Transcranial Direct Current Stimulation (tDCS) to Improve Gesture Control

The majority of schizophrenia patients is impaired in hand gesture performance, which contributes to poor functional outcome and poor communication skills. The left inferior frontal gyrus (IFG) and the left inferior parietal lobe (IPL) are key nodes of the gesture network, which is less active in patients with schizophrenia. Here, the investigators test single 10 min sessions of tDCS known to either enhance or inhibit local brain activity for app. 1 hour. The investigators aim to determine, which protocol may improve gesture performance in patients and healthy controls. This is a randomized, double-blind, cross-over, placebo-controlled single-center trial in 20 patients with schizophrenia spectrum disorders and 20 healthy controls. Gesture performance will be tested immediately after each tDCS session, which are separated by 24 hours. Results of this study will inform larger interventional trials comparing 2 tDCS protocols with repeated administration.