Developmental differences in response processing

Three age groups (kindergartners, fourth graders, and adults) were compared in their processing of response decisions in a two-choice reaction time task. Manipulation of spatial stimulus-response compatibility resulted in age-related differential effects on reaction time performance. For the younger children, selecting the appropriate response for an incompatibly paired stimulus light required proportionately longer processing time than for older subjects. Similar results were not found for performance under varying levels of response discriminability.