EFFECTS OF Co ON ELECTRICAL SELF-STIMULATION OF THE BRAIN AND BLOOD PRESSURE

摘要

The effects of 1000 and 2000 rad 60Co on electrical self-stimulation of subcortical brain areas and blood pressure were investigated to determine whether radiation-induced performance decrement occurs in a like manner for a positiviely-rewarded behavioral task as it does for the more typically studied shock-avoidance task. During the early postradiation minutes self-stimulation responses decreased or ceased and resumed shortly thereafter, revealing a similar course of performance decrement as seen with shock-avoidance, discrimination tasks. Early postradiation hypotension with subsequent recovery paralleled the performance decrement, reproducing the blood pressure-behavior correlations seen previously with shock reinforcement. The blood pressure elevating influence of the brain stimulation observed prior to irradiation was diminished or absent during the deep hypotensive stage postradiation, but tended to return minutes later.