![\"\"](\"http:\/\/www.yorku.ca\/yfile\/photos\/20101007\/\/neuroscience_YFile_crop.jpg\") <\/td>\n<\/tr>\n |
| Above: Professor Doug Crawford performs computer-controlled tests to measure the accuracy of Pat Byrne's\u00a0gaze and reach. Byrne, a postdoctoral\u00a0Fellow\u00a0working in York's Centre for\u00a0Vision Research, is hooked up to\u00a0eye-tracking headgear.<\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n \u201cFootball is a good example to illustrate our results. A quarterback trying to deke out the opposition would actually use separate parts of the posterior parietal cortex in rapid succession...to achieve this,\u201d says principal investigator Doug Crawford, professor of psychology in York\u2019s Faculty of Health and Canada Research Chair in Visuomotor Neuroscience.<\/p>\n The findings suggest that within the PPC, the superior parietal occipital cortex (SPOC) specializes in encoding reach goals. \u201cIn the case of trying to fake a pass, SPOC would help you pick the real player you want to throw the ball to,\u201d says Crawford. \u201cThe midposterior intraparietal sulcus (mIPS), would help you to look at the decoy player. Then the angular gyrus (AG) would compare your current hand position to the goal you\u2019re aiming for in order to guide your throw,\u201d he says.<\/p>\n Simply put, SPOC picks the goal, while mIPS and AG are involved more closely in planning the motor functions for both our view and our reach.<\/p>\n Scientists at York\u2019s Centre for Vision Research (CVR) used a non-invasive procedure called transcranial magnetic stimulation (TMS) to create activity in these three areas of the brain. TMS delivers mild, split-second electromagnetic pulses, with little to no side effects for participants.<\/p>\n Participants then performed computer-controlled tests to measure the accuracy of their view and reach, while hooked up to eye-tracking headgear. Both left and right hands were tested, as well as reaching with and without visual feedback. By observing differences between subjects tested both with and without TMS over different brain areas, Crawford and his colleagues were able to map the unique responsibilities of each area.<\/p>\n \u201cBecause mIPS and AG are involved in calculating both hand and eye movement, and SPOC is dedicated to encoding the reach goal, the whole assembly is likely important for hand-eye coordination,\u201d says Crawford.<\/p>\n \u201cIt\u2019s also a good reason to wear a helmet. You wouldn\u2019t want a hard knock on the parietal cortex,\u201d he says.<\/p>\n The study\u2019s lead investigator was kinesiology PhD student Michael Vesia, currently a postdoctoral fellow with the Sunnybrook Research Institute Brain Sciences Research Program at the University of Waterloo. It was co-authored by CVR colleagues Steven Prime, a psychology PhD student, Xiaogang Yan, research associate, and Lauren Sergio, a kinesiology professor in the\u00a0School of Kinesiology & Health Science in York's Faculty of Health.<\/p>\n |