IS THE AGE-COMPLEXITY EFFECT MEDIATED BY REDUCTIONS IN A GENERAL PROCESSING RESOURCE

The rate of information processing, as revealed in measures of reactio n time, slows with advancing age and this slowing is most evident as p rocessing complexity increases. This phenomenon, known as the Age-Comp lexity effect, has been attributed to general changes in the speed of processing that affect all components of processing indiscriminantly, both within and across tasks in a particular processing domain. That t he slowing is thought to be task- and process-independent has led to t he additional inference that it reflects reductions in a general proce ssing resource. On the basis of converging evidence identified in a re view of both behavioral and chronopsychophysiological studies, we argu e that the slowing induced by older age is not generalized, but rather is both task-dependent and process-specific and, as such, cannot be e xplained in terms of a diminished general processing resource. We clos e by speculating that elements of the age-induced slowing can be inter preted within the context of the cognitive-energetical model. (C) 1997 Elsevier Science B.V.