This paper summarizes the effects of various early environmental manipulations (infantile
handling, maternal separation, neonatal immune challenge) on the development of
hypothalamic-pituitary-adrenal (HPA) responses to stressful stimuli. Each manipulation
results in a permanent effect on HPA responsivity to stress, although the effects qualitatively
are quite different. In each case the effects are apparent in terms of different levels of activity
of the corticotrophin-releasing hormone/arginine vasopressin neurons in the paraventricular …