THE INFLUENCE OF AGE ON MANUAL ASYMMETRIES IN MOVEMENT PREPARATION AND EXECUTION

An experiment was conducted to examine the influence of age on the exp ression of manual asymmetries in movement preparation and execution an d the implication toward the hypothesis of differential hemispheric ag ing. Young, middle age, and elderly subjects performed a simple pointi ng task under a precuing paradigm (Rosenbaum, 1980). Although elderly subjects were slower in initiating and completing their movements comp ared to younger subjects, they demonstrated the same right-hand advant age for the speed of movement execution and exhibited the same left-ha nd advantage for speed of preparation as the younger subjects. These r esults indicate that elderly subjects exhibit the same pattern of manu al asymmetry as younger subjects. Futhermore, elderly subjects exhibit ed a more pronounced left-hand advantage than younger subjects for mov ement preparation. This finding is not consistent with the idea that r ight-hemisphere visuospatial function deteriorates more rapidly with a ge.