Age, handedness, and sex contribute to fine motor behavior in children.

The original rotor pursuit test requires that the subject attempts to keep a metal stylus in contact with a small metal disk that was placed in the surface of a turntable that rotated at a constant speed. The present study evaluated the Psychology Experiment Building Language (PEBL) pursuit rotor task. Children (N=427, ages 9-13, 44.4% females) completed a handedness inventory followed by four pursuit rotor trials with each hand. The total time on target increased with age with the dominant as well as non-dominant hands. A small, but significant, sex difference favoring males was also observed. Dextrals spent more time on target than sinistrals with their dominant hand but the reverse pattern was observed for the non-dominant hand. These group differences were independent of prior computer experience. These findings indicate that the freely downloadable PEBL pursuit rotor task is a useful measure of psychomotor function (http://pebl.sf.net) in children and adolescents.