Temporally spaced responding for food in adult rats after undernutrition early in life.
Rats were undernourished during the suckling and early post-weaning periods and were then fed a good quality diet ad libitum from 43 to 300 days when behavioural testing was begun. Male previously undernourished and control rats were tested on three operant conditioning schedules in which low rates of bar-pressing were rewarded with food (differential reinforcement of low rate or DRL schedules). These were DRL 5 sec, DRL 10 sec and DRL 30 sec. On each schedule the response rates of both groups of animals declined over several sessions and their efficiency at obtaining the food rewards increased. However, there were no significant differences between the two groups on either of these measures. This finding indicates that, despite being hyper-responsive in many situations, including some operant conditioning schedules, previously undernourished rats are as capable as controls of withholding responding when necessary.
D000818:Animals; D000833:Animals, Suckling; D001835:Body Weight; D003216:Conditioning, Operant / Q000502:physiology*; D005260:Female; D005502:Food; D006624:Hippocampus / Q000503:physiopathology; D009748:Nutrition Disorders / Q000503:physiopathology*; D051381:Rats; D012055:Reinforcement Schedule; D012201:Reward; D014886:Weaning