Objectives:
This study aims to investigate the therapeutic effect of repetitive transcranial magnetic stimulation (rTMS) on the negative symptoms of chronic schizophrenia and serum brainderived neurotrophic factor (BDNF).

Methods:
A total of 86 patients with chronic schizophrenia hospitalised from March to October 2019 were randomly assigned to the active rTMS group or the sham rTMS group, with 43 patients in each group. All patients were administered paliperidone orally at a dose of 3–6 mg/d, and rTMS treatment was given to the active rTMS group. The Positive and Negative Syndrome Scale (PANSS) score and the serum BDNF concentration were calculated in both groups at baseline and after two and four weeks of treatment

Results:
There were no statistically significant differences in the PANSS scores and serum BDNF concentrations between the two groups before treatment (p > 0.05). However, after four weeks of treatment, the change in the score on the negative symptom scale in the active rTMS group was greater than in the sham rTMS group (p < 0.05), and the serum BDNF levels in the active rTMS group were higher than in the sham rTMS group (p < 0.05).

Conclusions:
Four weeks of continuous rTMS treatment can effectively improve the negative symptoms of schizophrenia, and the serum concentration of BDNF increases as the duration of rTMS treatment increases.