Disinhibition as a mechanism for visual cortex neurons to tune to cross-shaped figures.

A discrete simulation model of a receptive field selectively responding to cross-shaped figures, as seen in 40% of primary visual cortex neurons in the cat, was studied. The model was based on disinhibition of end-stop inhibition in the receptive field by the lateral disinhibition zone. These experiments showed that this mechanism can produce selective or, conversely, invariant tuning to the shape and orientation of cross-shaped figures and could underlie the high sensitivity of neurons to second-order image features.