The inhibitory components in the responses of the lateral suprasylvian area neurons to moving stimuli in cats.

The inhibitory components in the neuronal responses of the cat's lateral suprasylvian area (LSA) to moving bright and dark stimuli were investigated. The LSA neurons could be divided into two groups. Neurons of the first group (33%) do not reveal spatial displacement of the inhibitory zones and show displacement of the discharge centers in the receptive field only for one polarity of contrast of moving stimuli, either brighter or darker than the background. The second group (67%) contained the neurons which showed a spatial displacement of the inhibitory components and discharge centers in the receptive field for either polarity of contrasts of the moving stimuli. Tested with stationary flashing stimuli, the majority of neurons in both groups had overlapping ON-OFF discharge regions within their receptive fields. The results obtained with moving stimuli of different speeds and with the masking method suggest the rebound origin of the inhibitory responses in LSA neurons.