title: 1-Hz Repetitive Transcranial Magnetic Stimulation over the Posterior Parietal Cortex Modulates Spatial Attention.
abstract: Lesion and neuroimaging studies have suggested that regions in the posterior parietal cortex (PPC) are involved in visual spatial attention. The aim of this study was to investigate the potential effects on spatial attention resulting from a transient parietal impairment induced by 1-Hz repetitive transcranial magnetic stimulation (rTMS). We examined 50 healthy subjects using the attention network test (ANT) after first applying rTMS to right or left PPC. The right parietal rTMS, but not left PPC rTMS, caused a significant slowing in the mean reaction time (RT) to target presentation following a spatial cue during the ANT test. There were no significant effects of rTMS on mean RT under the no-cue, center-cue, and double-cue conditions, or for each flanker type among the experimental groups. Moreover, after rTMS to the right PPC, test subjects displayed deficits in networks related to alerting and orienting, whereas they exhibited improvement following rTMS to the left PPC. These findings indicate that the right PPC serves an important function in spatial orienting and the alerting activities. We interpreted the enhancement in alerting and spatial orienting function following low-frequency rTMS of left PPC as reflecting a disinhibition of right PPC via an inter-hemispheric inhibition account.
authors: Department of Rehabilitation Medicine, The First Affiliated Hospital of Sun Yat-sen University , Guangzhou , China.
authors: Guang-Qing
authors: GQ
authors: Xu
authors: Department of Rehabilitation Medicine, Guangzhou First People's Hospital of Guangzhou Medical University , Guangzhou , China.
authors: Yue
authors: Y
authors: Lan
authors: Department of Rehabilitation Medicine, The First Affiliated Hospital of Sun Yat-sen University , Guangzhou , China.
authors: Qun
authors: Q
authors: Zhang
authors: Department of Rehabilitation Medicine, The First Affiliated Hospital of Sun Yat-sen University , Guangzhou , China.
authors: Dong-Xu
authors: DX
authors: Liu
authors: Department of Rehabilitation Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China; Department of Neurology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
authors: Xiao-Fei
authors: XF
authors: He
authors: Department of Rehabilitation Medicine, Guangzhou First People's Hospital of Guangzhou Medical University , Guangzhou , China.
authors: Tuo
authors: T
authors: Lin
keywords: inter-hemispheric competition; lesion; magnetic stimulation; posterior parietal cortex; spatial attention