Network mechanisms underlying the role of oscillations in cognitive tasks
Schmidt, Helmut (Centre de Recerca Matemàtica)
Avitabile, Daniele (Inria Sophia Antipolis Méditerranée Research Centre)
Montbrió, Ernest (Universitat Pompeu Fabra. Centre de Cognició i Cervell)
Roxin, Alex (Universitat Autònoma de Barcelona. Departament de Matemàtiques)

Data:	2018
Resum:	Oscillatory activity robustly correlates with task demands during many cognitive tasks. However, not only are the network mechanisms underlying the generation of these rhythms poorly understood, but it is also still unknown to what extent they may play a functional role, as opposed to being a mere epiphenomenon. Here we study the mechanisms underlying the influence of oscillatory drive on network dynamics related to cognitive processing in simple working memory (WM), and memory recall tasks. Specifically, we investigate how the frequency of oscillatory input interacts with the intrinsic dynamics in networks of recurrently coupled spiking neurons to cause changes of state: the neuronal correlates of the corresponding cognitive process. We find that slow oscillations, in the delta and theta band, are effective in activating network states associated with memory recall. On the other hand, faster oscillations, in the beta range, can serve to clear memory states by resonantly driving transient bouts of spike synchrony which destabilize the activity. We leverage a recently derived set of exact mean-field equations for networks of quadratic integrate-and-fire neurons to systematically study the bifurcation structure in the periodically forced spiking network. Interestingly, we find that the oscillatory signals which are most effective in allowing flexible switching between network states are not smooth, pure sinusoids, but rather burst-like, with a sharp onset. We show that such periodic bursts themselves readily arise spontaneously in networks of excitatory and inhibitory neurons, and that the burst frequency can be tuned via changes in tonic drive. Finally, we show that oscillations in the gamma range can actually stabilize WM states which otherwise would not persist. Oscillations are ubiquitous in the brain and often correlate with distinct cognitive tasks. Nonetheless their role in shaping network dynamics, and hence in driving behavior during such tasks is poorly understood. Here we provide a comprehensive study of the effect of periodic drive on neuronal networks exhibiting multistability, which has been invoked as a possible circuit mechanism underlying the storage of memory states. We find that oscillatory drive in low frequency bands leads to robust switching between stored patterns in a Hopfield-like model, while oscillations in the beta band suppress sustained activity altogether. Furthermore, inputs in the gamma band can lead to the creation of working-memory states, which otherwise do not exist in the absence of oscillatory drive.
Ajuts:	Ministerio de Economía y Competitividad MDM-2014-0445 Ministerio de Economía y Competitividad MTM2015-71509-C2-1-R European Commission 642563 Ministerio de Economía y Competitividad PSI2016-75688-P Ministerio de Economía y Competitividad PCIN-2015-127 Ministerio de Economía y Competitividad BFU2012-33413
Drets:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Llengua:	Anglès
Document:	Article ; recerca ; Versió publicada
Publicat a:	PLoS computational biology, Vol. 14, Issue 9 (September 2018) , art. e1006430, ISSN 1553-7358

DOI: 10.1371/journal.pcbi.1006430
PMID: 30188889

24 p, 7.9 MB

El registre apareix a les col·leccions:
Articles > Articles de recerca
Articles > Articles publicats