The degree of hand preference and hand performance on bimanual tasks in right- and left-handers

Abstract

A complete understanding of the principles behind bimanual handedness is currently lacking, and variability has frequently been attempted minimised. The goal of this study was to study the variability in bimanual handedness. The first aim was to examine right-and left-handers unimanual and bimanual hand preferences by using a questionnaire constructed for the purpose of the study, consisting of a modified version of the Edinburgh Handedness Inventory and several bimanual items. The results showed that the right-handers had a stronger preference for their preferred than the left-handers. The second aim was to explore betweenhand performance differences, using five fine motor tasks. Both right- and left-handers were found to have better performance with their preferred hand. The right-handers had more between-hand performance differences than the left-handers. The last aim was to examine the relationship between bimanual hand preferences and bimanual hand performance. The results indicate a positive significant correlation between BI preferences and performance in bimanual fine motor tasks. The more strongly lateralised subjects show larger between-hand differences, as indicated by higher BI values. The results support the notion that what you get depends on how you measure it, and suggest that there is larger variability in hand preference and performance than previously indicated.