Arousal Effects on Evoked Activity in a "Nonsensory" System

Abstract

Responses from motor cortex evoked by cerebellar stimulation have been recorded with chronically implanted electrodes from cats in different states of arousal. The response, which in the waking cat consists of a short latency biphasic component followed by one or more slower waves, was attenuated, or abolished completely, in association with electroencephalographic and behavioral signs of decreased arousal. In contrast, responses in primary somatosensory cortex evoked by stimulating the bulbar trigeminal nucleus were enhanced during periods of decreased alertness.