EFFECTS OF EARLY EXPERIENCE ON ADRENOCORTICAL REACTIVITY

Unmanipulated control animals and rats that were exposed to handling or electric shock either pre- or post-weaning were subsequently stimulated by being placed into a novel environment for 5 sec or 3 min. Plasma corticosterone levels were sampled 5, 15, or 30 min following the cessation of this stimulation and in animals that received no such stimulation. The handled and shocked animals did not differ. As a group, however, the corticosterone response of the manipulated animals showed them to be less reactive than controls irrespective of the duration of stimulation. © 1969.