Estimation of reach in peripersonal and extrapersonal space: a developmental view.

This study explored the developmental nature of action processing via estimation of reach in peripersonal and extrapersonal space. Children 5 to 11 years of age and adults were tested for estimates of reach to targets presented randomly at seven midline locations. Target distances were scaled to the individual based on absolute maximum reach. While there was no difference between age groups for total error, a significant distinction emerged in reference to space. With children, significantly more error was exhibited in extrapersonal space; no difference was found with adults. The groups did not differ in peripersonal space; however, adults were substantially more accurate with extrapersonal targets. Furthermore, children displayed a greater tendency to overestimate. In essence, these data reveal a body-scaling problem in children in estimating reach in extrapersonal space. Future work should focus on possible developmental differences in use of visual information and state of confidence.