Learning where to look: Electrophysiological and behavioral indices of visual search in young and old subjects.

Explored 24 young (aged 18-24 yrs) and 24 elderly (aged 65-75 yrs) right-handed males' use of regularities in target location in a visual display to guide searching for targets. Although both young and elderly Ss showed efficient use of search strategies, slight differences in reaction times suggest decreased ability in elderly Ss' use of complex cues. In young Ss, P3 amplitudes were larger for trials where the rule that governed the location of the target became evident. Enhanced slow wave (SW) amplitude indicated uncertainty in random search conditions. Elderly Ss' P3 and SW amplitudes, however, seemed unrelated to behavioral performance. Results suggest that age-related differences in search tasks can be understood in terms of age-related changes in strategies of allocating visual attention