Distinct mechanisms for planning keypress and reaching responses: a developmental study.

This study examined developmental effects in the ability to use precue information for the planning of keypress and reaching responses. Participants from four age groups (7, 9, 13, and 21 year olds) performed a spatial precuing task either by pressing one of four response keys (keypress task) or by reaching directly toward one of the four target locations on the screen (reaching task). Reaction time data revealed striking age differences in the ability to use advance information in the keypress task, not in the reaching task. This dissociation confirms the hypothesis that distinct and separate mechanisms govern the planning of indirect keypress and direct reaching responses.