Poster D53, Monday, March 27, 8:00 – 10:00 am, Pacific Concourse
rTMS stimulation on right frontal and parietal reduces the impairment of object location changes on object identity change detection
PING YANG1,2,3,4, LING LI1,2,3,4; 1Key Laboratory for NeuroInformation of Ministry of Education, 2High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, 3Center for Information in Medicine, 4University of Electronic Science and Technology of China
In visual working memory (VWM) task, object location plays a crucial role in object identity change detection, since it indicates the spatial coordinates of the object and the focus of attention allocation. In our previous fMRI study, subjects responded faster in the object color change detection when the probe array share the same spatial location as the memory array compared to when it was changed. Subjects responded more accurately in location match compared to location no-match conditions, when a higher VWM load was utilized. Our fMRI results indicate right supramarginal gyrus (SMG) (MNI = 57, -48, 33) and right inferior frontal gyrus (IFG) (MNI = 54, 15, 6) were responsible for the object location discrimination. To confirm the specialized role of these two regions, we applied a 10 Hz with 5 pulses repetitive transcranial magnetic stimulation (rTMS) over right SMG and right IFG, as well as an additional control site (CZ) when the probe array onset. In the CZ stimulation, subjects responded more accurately during the match versus on-match object location condition only for higher VWM load of 4, consistent with previous fMRI study. However, in the SMG and IFG stimulation, the location match advantage effect disappeared. For the reaction time (RT), all of three regions stimulation showed the location match advantage, which is shorter RT for the location match compared to no-match condition. Overall, our results support the specialized role of right SMG and right IFG in the object location discrimination implicated in the object color change detection.
Topic Area: EXECUTIVE PROCESSES: Working memory