Hemispheric Interaction in Simple and Complex Tasks: A Study of Interlimb Coordination

Past motor control studies examining interlimb coordination using reaction time (RT) and movement time (MT) tasks have not held the number of effectors constant, introducing an experimental confound. The present study sought to reevaluate the area studying bilateral and unilateral activation of the cerebral hemispheres using ipsilateral and contralateral tasks in a RT/MT study that tested the interhemispheric inhibition hypothesis while holding constant the number of effectors, and to determine if the pattern of results would generalize to a complex task. The data for RT/MT were recorded using a Fastec Imaging camera. The results demonstrated that ipsilateral RT/MT responses were significantly faster than contralateral ones, and that the pattern of results generalized when task complexity increased, with simple RT/MT responses being significantly faster than complex ones. There was no interaction between laterality and response. The pattern of results was consistent with the inhibition hypothesis. Future studies examining similar phenomena may find conclusive results lacking alternative explanations by controlling for the effector confound