Title
Dynamics of self-sustained asynchronous-irregular activity in random networks of spiking neurons with strong synapses.
Abstract
Random networks of integrate-and-fire neurons with strong current-based synapse scan, unlike previously believed, assume stable states of sustained asynchronous and irregular firing, even without external random background or pacemaker neurons. We analyze the mechanisms underlying the emergence, lifetime and irregularity of such self-sustained activity states. We first demonstrate how the competition between the mean and the variance of the synaptic input leads to a non-monotonic firing-rate transfer in the network. Thus, by increasing the synaptic coupling strength, the system can become bistable: In addition to the quiescent state, a second stable fixed-point at moderate firing rates can emerge by a saddle-node bifurcation. Inherently generated fluctuations of the population firing rate around this non-trivial fixed-point can trigger transitions into the quiescent state. Hence, the trade-off between the magnitude of the population-rate fluctuations and the size of the basin of attraction of the non-trivial rate fixed-point determines the onset and the lifetime of self-sustained activity states. During self-sustained activity, individual neuronal activity is more overhighly irregular, switching between long periods of low firing rate to short burst like states. We show that this is an effect of the strong synaptic weights and the finite time constant of synaptic and neuronal integration, and can actually serve to stabilize the self-sustained state.
Year
DOI
Venue
2014
10.3389/fncom.2014.00136
FRONTIERS IN COMPUTATIONAL NEUROSCIENCE
Keywords
Field
DocType
self-sustained activity,leaky integrate-and-fire neurons,balanced random networks,linear stability,spike train irregularity
Asynchronous communication,Population,Linear stability,Bistability,Synapse,Neuroscience,Premovement neuronal activity,Stable states,Computer science,Bifurcation
Journal
Volume
ISSN
Citations 
8
1662-5188
9
PageRank 
References 
Authors
0.63
14
6
Name
Order
Citations
PageRank
B Kriener1745.41
Håkon Enger290.63
Tom Tetzlaff318615.54
Hans Ekkehard Plesser41559.51
Marc-oliver Gewaltig548340.35
Gaute T. Einevoll620926.15