Generalization of contextual fear as a function of familiarity: the role of within- and between-context associations.

Three experiments in rats investigated the generalization of conditioned fear from one context (B) to both a preexposed context (A) and a novel context (C). In each experiment, when the conditioning context (B) had been preexposed, there was greater generalization to context A than to context C; but when B was novel at the outset of conditioning this difference between A and C was not observed. The implications of these results for associative treatments of the development of contextual memories are evaluated.