Instantaneous non-linear processing by pulse-coupled threshold units.
Contemporary theory of spiking neuronal networks is based on the linear response of the integrate-and-fire neuron model derived in the diffusion limit. We find that for non-zero synaptic weights, the response to transient inputs differs qualitatively from this approximation. The response is instantaneous rather than exhibiting low-pass characteristics, non-linearly dependent on the input amplitude, asymmetric for excitation and inhibition, and is promoted by a characteristic level of synaptic background noise. We show that at threshold the probability density of the potential drops to zero within the range of one synaptic weight and explain how this shapes the response. The novel mechanism is exhibited on the network level and is a generic property of pulse-coupled networks of threshold units.
Helias
Moritz
M
RIKEN Brain Science Institute, Wako City, Japan. helias@brain.riken.jp
Deger
Moritz
M
Rotter
Stefan
S
Diesmann
Markus
M
D000200:Action Potentials / Q000502:physiology; D000465:Algorithms; D000818:Animals; D019295:Computational Biology / Q000379:methods*; D003198:Computer Simulation; D008959:Models, Neurological; D009415:Nerve Net / Q000502:physiology*; D017711:Nonlinear Dynamics; D016011:Normal Distribution; D013569:Synapses / Q000502:physiology