ABSTRACT
Development proceeds as a constant interaction between environmental and genetic factors. These gene-environment interactions result not only in growth, but also in adaptation; long-term changes occur as a result of environmental influences. The early environment influences development in part through the “programming” of neuroendocrine systems. In the rat, naturally occurring variations in maternal care regulate the development of hypothalamic-pituitary-adrenal (HPA) responses to stress in the pups. The critical targets are the corticotropin-releasing factor (CRF) systems of the hypothalamus and amygdala. The effects of early maternal care result in enduring changes in behavior and physiology of adult offspring, and the alterations are in some cases transmitted across generations.
