Uncontrollable shock proactively increases sensitivity to response-reinforcer independence in rats.
Learned helplessness theory predicts that animals exposed to inescapable shock acquire an expectancy of response-reinforcer independence, which proactively interferes with learning of response-reinforcer dependence. The theory also predicts that this expectancy can increase sensitivity to subsequent instances of response-reinforcer independence. These experiments test the latter prediction in a paradigm that minimizes the confounding effects of shock-induced activity deficits. Rats were trained to respond for food, then given either escapable, inescapable, or no shock. Subsequently, they received two sessions of response-contingent food followed by sessions of noncontingent food deliveries. During this phase, inescapably shocked animals decreased responding faster than did controls. Experiment 2 replicated this finding with a different schedule of food delivery and a procedure that more directly minimized the possibility that the outcome is due to either direct or indirect shock-induced activity changes. These results support the prediction that uncontrollable aversive events can increase an animal's sensitivity to noncontingent response-reinforcer relationships.
D000818:Animals; D001070:Appetitive Behavior; D001245:Association Learning; D003216:Conditioning, Operant; D004597:Electroshock; D005108:Extinction, Psychological; D006380:Helplessness, Learned / Q000523:psychology*; D006801:Humans; D008297:Male; D009042:Motivation; D051381:Rats