Master of Science
Dr. Matthew Heath
Goal-directed reaches performed with limb vision (i.e., closed-loop: CL) are more accurate than their limb occluded (i.e., open-loop: OL) counterparts. This finding is frequently attributed to the use of online limb vision to effect trajectory amendments. Notably, however, the central planning of CL and OL reaches may also influence trajectory control. To that end, I examined the behavioural and event-related brain potentials (ERP) of reaches in a target perturbation paradigm wherein information regarding the nature of response (CL or OL) was provided prior to response cuing. CL reaches exhibited earlier and more effective trajectory amendments than OL reaches. Moreover, CL and OL reaches differed with regard to ERP components related to the allocation of visuospatial attention (i.e., the N1) and visuomotor integration (i.e., the P2). These results suggest that advanced knowledge related to the availability of online limb vision increases the visuospatial processing of the reaching limb and optimizes trajectory amendments.
Mulla, Ali, "Electroencephalographic correlates of spatial attention index the degree of online control in goal-directed reaching" (2012). University of Western Ontario - Electronic Thesis and Dissertation Repository. Paper 567.