Chapter 9 Sensory integration in the deep layers of superior colliculus

Abstract

Publisher Summary The intermediate and deep layers of the superior colliculus appear to be critical parts of the neural circuits involved in the location of visual targets in extra personal space. Many neurons in these layers respond not only to visual input but also to input from other sensory systems - in particular, t6 auditory and somatosensory inputs, and also discharge prior to saccadic eye movements. Neuronal responses to auditory and visual targets, presented either together or separately, in alert, trained cats are studied. When the eyes are centered in the orbit, simultaneous visual and auditory stimulation at the same location in space produces substantial facilitation in the majority of intermediate and deep layer neurons. When the eyes are deviated in the orbit, the borders of some but not all, auditory receptive fields shift in the direction of the deviating eye movement. Among neurons responsive to both visual and auditory input, visual receptive fields shift more substantially than do auditory receptive fields. Deviation of the eyes does not affect the animal's ability to locate either visual or auditory targets. These results imply that sensory maps are actively transformed by the movements of organisms.