CORTICOFUGAL MODULATION OF TIME-DOMAIN PROCESSING OF BIOSONAR INFORMATION IN BATS

The Jamaican mustached bar has delay-tuned neurons in the inferior col liculus, medial geniculate body, and auditory cortex. The responses of these neurons to an echo are facilitated by a biosonar pulse emitted by the bat when the echo returns with a particular delay from a target located at a particular distance. Electrical stimulation of cortical delay-tuned neurons increases the delay-tuned responses of collicular neurons tuned to the same echo delay as the cortical neurons and decre ases those of collicular neurons tuned to different echo delays, Corti cal neurons improve information processing in the inferior colliculus by way of the corticocollicular projection.