Fokker-Planck approach to the pulse packet propagation in synfire chain.
We applied the Fokker-Planck method to the so-called 'synfire chain' network model and showed how a synchronous population spike (pulse packet) evolves to a narrow pulse packet (width < 1 ms) or fades away, depending on its initial size and width. The results of numerical integration of the Fokker-Planck equation are in good agreement with those of simulations on a network of leaky integrate-and-fire neurons. For a narrow input pulse packet, the integration of the Fokker-Planck equation requires careful numerical treatment. However, we can construct a precise analytical waveform of an output packet, which proves valid for narrow input pulse packets, from the stationary solution to the Fokker-Planck equation and a previously proposed approximate input-output relationship. Our methods enable us also to understand an essential role of the synaptic noise in the evolution, the peculiar temporal evolution of a broader pulse packets, and the irrelevance of the refractory period in determining the waveform of a pulse packet. Furthermore, we elucidate possible functional roles of multiple interactive pulse packets in spatiotemporal information processing, i.e. the association of information and the temporal competition.
Câteau
H
H
Core Research for the Evolutional Science and Technology Program (CREST), JST, Tokyo, Japan. cateau@brain.inf.eng.tamagawa.ac.jp
Fukai
T
T
D000200:Action Potentials / Q000502:physiology*; D000465:Algorithms; D000818:Animals; D002540:Cerebral Cortex / Q000502:physiology*; D006801:Humans; D009415:Nerve Net / Q000502:physiology*; D009433:Neural Inhibition / Q000502:physiology; D016571:Neural Networks, Computer; D009474:Neurons / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology*