The response patterns of collicular neurons to moving stimuli in cats after lesion of the visual cortex

The speed and direction selectivity of responses of collicular neurons in pretrigeminal cats following lesions of the visual cortex were examined using moving light spots. Following cortical lesions the number of cells showing direction selectivity was reduced, but the number of cells showing speed selectivity was increased. It is suggested that some of the characteristics of collicular neurons are dependent on initial organization of the intracollicular synaptic connections rather than the corticocollicular ones.