EN
Visual responses of single units in the superficial layers of the superior colliculus were examined in <cats> with pretrigeminal brainstem transections and lesions in the contralateral superior colliculus. The percentage of direction selective cells was decreased in lesioned as compared to non-lesioned cats. This effect may be a result of the elimination of suppression from the contralateral superior colliculus as well as disturbance of the projections from other structures of the contralateral hemisphere.