Manual asymmetries in reaching movement control. II: Study of left-handers.

Two experiments performed with left-handed subjects investigated how the manual asymmetries and hemispheric specialization involved in visuo-manual coordination are associated with handedness. Pro and retroactive processes involved in rapid movement control were analyzed according to the different movement parameters to be controlled, similar to studies performed with right-handers (Boulinguez, Nougier and Velay, 2001). Manual performances and kinematic properties of reaching movements showed that the left and right hands of left-handers behaved in the same way as the left and right hands of right-handers. Results are discussed in the light of the independence of handedness and other forms of cerebral dominance in sensori-motor information processing involved in hand movements.