Citation

Lai SC, Mayer-Kress G, Newell KM. J. Mot. Behav. 2006; 38(6): 451-466.

Affiliation

Department of Exercise and Health Science, National Taipei College of Nursing, No. 365, Min Te Road, 112 Taipei, Taiwan. lsc2kpsu@yahoo.com.tw

Copyright

(Copyright © 2006, Informa - Taylor and Francis Group)

DOI

10.3200/JMBR.38.6.451-466

PMID

17138529

Abstract

The authors investigated the effects of movement time and movement distance on the information entropy and variability of spatial and temporal error in a discrete aiming movement. In Experiment 1, the authors held movement distance (100 mm) constant and manipulated 11 movement times (300-800 ms) of 8 participants. In Experiment 2, the authors tested 6 movement distances at 2 given movement times (15-60 mm at 300 ms; 40-240 mm at 800 ms) in 8 participants. The variability and entropy for spatial error increased with average movement velocity, whereas the variability and entropy for temporal error decreased as a function of average movement velocity. The common variance between variable error and entropy averaged about 84% and 72% for spatial and temporal errors, respectively, suggesting that the probabilistic approach of entropy reveals features that are not present in the standard deviation index of variability. The findings provide further evidence that information entropy may be a useful single-index representation of variability in the movement speed-accuracy relation.

Language: en