Mental slowing in elderly persons: A cognitive psychophysiological analysis.

In recent attempts to formulate an integrative model of mental slowing in elderly persons, regression analyses have been done in which reaction-time (RT) data from a large number of studies spanning a broad range of speeded decision-making tasks were combined. The results of these meta-analyses were then used to support the conclusion that there is a generalized, proportional decline in mental processing speed among elderly adults that affects all elements of mentation equally. We present a series of similar regression analyses in which both RT and the latency of the P300 component of the event-related brain potential are included. The results of these analyses indicate that there are elements of mental processing that may be slowed additively, not proportionately, in older persons. Furthermore, the results raise some questions about the logic underlying the interpretation of the meta-regression analysis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)