EFFECTS OF ACUTE SHOCK ON BODY-WEIGHT ARE MEDIATED BY CHANGES IN FOOD-INTAKE

We examined the causal role of decreased food intake in the body weigh t pattern observed after exposure to intermittent footshock. In Experi ment 1, relative to controls, shocked animals decreased food intake an d lost weight in the 24-h test. An unshocked group whose food intake w as yoked to the shocked group (food-yoked group) for the poststress pe riod revealed that food intake was a sufficient cause of the body weig ht loss. In Experiment 2, after the first 24 h, the shock group recove red food intake and body weight gain but did not compensate for the in itial losses. Body weights of food-yoked animals again indicated that food intake was a sufficient cause of these effects. The lowered body weight of shocked animals at the end of testing was due to a transient hypoingestion and a failure to subsequently show a compensatory hyper ingestion. Dess's (1991) regulatory shift hypothesis is refined in the light of these findings.