Most individuals are either left- or right-handed. How the skills they have learned from the dominant arm (or hand) are transferred to the non-dominant arm have long intrigued physiologists and neurologists.
The transfer of a skill learned in one hand to the other hand has been used as evidence for the role of the brain's hemispheres in controlling that skill. The movement of knowledge from the dominant to the nondominant arm (D ND) has been interpreted as confirmation of the brain's ability to encode an experience in the dominant hemisphere with the dominant hand and to influence the performance of the nondominant hand. Many researchers believe that this process is accomplished either through connections across both hemispheres or through the same side of the brain. Other scientists believe that transfer in the opposite direction reflects a dominance of the right hemisphere (in right-handers) for some aspects of motor control, so both directions of transfer can be explained with a single model.
Little is known about the involvement of the body's subcortical structures (such as the cerebellum, and spinal cord) in this process. While it is possible to get some indication of the role of the cerebral hemispheres through the study of subjects with a sectioned corpus callosum, this has rarely been pursued in the case of motor learning and transfer. Accordingly, a team of researchers wondered whether learning a force field with one arm generalizes to the other arm.
Previous observations have found that since learning generalizes in a muscle-like, intrinsic coordinate system
Contact: Donna Krupa
American Physiological Society