Dependence of Manual Grasping on the Behavioral Context: A Comparison between Arms and between Age Groups

Abstract

We evaluated the kinematics and dynamics of grasping in a typical laboratory situation (L) and in a more everyday-like situation (E), using right-handed subjects. Performance was compared when young subjects used their right versus left arm, and when young versus old subjects used their left arm. As in our previous work, multiple differences emerged between parameter values in the two contexts, L and E. These context differences were, however, more pronounced for the left rather than for the right arm of young subjects, and more pronounced for the left arm of young rather than older subjects. We propose an explanation based on the differential involvement of the dorsal and ventral cortical processing stream in L and in E: The differential involvement would be accentuated for the left arm of young, but not for the left arm of older subjects .