Age and information processing: event-related potential studies

This paper reviews our recent studies on the effects of aging on human information processing. In these studies the event-related potentials of the brain (ERPs) recorded in visual discrimination tasks were compared in younger and older groups of subjects in four experiments. We obtained a slight age-related delay of the NA component of the ERP. This component is a correlate of elementary pattern-identification processes. Obvious latency differences appeared on the anterior positivity, selection negativity, and N2b components in tasks where the target stimuli were defined by two stimulus characteristics. These components are correlates of attentional processes, i.e., the results support the view emphasizing age-related decline of the attentional processes. In the elderly the late positivity was less sensitive to stimulus probability, and in the older groups this component was more evenly distributed over the scalp. These results are considered as an indication that the structure of stimulus sequences was less efficiently represented in the older subjects