Velocity as a Factor in Movement Timing Accuracy

Abstract

Our experiments examined the boundaries within which movement timing error decreases in timing responses as a function of increases in movement velocity. Experiment 1 investigated the lower end of the movement-velocity continuum and showed a curvilinear decrease in movement error as average velocity increased from 5 to 25 cm/sec. Experiment 2 also revealed a decrease in movement error as velocities increased from 67 to 95% (98-320 cm/sec) of maximum velocity for the amplitudes employed. These findings were confirmed in Experiment 3 which examined the full range of the velocity continuum in a completely within-subject design. Absolute timing error, expressed as a percentage of movement time, was a logarithmic function of average velocity, with error decreasing as velocity increased. Overall, the findings demonstrate the generalizability of the movement-velocity effect on timing error. The discussion focuses on explanations for this phenomenon which currently appear far from clear-cut.