The mechanism whereby hormones exert their feedback effects as well as the behavioral abnormalities seen in many endocrine diseases have been clarified by the demonstration of hormone receptors in specific brain areas and by selective modification of neurotransmitter content and turnover induced by different hormones. On the other hand a large number of studies have unraveled the nature of the neuroanatomic pathways and of many neurotransmitters that impinge upon the neurosecretory cells controlling, through the hypothalamic hormones, pituitary secrections; consequently peripheral endocrine changes may reflect brain function and its related disorders. Despite the great amount of knowledge accumulated in the last few years, many aspects of the interrelationship between the central nervous and the endocrine systems in adults are still little understood. This book summarizes reports delivered at a recent workshop at the University of Parma, Italy. In the first part, the psychoneuroendocrine pattern in the so called normally aging brain is described. In the second part, the psychoneuroendocrine pattern is depicted for the most stressfull expressions of pathological aging like the Alzheimer type, multi-infarct dementia, Parkinson's disease, depression and memory impairments. Furthermore, the possibility of using endocrine patterns as a biological marker of the pathologically aging brain is suggested. These reports lay the basis for new proposals in the pathogenesis of aging and for new endocrine approaches in the prevention and treatment of aging impairments.