Lateralized effects of hand and eye on anticipatory postural adjustments in visually guided aiming movements.

This study investigated hemisphere-specific processing of visually aimed movements and associated postural adjustments while controlling for handedness and eyedness. Eleven right-handed, right-eyed and right-footed healthy adult volunteers performed, from a standing position, an aiming task under two hand (right and left hand) and three visual conditions (binocular vision, right and left eye monocular vision). Centre of pressure (CoP) displacement, hand kinematics and the target's position were synchronously recorded during performance of the aiming task. Analysis revealed a lower RMS error, a later postural adjustment onset and a smaller centre of pressure dispersion when aiming was performed with the dominant right compared to the non-dominant left hand. On the other hand, no differences on either aiming performance or postural adjustments were noted under the three visual conditions. These results suggest a strong handedness and absence of an eyedness effect on the accuracy of aiming and associated postural adjustments.