Neural correlates of spatial attention bias: Changes in functional connectivity in attention networks associated with tDCS. (15th December 2022)

• Record Type: Journal Article
• Authors: Tsujimoto, Kengo; Nishida, Daisuke; Tahara, Masatoshi; Liu, Meigen; Tsuji, Tetsuya; Mizuno, Katsuhiro
• Is Part Of: Neuropsychologia. Number 177(2022)
• Publication Date: 2022-12-15
• Subjects: Neglect-like effect -- Biparietal-tDCS -- Functional connectivity -- Attention network -- Visual search task; Neuropsychology -- Periodicals; Neurology -- Periodicals; Psychophysiology -- Periodicals; Neuropsychologie -- Périodiques; Neuropsychology; Periodicals; Electronic journals; 616.8
• DOI: 10.1016/j.neuropsychologia.2022.108417
• Languages: English
• ISSNs: 0028-3932

Abstract

Abstract: The prevailing theory concerning the pathophysiology of unilateral spatial neglect is that it is caused by an interhemispheric imbalance in attention networks. Previous studies have demonstrated that repetitive transcranial magnetic stimulation or transcranial direct current stimulation (tDCS) delivered over the right posterior parietal cortex can induce transitory neglect-like deficits in healthy individuals. We examined whether right cathodal and left anodal tDCS delivered over the posterior parietal cortex could produce neglect-like deficits and change the resting-state functional connectivity (rsFC) of attention networks. We found that the reaction time for targets in the left hemifield was significantly prolonged during two different types of visual search tasks, and rsFC of the attention networks was altered by tDCS. Furthermore, the change in the reaction times for the left visual target in the two different tasks significantly correlated with the change in the rsFC of either the right dorsal attention network (DAN) or right ventral attention network (VAN) based on the tasks. These results suggest that tDCS delivered to the posterior parietal cortex bilaterally induced neglect-like deficits by altering the connectivity of the attentional networks through excitability changes in the cortical area under the electrode. The results of this study are consistent with the hypothesis that the cause of neglect is the interhemispheric imbalance of attention networks. This is the first study to demonstrate that local cortical stimulation can induce changes not only in the local brain function but also in the cortical networks in healthy individuals. Highlights: Simultaneous right cathodal and left anodal transcranial direct current stimulation on bilateral posterior parietal cortex induces a neglect-like behaviour and changes functional connectives (FCs) in right dorsal attentional network (DAN) and ventral attentional network (VAN). Significant correlations were found between the strength of the effect and FC in either DAN or VAN depending on types of attention task. This study demonstrated that stimulation of local cortical regions induces not only changes in local brain function but also alterations in related cortical network.