Encoding of stimulus movement parameters in the cat visual system.

Analysis of matrixes consisting of the numbers of spikes evoked by the movement of simple and complex stimuli in cat visual cortex neurons by the principal components method demonstrated vector encoding. The responses of direction detectors to the movement of points and orientation detectors to changes in the angle of a line were encoded independently in areas V1 and V2 of the cortex. Each type of detector was represented by excitation of two cardinal neurons generating sine and cosine functions. The responses of neurons in the associative cortex with selectivity for the direction of movement of specifically oriented bars depended on four cardinal neurons formed by summation of the excitations of the cardinal neurons of the directional and orientational channels.