Stress, hypothalamic function and neuroendocrine consequences.

The physiology of the emotional response patterns to "stressful" psychosocial stimuli is surveyed. These limbic-hypothalamic patterns are basically designed to protect the individual and species from adverse environmental influences in primitive life. Their expressions always form a triad, with a situation-specific "somatomotor"-behavioural link, a "visceromotor"-autonomic and a hormonal link, the latter two adjusting inner organs, metabolism, water-salt balance, etc., to provide optimal support to the behavioural expression. Because of their uniformity throughout species, animal experiments have greatly contributed to our understanding of how these responses may also importantly contribute to common disorders in modern society, at least when intensely and/or commonly evoked. Thanks to our more advanced neocortex, man differs here from animals mainly in two ways. First, we learn to cope with some environmental stimuli and thus delimit undue emotional engagements; second, when once elicited we can often suppress the behavioural link, when this is socially appropriate. As we cannot suppress the autonomic-hormonal links, however, they then occur more or less "in vain", and such socially enforced dissociations of per se normal response patterns may not in the long run be healthy. Finally, the better known among these differentiated responses are briefly outlined, with particular emphasis on the potentially most important ones, the "defence reaction" and the "defeat reaction".