Effects of transcranial alternating current stimulation on measures of cognition and symptom scores in Chinese patients with schizophrenia.

Transcranial alternating current stimulation (tACS) may have effects on cognition and symptoms in psychiatric illness but there have been few randomized controlled studies in people with schizophrenia. We conducted a randomized sham-controlled double-blind study of 40 Hz tACS on measures of cognition and symptoms scores in 50 patients diagnosed with DSM-5 schizophrenia. tACS was delivered in 10 sessions (20 min each) over a 2-week period. Evaluations were conducted with multiple cognitive and symptom batteries after 10 sessions and at 2 weeks and 4 weeks post-treatment, and also on-line during the tACS stimulation session 1. The primary outcome measured changes in the MATRICS overall composite score. The results showed no statistically significant (P < 0.05) effects of active vs. sham on improvement in any of the cognitive measures or PANSS rated positive or negative symptoms. There was a trend (P < 0.06) for the MATRICS Domain score of verbal learning to show greater improvement of active tACS compared to sham within 1-2 days after the 10 tACS sessions. Additional trials are needed to determine the effective tACS parameters targeting cognition and symptoms of schizophrenia.