The use of focused attention in visual search by young and old adults.

A deficit in focused attention has recently been suggested to underlie some of the cognitive decrements seen in the elderly. This hypothesis was tested in two visual search studies. Subjects had to decide whether or not a given target was present among an array of six digits, three of which were red, the rest black. For the "yes" trials, prior information regarding target color substantially reduced search time in comparison to warning signal that did not provide color information. This reduction in search time was equivalent in the young and the old, both at long (ad lib) and shorter (250-1000 msec) array durations. This result suggests that both age groups are equally proficient in focusing their attention on the digits of the relevant color. On the "no" trials, prior color-information was not effective in reducing search time. There was some evidence in experiment two that the older subjects were using a different search strategy on these trials.