EFFECTS OF SENSORY ISOLATION UPON APPETITIVE, AVERSIVE, AND NEUTRAL INTRACRANIAL SELF-STIMULATION IN THE RAT

Previous studies have indicated that intracranial shock can have reinforcing properties. These studies, however, have either used subjects outside sensory isolation, or have used intracranial brain stimulationof the rat in only an appetitive or "pleasure" center. The present research attempted to investigate the effects of : (1) appetitive electrode placement in the rat's brain ; (2) aversive electrode placement ; (3) neutral electrode placement, and (4) brain stimula-tion and no-stimulation conditions both inside and outside sensory isolation. The results indicated a significantly higher rate of responding as well as a significantly longer response time in the sensory isolation condition with brain stimulation available for rats with electrode placement in the appetitive and aversive brain centers. Significant differences were also found for performances inside and outside sensory isolation concerning stimulation and no-simulation effects, electrode placement, and sequential effects.