Copyright
©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
Delayed improvements in visual memory task performance among chronic schizophrenia patients after high-frequency repetitive transcranial magnetic stimulation
Xiang-Dong Du, Zhe Li, Nian Yuan, Ming Yin, Xue-Li Zhao, Xiao-Li Lv, Si-Yun Zou, Jun Zhang, Guang-Ya Zhang, Chuan-Wei Li, Hui Pan, Li Yang, Si-Qi Wu, Yan Yue, Yu-Xuan Wu, Xiang-Yang Zhang
Xiang-Dong Du, Zhe Li, Nian Yuan, Ming Yin, Xue-Li Zhao, Xiao-Li Lv, Si-Yun Zou, Jun Zhang, Guang-Ya Zhang, Chuan-Wei Li, Suzhou Guangji Hospital, Affiliated Guangji Hospital of Soochow University, Suzhou 215008, Jiangsu Province, China
Hui Pan, Li Yang, Department of Psychiatry, Third People’s Hospital of Changshu, Changshu 215501, Jiangsu Province, China
Si-Qi Wu, School of Psychology and Mental Health, North China University of Science and Technology, Langfang 065201, Hebei Province, China
Yan Yue, Yu-Xuan Wu, Department of Psychiatry, Medical College of Soochow University, Suzhou 215000, Jiangsu Province, China
Xiang-Yang Zhang, CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing 100101, China
Author contributions: Du XD contributed to the project administration, funding acquisition, supervision, wrote the review and editing; Li Z contributed to clinical data collection, wrote review and editing; Yuan N contributed to the data curation, investigation; Yin M, Zhao XL, Lv XL, Zou SY, Zhang J, Li CW, Pan H, Yang L, Wu SQ, Yue Y and Wu YX contributed to the conceptualization, data curation and investigation; Zhang XY contributed to the formal analysis, wrote the original draft; Du XD, Li Z and Yuan N have congtributed equally to this work.
Supported by Key Diagnosis and Treatment Program of Suzhou, No. LCZX201919 and No. LCZX202016; The Scientific and Technological Program of Suzhou, No. SS201752 and No. SS202069; and Introduction Project of Suzhou Clinical Expert Team, No. SZYJTD201715.
Institutional review board statement: This study obtained approval from the Institutional Review Board of Suzhou Guangji Psychiatric hospital. All methods were performed in accordance with the Declaration of Helsinki.
Informed consent statement: Each subject provided written informed consent to participate in the study after a researcher staff explained the whole study to each of them.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
Data sharing statement: The data will be available on request from the readers.
STROBE statement: The authors have read the STROBE Statement—checklist of items, and the manuscript was prepared and revised according to the STROBE Statement—checklist of items.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
https://creativecommons.org/Licenses/by-nc/4.0/ Corresponding author: Xiang-Yang Zhang, Doctor, Professor, CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, No. 16 Lincui Road, Chaoyang District, Beijing 100101, China. zhangxy@psych.ac.cn
Received: February 28, 2022
Peer-review started: February 28, 2022
First decision: April 18, 2022
Revised: April 24, 2022
Accepted: July 22, 2022
Article in press: July 22, 2022
Published online: September 19, 2022
BACKGROUND
Cognitive impairments are core characteristics of schizophrenia, but are largely resistant to current treatments. Several recent studies have shown that high-frequency repetitive transcranial magnetic stimulation (rTMS) of the left dor-solateral prefrontal cortex (DLPFC) can reduce negative symptoms and improve certain cognitive deficits in schizophrenia patients. However, results are inconsistent across studies.
AIM
To examine if high-frequency rTMS of the DLPFC can improve visual memory deficits in patients with schizophrenia.
METHODS
Forty-seven chronic schizophrenia patients with severe negative symptoms on stable treatment regimens were randomly assigned to receive active rTMS to the DLPFC (n = 25) or sham stimulation (n = 22) on weekdays for four consecutive weeks. Patients performed the pattern recognition memory (PRM) task from the Cambridge Neuropsychological Test Automated Battery at baseline, at the end of rTMS treatment (week 4), and 4 wk after rTMS treatment (week 8). Clinical symptoms were also measured at these same time points using the Scale for the Assessment of Negative Symptoms (SANS) and the Positive and Negative Syndrome Scale (PANSS).
RESULTS
There were no significant differences in PRM performance metrics, SANS total score, SANS subscores, PANSS total score, and PANSS subscores between active and sham rTMS groups at the end of the 4-wk treatment period, but PRM performance metrics (percent correct and number correct) and changes in these metrics from baseline were significantly greater in the active rTMS group at week 8 compared to the sham group (all P < 0.05). Active rTMS treatment also significantly reduced SANS score at week 8 compared to sham treatment. Moreover, the improvement in visual memory was correlated with the reduction in negative symptoms at week 8. In contrast, there were no between-group differences in PANSS total score and subscale scores at either week 4 or week 8 (all P > 0.05).
CONCLUSION
High-frequency transcranial magnetic stimulation improves visual memory and reduces negative symptoms in schizophrenia, but these effects are delayed, potentially due to the requirement for extensive neuroplastic changes within DLPFC networks.
Core Tip: The main objective of this study was to evaluate the efficacy of high-frequency repetitive transcranial magnetic stimulation (rTMS) in the treatment of visual memory disorders in schizophrenia. Forty-seven patients with chronic schizophrenia who had significant negative symptoms during stabilization therapy were randomly assigned to two groups: Active rTMS over dorsolateral prefrontal cortex (n = 25) or false stimulation (n = 22) for 4 wk, followed by 4 wk of follow-up. Our results suggest that high-frequency transcranial magnetic stimulation improves visual memory function and relieves negative symptoms in patients with schizophrenia, but with a delay.
