Relevant stimuli and auditory evoked potentials

Four cats, classically conditioned to a flashing light paired with food reinforcement, were tested for amplitude changes of click-evoked potentials during increasing hours of deprivation. Signal averaged evoked potentials from the auditory cortex, cochlear nucleus, and round window electrodes showed no significant changes in amplitude, but significant changes were found in the variance as food deprivation increased. Such changes are more consistent with expected changes in the CNS than the amplitude changes of the auditory cortex found by Saunders and Chabora.