title: Parallel Specification of Visuomotor Feedback Gains during Bimanual Reaching to Independent Goals.
abstract: During goal-directed reaching, rapid visuomotor feedback processes enable the human motor system to quickly correct for errors in the trajectory of the hand that arise from motor noise and, in some cases, external perturbations. To date, these visuomotor responses, the gain of which is sensitive to features of the task and environment, have primarily been examined in the context of unimanual reaching movements toward a single target. However, many natural tasks involve moving both hands together, often to separate targets, such that errors can occur in parallel and at different spatial locations. Here, we examined the resource capacity of automatic visuomotor corrective mechanisms by comparing feedback gains during bimanual reaches, toward two targets, to feedback gains during unimanual reaches toward single targets. To investigate the sensitivity of the feedback gains and their relation to visual-spatial processing, we manipulated the widths of the targets and participants' gaze location. We found that the gain of corrective responses to cursor displacements, while strongly modulated by target width and gaze position, were only slightly reduced during bimanual control. Our results show that automatic visuomotor corrective mechanisms can efficiently operate in parallel across multiple spatial locations.
authors.affiliation: Centre for Neuroscience Studies, Queen's University , Kingston, Ontario, Canada.
authors.forename: Anouk J
authors.identifier: 0000-0003-1740-811X
authors.initials: AJ
authors.lastname: de Brouwer
authors.affiliation: Department of Psychology, Queen's University , Kingston, Ontario, Canada.
authors.forename: Tayler
authors.identifier: 0000-0002-7613-6348
authors.initials: T
authors.lastname: Jarvis
authors.affiliation: Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada; Department of Psychology, Queen's University, Kingston, Ontario, Canada; Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada.
authors.forename: Jason P
authors.initials: JP
authors.lastname: Gallivan
authors.affiliation: Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada; Department of Psychology, Queen's University, Kingston, Ontario, Canada.
authors.forename: J Randall
authors.identifier: 0000-0003-2760-6005
authors.initials: JR
authors.lastname: Flanagan
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D053483:Eye Movement Measurements; D005133:Eye Movements; D056228:Feedback, Sensory; D005260:Female; D006040:Goals; D006225:Hand / Q000502:physiology; D006801:Humans; D008297:Male; D009043:Motor Activity; D011601:Psychophysics; D055815:Young Adult
keywords: motor control; online corrections; vision; visual perturbations