An Examination of Change in Control of the Right and the Left Hand Across the Lifespan

Abstract

This study examined changes in manual asymmetry across the lifespan using the Purdue pegboard protocol. One hundred and four right-handed individuals were recruited and separated by age decade. Individuals placed pegs into holes as fast as possible in 30 s using the right hand, left hand, and both hands simultaneously. Movements with the right hand were significantly faster than the left hand and for both hands for all age groups. The number of pegs successfully inserted into the holes significantly declined in the sixth decade, and this result was observed for both the right and left hands. No significant differences between the decades were observed with respect to the computed laterality quotient; thus, declines in manual asymmetry with age were not observed. It is suggested that the performance speed declines with age are likely to be due to central factors. Better performance of the right versus left hand across the lifespan supports the right hemi-aging model, and may also be due to practice, the differential roles of the right versus the left hand, and the task itself.