Thresholds of response to electric shock in previously undernourished rats

Abstract

1. Rats were undernourished in early life by feeding their mothers a restricted quantity of a good-quality diet during pregnancy and lactation. All offspring were fed ad lib. from weaning. Behavioural tests were done using adult males.2. Thresholds of aversion to electric shock were determined in a rectangular box, one side of which was designated ‘live’ and the other ‘safe’ (o V side) for any particular shock level. Three 15 min sessions were given at each of five shock levels. Previously undernourished rats had a lower aversion threshold than controls. They spent more time than controls on the o V side at two intermediate levels of shock.3. Other male rats were subjected to six graded series of brief, unavoidable shocks. Previously undernourished rats responded to a greater total number of shocks than controls.4. These results support the hypothesis that previously undernourished rats have a lowered threshold of arousal.