Visual evoked potentials in the great apes.

Visual evoked potentials (VEPs) in response to flash stimuli were recorded from occipital and central-scalp electrodes in the chimpanzee and gorilla. The most notable occipital component of the VEP was a surface-positive wave (P90), the latency of which decreased with development. Central scalp responses, apparent only in older animals, included a characteristic long-latency 'vertex wave' (N125-P225). Observed responses are similar to those reported for humans and monkeys, but appear to share more specific features of human VEPs.