Classical conditioning in newborn rats.

Newborn albino rats were trained according to classical conditioning procedure wih one of four intervals between conditioned and unconditioned stimuli. A vibrotactile stimulus (conditioned stimulus) paired with an electric shock (unconditioned stimulus) was presented to the forelimb 80 times. The results demonstrate that conditioning takes place in newborn rats. However, levels of performance as a function of time intervals between stimuli did not resemble the levels traditionally reported for older animals.