Nonlinear analysis of spatio-temporal receptive fields: II Dynamic properties of Vl simple cells

摘要

I apply a recently developed approximation method to two standard models for orientation tuning: a one-layer model with difference-of-Gaussians connectivity and a two-layer excittatory- inhibitory network. Both models reveal identical steady states and instabilities to high firing rates. The two-field model can also loose stability through a Hopf-bifurcation that results in rhythmically modulated tuning widths around 0-50 Hz. The network behavior is almost inde- pendent of the relative weights and widths of the kernels from excitatory to inhibitory cells and back. Formulas for tuning properties, instabilities, and oscillation frequencies are given.