Abstract
Spatio-temporal filter theory is applied, on the basis of the describing function method, to anidealized nonlinear neuronal circuit of recurrently inhibited layer structure offering a model of synchronous neuronal activities in the brain.
The filter theory suggests that the system dynamics is fundamentally determined by the Fourier transform of the spatio-temporal connection in the system and that the increase in connection weight and feedback delay may cause synchronous oscillation.
The describing function for two sinusoids plus bias input reveals the competition among spatio-temporal dynamic modes such as synchronous oscillation, spatial waves, etc
Computer simulation as well as the describing function analysis shows that abrupt mode transition occurs between a spatial wave and synchronous oscillation with either internal parameter changes or appropriate external inputs.
These competitive relations among dynamic modes suggest possible connection with sudden mode transitions in EEG or in epilepsy.
