Engagement of a parieto-cerebellar network in prism adaptation. A double-blind high-definition transcranial direct current stimulation study on healthy individuals

Prism Adaptation (PA) is a non-invasive method to investigate visuomotor control. Recent neurostimulation studies have proposed an interpretation of the mechanisms underlying PA based on functioning of brain networks, instead of focusing on single brain areas. To test the functioning of the network during a classical PA procedure, here we used for the first time High-Definition transcranial Direct Current Stimulation (HD-tDCS) to simultaneously inhibit or facilitate brain activity in two main nodes of the network, namely the parietal cortex and the cerebellum, in healthy individuals. The main results showed that simultaneous anodal HD-tDCS over the two regions reduced terminal errors during exposure to prism glasses as compared to cathodal and sham stimulation. Conversely, cathodal HD-tDCS reduced after-effect as compared to anodal and sham stimulation following prism removal. Overall, these results provide new insights on the network related to the deployment of PA mechanisms and demonstrate the feasibility of using non-invasive HD-tDCS to modulate the adaptive mechanisms of PA. (c) 2021 Elsevier Ltd. All rights reserved.

Automated summary

The study used High-Definition transcranial Direct Current Stimulation (HD-tDCS) for the first time to simultaneously inhibit or facilitate brain activity in two main nodes of the network, resulting in reduced terminal errors with anodal HD-tDCS and decreased after-effect with cathodal HD-tDCS. This demonstrates the feasibility of using non-invasive HD-tDCS to modulate the adaptive mechanisms of Prism Adaptation.