Table of Contents Author Guidelines Submit a Manuscript
TheScientificWorldJOURNAL
Volume 6, Pages 1805-1809
http://dx.doi.org/10.1100/tsw.2006.291
Short Communication

Interlimb Transfer of Grasp Orientation is Asymmetrical

1Département de Kinanthropologie, Université Québec á Montréal, Québec, Canada
2Institut de Réaptation de Montréal, CRIR Université Montréal, Québec, Canada
3Memory and Motor Skills, Disorders Research Centre, Clinique Sainte Anne, Québec, Canada

Received 27 July 2006; Revised 9 December 2006; Accepted 11 December 2006

Copyright © 2006 Victor Frak et al.

Abstract

One the most fundamental aspects of the human motor system is the hemispheric asymmetry seen in behavioral specialization. Hemispheric dominance can be inferred by a contralateral hand preference in grasping. Few studies have considered grasp orientation in the context of manual lateralization and none has looked at grasp orientation with natural prehension. Thirty right-handed adults performed precision grasps of a cylinder using the thumb and index fingers, and the opposition axis (OA) was defined as the line connecting these two contact points on the cylinder. Subjects made ten consecutive grasps with one hand (primary hand movements) followed by ten grasps with the other hand (trailing movements). Differences between primary and trailing grasps revealed that each hemisphere is capable of programming the orientation of the OA and that primary movements with the right hand significantly influenced OA orientation of the trailing left hand. These results extend the hemispheric dominance of the left hemisphere to the final positions of fingers during prehension.