Systematic Review ARTICLE
Effects of High-Frequency Transcranial Magnetic Stimulation for Cognitive Deficit in Schizophrenia: A Meta-Analysis
- 1Second Clinical Medical College of North Sichuan Medical College, Nanchong Central Hospital, China
- 2Department of Psychiatry, Harvard Medical School, United States
- 3Peking University Third Hospital, China
Objective: Repetitive transcranial magnetic stimulation (rTMS) has been applied to dorsolateral prefrontal cortex (DLPFC) to improve cognitive function of patients with schizophrenia (SZs). The aim of this meta-analysis was to evaluate whether a high-frequency rTMS course could enhance cognitive function in SZs.
Methods: Studies published in PubMed, Cochrane Library, Embase, ScienceDirect, and Web of science were searched until April 2018. The search terms include: ‘repetitive transcranial magnetic stimulation’ or ‘rTMS’, ‘SZ’ or ‘schizophrenia’, and ‘neurocognition’ or ‘neurocognitive performance’ or ‘cognitive effects’ or ‘cognitive’. After screening the literatures according to inclusion and exclusion criteria, extracting data, and evaluating the methodological quality of the included studies, a meta-analysis was performed using RevMan 5.3 software (The Cochrane Collaboration, USA).
Results: A total of 9 studies on cognitive dysfunction of SZs were included and involved 351 patients. A significant efficacy of high-frequency rTMS on working memory in SZs was found compared to sham stimulation (p=0.009, SMD = 0.34). Specifically, rTMS treatment positioned on the left DLPFC, with a total pluses less than 30000 is more significantly more effective in improving the working memory (SMD = 0.33, p = 0.03). No improvement was found in other cognitive processes such as executive function, attention, processing speed, and language function. For the follow-up observations, high-frequency rTMS has long-lasting sustained effects on working memory (SMD = 0.45, p = 0.01) and language function (SMD = 0.77, p = 0.02) in SZs.
Conclusions: High rTMS over the left DLPFC with a total pulses less than 30,000 stimulation could significantly improve working memory in SZs for an extended period of time.
Keywords: Transcranial magnetic stimulation (rTMS), High-freqency, Schizophrenia, Cognition, working memeory
Received: 02 Aug 2018;
Accepted: 25 Feb 2019.
Edited by:Su Lui, Sichuan University, China
Reviewed by:Ryuichiro Hashimoto, School of Medicine, Showa University, Japan
Shinsuke Koike, The University of Tokyo, Japan
Wei Liao, University of Electronic Science and Technology of China, China
Copyright: © 2019 Jiang, Guo, Xing, He, Peng, Du, McClure and Mu. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Qiwen Mu, Second Clinical Medical College of North Sichuan Medical College, Nanchong Central Hospital, Nanchong, Sichuan Province, China, firstname.lastname@example.org