Published in Neurocomputing, vol.38--40 pp. 1461--1467, Jun 2001.
We present a dynamic normalization model to represent both the transient and the steady state components of V1 simple and complex cell responses. Primary receptive field properties are chiefly determined by the convergence of LGN afferents. These linear responses are rectified, and subjected to shunting inhibition through cortical feedback, which accounts for the non-linear characteristics of the neuronal responses. The duration of the transient response is determined by the time delay and the low-pass filtering of the cortical feedback. In addition to accounting for basic nonlinear behaviors such as response saturation and cross-orientation inhibition, the model is also able to reproduce several short-term contrast and pattern-selective adaptation effects.