circuits. In our model overlapping random configurations of sparse cell populations correspond to memory items that are stored by simple Hebbian coincidence learning. This associative memory task will be implemented with biophysically well tested compartmental neurones developed by Pinsky and Rinzel [58]. We ran simulation experiments to study memory recall intwo network architectures: one interconnected pool of cells, and two reciprocally connected pools. When recalling a memory by stimulating a spatiallyoverlapping set of cells, the completed pattern is coded by an event of synchronized single spikes occurring after 25-60 ms. These fast associations are performed even at a memory load corresponding to the memory capacity ofoptimally tuned formal associative networks (> 0.1 bit/synapse). With tonic stimulation or feedback loops in the network the neurones fire periodically in the gamma-frequency range (20-80 Hz). With fast changing inputs memory recall can be switched between items within a single gamma cycle. Thus, oscillation is nor a primary coding feature necessary for associative memory. However, it accompanies reverberatory feedback providing an improved iterative memory recall completed after a few gamma cycles (60-260 ms). In the bidirectional architecture reverberations do not express in a rigid phase locking between the pools. For small stimulation sets bursting occurred in these cells acting as a supportive mechanism for associative memory. (C) 2000 Elsevier Science Ltd. Published by Editions scientifiques et medicales Elsevier SAS.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 09/07/20 alle ore 17:14:28