Shadowing and target detection as a function of age: Implications for the role of processing resources in competing tasks and in general intelligence

Abstract

This experiment employed a selective attention task which required reading aloud a verbal passage from a computer screen (shadowing) and simultaneous detection of target words in a prose passage presented aurally via earphones. Use of two types of passages requiring different amounts of processing for successful shadowing and two classes of targets requiring different amounts of processing for detection produced four experimental conditions of varying processing resources load.

Shadowing performance correlated with psychometric tests of Gc, but target detection showed no correlations with measures of intelligence. Neither measure showed correlations with age or performance on cognitive tests of attention, nor with performance on psychometric tests used as competing tasks. There appeared to be no decline in processing resources with age.

The implications of this finding for the hypothesis that the increased importance of processing resources in competing tasks is responsible for their higher correlations with the general factor of intelligence (as compared with their component single tests) are examined. It is concluded that some ability required by competing tasks, other than their increased call on processing capacity, should be sought as the responsible factor in their increased correlation with “g.”