The expression of manual asymmetries following extensive training of the nondominant hand: a kinematic perspective.

A single experiment involving 5600 discrete aiming trials with the left hand and 560 trials with the right hand designed to track the kinematic changes associated with left hand practice is reported. In general, performance data revealed that following practice movement time of the left hand achieved a level of performance similar to that of the right. However, the kinematic variables analyzed were instructive in identifying differential control processes associated with the right and left hand. Specifically, the right hand was more accurate during the ballistic phase of movement execution, while practice enabled the left hand to utilize response-produced feedback more efficiently.