Adult age differences in visual search as a function of stimulus mapping and processing load.

Previous research has indicated age-related declines in visual search and memory search performance. Recent nondevelopmental evidence suggests that after extensive practice with a consistent stimulus set, performance in search tasks becomes independent of information load. Eight volume (mean age 23.55 years) and eight elderly (mean age 74.92 years) females searched for either two or four target letters which appeared individually in displays of one, four, or nine letters using either an unchanging memory set (consistent mapping) or changing memory sets (varied mapping); subjects performed over six sessions. Under the varied mapping condition the traditional pattern of age-associated decrement in search was obtained, while in the consistent mapping condition adult age differences were attenuated. These findings supported the hypothesis that age-related decrements in visual search can be eliminated, or at least minimized, when various control processes such as selective attention are short-circulated by automatic information processing.