Fine motor skill performance in left- and right-handers: Evidence of an advantage for left-handers.

A total of 22 right-handed and 22 left-handed participants performed tasks on a well-established test of manual dexterity in addition to completing the Waterloo Handedness Questionnaire. Analysis of Variance revealed that left-handers performed significantly better on the Purdue pegboard test when the task relied on the co-ordination of both the left and right hands. Multiple regression analysis indicated that the Purdue pegboard assembly task is a predictor of self-reported hand preference and of handedness when classified by the Waterloo Handedness Questionnaire. Left-handers showed a smaller performance difference between hands, suggesting an advantage in using their non-preferred hand, although this did not lead to a better performance on a bimanual placement task. These results suggest that left-handers perform more proficiently when hand actions have to be alternated in completing a task. The superior performance of the non-preferred hand in left-handers might be explored to develop future behavioural predictors of handedness.