Posture and target location effects on manual preference

Twenty-nine light-handed participants made unimanual movements to 5 target locations while standing and while balancing on a rocker platform. Manual p reference was affected by targets location (p < .001; manual preference ten ded to be concordant with target hemispace) and posture (p < .05; responses from the rocker platform were associated with a lower level of light-hand responding). A location by posture interaction (p < .05) indicated that the effect of posture was present only for targets in left hemispace; the righ t hand was used less frequently in the rocker condition than simple standin g. Manual preference is viewed as a process of response selection motivated by an effort to minimize neural processing and mechanical costs. (C) 2000 Academic Press.