Aging as intracohort differentiation: Accentuation,the Matthew effect,and the life course

Recent contributions of sociologists and others have brought a new awareness and new theoretical understanding of the extent to which human aging and life-course patterns are shaped by social conditions and influenced by social change. Yet the potential of many social processes to account for individual aging patterns remains untapped, because research and theory have focused heavily upon comparisons between cohorts rather than the internal differentiation of cohorts. This paper shows that focusing upon intracohort differentiation over the life course leads to a mobilization of sociological findings whose age-related implications have not been exploited. Using the phenomenon of aged heterogeneity as an illustrative case, it is suggested that intracohort differentiation—operating through macro-level, organizational, and micro-level processes—can explain significant phenomena of aging previously neglected by theory, or else assumed to be psychological in origin. These processes specify Merton's Matthew effect. Implications for biological aging and for research are briefly discussed.