Ageing as a result of the psychophysiological interaction during the life-span? A theoretical model

The variations in functional capacity, life quality and health increase as people grow older. Most likely, this is the result of a lifelong process in which both "wear-and-tear" and constructive development play a major role. Life experiences all the way from daily hazards to burdensome life events, to long-term exposure, to stress and strain might wear out the body. Life experiences of self-fulfillment, self-realization, sense of coherence, social support and life-span quality might, on the other hand, promote the constructive development toward successful ageing. The dynamic balance between those processes over the lifetime are assumed to explain the variations in functional capacity in old age. The physiological expressions of those experiences are found in the concept, allostatic load, which refers to the toll exacted on the body through attempts to adapt. The mechanisms tying the experience to the ageing processes are thought to be psychoneuroendocrinological reactivity, primarily in the HPA-axis system. The psychophysiological models suggested here would state that the higher the allostatic load, presently and during the life span, the more likely there will be a reduction in functional capacity in old age, accelerating the ageing process to a state of premature ageing. Retrospective life-span research on autobiographic recapitulation, coping and reminiscing of Ericksonian stage solutions seems to support such a model. Personality factors, genetic or acquired vulnerability for pathogenic factors and sensitivity for salutogenic factors seem to have a modifying or predisposing role. (C) 2002 Elsevier Science B.V. All rights reserved.