A bimanual circle drawing task was used to investigate the influence of manual dominance and attentional direction on interlimb coordination. 10 right-handed, 10 left-handed and 10 ambidextrous participants, were required to perform bimanual circling movements in symmetrical (inwards) and asymmetrical (anti-clockwise) coordination modes. The participants were required to visually attend to either the right hand, the left hand, or to a neutral point. Movements were paced with an auditory metronome at two predetermined frequencies corresponding to (a) the critical frequency, where movements in the asymmetrical mode were unstable but before movement reversals occurred, and to (b) a frequency two-thirds of this, where movements in both coordination modes were stable.
Measures of aspect ratio (degree of circularity) and Relative Tangential Angle (RTA) were inspected to determine the differences in temporal asynchrony and spatial accuracy for each group. Overall, when visual attention was directed toward a neutral point, the symmetrical pattern was performed more easily than the asymmetrical pattern, with frequency increases leading to performance decrements. Right-handers showed the largest effect of hand dominance, whereas left-handers and ambidexters demonstrated no significant differences in the performance of their hands.
Findings are discussed in terms of differences in hemispheric organisation and cognitive factors such as the allocation of attention. Further analysis is currently in progress to investigate the influence of the manipulation of visual attention on the bimanual circle drawing task.