ONTOGENIC DIFFERENCES IN CONDITIONING TO CONTEXT AND CS AS A FUNCTION OF CONTEXT SALIENCY AND CS-US INTERVAL

A series of experiments examined ontogenetically the effects of context saliency and CS-US interval on the learning of CS-US and context-US associations. Although adult rats generally showed an inverse relationship between CS and context learning that depended upon CS-US interval and context saliency, the opposite relationship held for preweanlings. Consistent with many contemporary learning theories, adult rats expressed CS-context competition in learning about the US. Preweanlings, on the other hand, exhibited potentiated responding to either the context or the CS as a result of strong learning about the other element. These results suggest that adult and infant rats process information in a qualitatively different manner.