Developmental trends in voluntary selective attention: Differential effects of source distinctness

The study is designed to test the hypothesis that an inability to separate incoming information into discrete messages is a source of young children's relatively poor performance in selective attention tasks. Accordingly, the experiment arranges three conditions of varying distinctness between central and distractor information. The central task consists of a continuous matching task in which the subject is required to track the position of a stick figure. Rate of presentation is manipulable. The effects of the three different distractor types are assessed on individually determined and matched baselines of performance on the central task in the absence of distraction. Kindergarteners, second graders, and fifth graders serve as subjects. Whereas second-grade and fifth-grade children are most accurate when the distinctness of the messages is high, the opposite pattern occurs in kindergarteners. This interaction implicates strategy differences that are age-related. Kindergarteners perform as if the task requires divided attention. Second graders and older children use the more appropriate focusing strategy, but the former have particular difficulty when the messages are not distinct. Equally notable is the second graders' success in focusing when the source discreteness is arranged. The relation between this result and previous reports is also discussed.