Movement Time, Movement Distance, and Movement Accuracy: A Reply to Newell, Carlton and Kim

Abstract

Several concerns with the article by Newell, L. G. Carlton, and Kim (1994) are raised, including the interpretation of ratio scores in the measurement of movement error in rapid limb action. The authors are correct that, in detail, their data contradict the predictions from impulse-variability theory. But, when viewed in a larger perspective, their data suggest that the overwhelming determiner of timing error is movement time (not movement amplitude), and the primary determiner of spatial error is movement amplitude (not move- ment time)-which at least approximates some of the predictions from im- pulse-variability theory. Additional comments are made on the implications for the space-time view of Hancock and Newel1 (1985).