Determinants of visual search performance: age and practice effects

In the present experiment, ability-performance relationships were used to assess changes in task requirements across practice. A variety of cognitive and speed ability measures were administered to each subject to measure the following factors: general, fluid, and crystallized intelligence; working memory; perceptual speed; semantic memory access speed; and psychomotor speed. Subsequently, ability-performance relationships were investigated across extensive practice on consistently mapped (CM) and variably mapped (VM) versions of a semantic category visual search task for young (17-30) and old (66-80) adults. The ability-performance relationships revealed similar patterns across CM and VM practice for both age groups. Namely, initial performance was predicted by general ability and semantic memory access, whereas later performance was predicted by perceptual speed. Thus although the mean data suggested that only the young adults had developed an automatic attention response in the CM condition, the locus of the differences between CM and VM or between age groups could not be localized through the ability-performance relationships. Only through a transfer manipulation designed to assess the automaticity of the response in the CM condition did we observe strikingly different ability-performance relationships for the young adults relative to the old adults.