Citation

Viviani P, Schneider R. J. Exp. Psychol. Hum. Percept. Perform. 1991; 17(1): 198-218.

Affiliation

Faculty of Psychology and Educational Sciences, University of Geneva, Switzerland.

Copyright

(Copyright © 1991, American Psychological Association)

DOI

unavailable

PMID

1826312

Abstract

Trajectory and kinematics of drawing movements are mutually constrained by functional relationships that reduce the degrees of freedom of the hand-arm system. Previous investigations of these relationships are extended here by considering their development in children between 5 and 12 years of age. Performances in a simple motor task--the continuous tracing of elliptic trajectories--demonstrate that both the phenomenon of isochrony (increase of the average movement velocity with the linear extent of the trajectory) and the so-called two-thirds power law (relation between tangential velocity and curvature) are qualitatively present already at the age of 5. The quantitative aspects of these regularities evolve with age, however, and steady-state adult performance is not attained even by the oldest children. The power-law formalism developed in previous reports is generalized to encompass these developmental aspects of the control of movement.

Language: en