Hand preference and skilled hand performance among individuals with successful rightward conversions of the writing hand

Abstract

Searleman and Porac (2001) studied lateral preference patterns among successfully switched left-hand writers, left-hand writers with no switch pressure history, and left-hand writers who did not switch when pressured. They concluded that left-handers who successfully shift to right-hand writing are following an inherent right-sided lateralisation pattern that they already possess. Searleman and Porac suggested that the neural mechanisms that control lateralisation in the successfully switched individuals are systematically different from those of other groups of left-handers. I examined patterns of skilled and less-skilled hand preference and skilled hand performance in a sample of 394 adults (ages 18–94 years). The sample contained successfully switched left-hand writers, left-handers pressured to shift who remained left-hand writers, left-handers who did not experience shift pressures, and right-handers. Both skilled hand preference and skilled hand performance were shifted towards the right side in successfully switched left-hand writers. This group also displayed mixed patterns of hand preference and skilled hand performance in that they were not as right-sided as “natural” right-handers nor were they as left-sided as the two left-hand writing groups, which did not differ from each other. The experience of being pressured to switch to right-hand writing was not sufficient to shift lateralisation patterns; the pressures must be experienced in the context of an underlying neural control mechanism that is amenable to change as a result of these external influences.

Keywords:

• Hand preference
• Hand preference switch
• Left-hand preference
• Lateralisation

Acknowledgements

This paper is based on a presentation at the meetings of the Psychonomic Society in New Orleans, Louisiana in November 2000, and on a poster presented at the meetings of the Canadian Psychological Association, Hamilton, Ontario in June 2003. These data were collected in Canada when the author was a faculty member at the University of Victoria. The research was supported by grants from the Natural Sciences and Engineering Research Council of Canada and the David and Dorothy Lam Endowment through the University of Victoria Centre on Aging. The contribution of Ingrid Friesen and Vincenza Gruppuso in collection of these data is gratefully acknowledged.