Event Abstract Back to Event On the origin of low frequency fluctuations in the brain resting state Brain imaging studies (fMRI, MEG and EEG) have shown that the brain exhibits large scale very slow fluctuations (<0.1 Hz). These fluctuations even appear when the subject is not engaged in a particular task, in the so-called “resting state”. In certain cases, these fluctuations have been shown to correlate with behavioral performance. Spatially, the brain exhibits large-scale coactivated networks which are believed to support a fundamental functional organization of the brain. As the brain constantly receives external inputs, this spatiotemporal pattern of activity in the resting state is a priori surprising. What is the origin of these fluctuations? Are they induced by the brain alone? If yes, do they result from the interaction between brain areas or are they locally created in the neural tissue? In this study, we consider a single local neural network and investigate the possibility of the emergence of spontaneous fluctuations, even when the network receives no external fluctuations. The network is composed of excitatory and inhibitory integrate-and-fire type of neurons, sparsely connected as in the cortex, and with instantaneous synapses. Each neuron receives external spike train inputs. We formulate the mean-field description of this model and write the corresponding Fokker-Planck equation (FPE) which describes the evolution of the neuronal membrane potential probability distribution. We investigate analytically the stability of the stationary solution of the FPE for constant input. For low inputs and a class of neuron models, we show that this solution becomes unstable in the presence of synaptic delays and in the inhibition dominated regime. Numerical simulations confirm that the neuronal firing rate oscillates in the predicted parameter region, at a frequency which decreases with the input. Our results suggest that the low frequency fluctuations could be intrinsic and originate locally. The next step is to explore the type of dynamics generated when, as in he brain, such local networks are the nodes of a larger scale network, and to see if the observed spatiotemporal patterns of activity can emerge when a realistic interareal connectivity and delay structure is taken into account. Conference: Computational and systems neuroscience 2009, Salt Lake City, UT, United States, 26 Feb - 3 Mar, 2009. Presentation Type: Poster Presentation Topic: Poster Presentations Citation: (2009). On the origin of low frequency fluctuations in the brain resting state. Front. Syst. Neurosci. Conference Abstract: Computational and systems neuroscience 2009. doi: 10.3389/conf.neuro.06.2009.03.198 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 03 Feb 2009; Published Online: 03 Feb 2009. Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Google Google Scholar PubMed Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.