Associative priming in Pavlovian conditioning.

Any occasion on which an animal is placed in an experimental setting or context and receives pairings of one event with another provides the opportunity for a variety of associative structures to be acquired. These structures range from simple associations, which allow the presentation of one event to activate or prime a memory of the other, to hierarchical associations, which allow a simple association to be primed by some other event (e.g. the context in which the simple association was acquired). Experiments with rats that reveal priming effects consistent with both of these putative associative structures are reviewed.