The following is a summary of “Network-level mechanisms underlying effects of transcranial direct current stimulation (tDCS) on visuomotor learning in schizophrenia,” published in the November 2023 issue of Psychiatry by Sehatpour et al.
Motor learning is a pivotal skill crucial for daily functioning, yet individuals with schizophrenia (Sz) often exhibit impaired motor performance linked to compromised social and functional outcomes. Transcranial direct current stimulation (tDCS), a non-invasive brain stimulation method, holds promise in enhancing motor learning in Sz by influencing brain function.
The researchers conducted a study utilizing the Serial Reaction Time Task (SRTT) and simultaneous tDCS and EEG recording to delve into the mechanisms underlying Sz’s motor and procedural learning deficits. Their aim was to refine non-invasive brain stimulation techniques to address neurocognitive dysfunction. Their study involved 27 Sz individuals and 21 healthy controls (HC). Participants performed the SRTT task while receiving both sham and active tDCS, with concurrent EEG recording. The study group evaluated reaction time (RT), neuropsychological metrics, and global functioning. The SRTT performance was notably impaired in Sz individuals, correlating significantly with motor-related, working memory measures and overall function. Analysis of EEG data revealed beta-band coherence across supplementary-motor, primary-motor, and visual cortex, forming a network critical for SRTT performance.
Notably, motor-cathodal and visual-cathodal stimulations induced significant modulation in coherence, specifically across the motor-visual nodes of the network, accompanied by a substantial improvement in motor learning in both controls and patients. Their findings confirm previous reports of SRTT impairment in Sz and underscore the significant reversal of deficits through tDCS. This supports the ongoing development of tDCS as a potential avenue for enhancing plasticity-based interventions in Sz, alongside the utilization of source-space EEG analysis to probe the underlying neural mechanisms.
Source: nature.com/articles/s41398-023-02656-3
