TY - JOUR
T1 - Parietal rTMS disrupts the initiation but not execution of on-line adjustments to a perturbation of object Size
AU - Glover, S
AU - Miall, Rowland
AU - Rushworth, MFS
PY - 2004/1/1
Y1 - 2004/1/1
N2 - Previous studies have implicated the human parietal lobes in the on-line guidance of action. However, no study to date has examined at what stage in the on-line adjustment process do the parietal lobes play their most critical role. Repetitive transcranial magnetic stimulation (rTMS) was applied over the left intraparietal sulcus as participants reached to grasp a small or large illuminated cylinder. On some trials, the illumination could suddenly switch from the small to large cylinder, or vice-versa. Small-Large switches were associated with relatively early grip aperture adjustments, whereas Large-Small switches were associated with relatively late grip aperture adjustments. When rTMS was applied early in the movement, it disrupted on-line adjustments to Small-Large target switches, but not to Large-Small switches. Conversely, when rTMS was applied late in the movement, it disrupted adjustments to Large-Small target switches but not to Small-Large switches. The timing of the disruption by rTMS appeared linked to the initiation of the adjustment. It was concluded that the left parietal lobe plays a critical role in initiating an on-line adjustment to a change in target size, but not in executing that adjustment. The implications of these results for current views of on-line control are discussed.
AB - Previous studies have implicated the human parietal lobes in the on-line guidance of action. However, no study to date has examined at what stage in the on-line adjustment process do the parietal lobes play their most critical role. Repetitive transcranial magnetic stimulation (rTMS) was applied over the left intraparietal sulcus as participants reached to grasp a small or large illuminated cylinder. On some trials, the illumination could suddenly switch from the small to large cylinder, or vice-versa. Small-Large switches were associated with relatively early grip aperture adjustments, whereas Large-Small switches were associated with relatively late grip aperture adjustments. When rTMS was applied early in the movement, it disrupted on-line adjustments to Small-Large target switches, but not to Large-Small switches. Conversely, when rTMS was applied late in the movement, it disrupted adjustments to Large-Small target switches but not to Small-Large switches. The timing of the disruption by rTMS appeared linked to the initiation of the adjustment. It was concluded that the left parietal lobe plays a critical role in initiating an on-line adjustment to a change in target size, but not in executing that adjustment. The implications of these results for current views of on-line control are discussed.
UR - http://www.scopus.com/inward/record.url?scp=12544253728&partnerID=8YFLogxK
U2 - 10.1162/0898929052880066
DO - 10.1162/0898929052880066
M3 - Article
C2 - 15701244
VL - 17
SP - 124
EP - 136
JO - Journal of Cognitive Neuroscience
JF - Journal of Cognitive Neuroscience
ER -