Abstract:Objective To study the mechanism of repetitive transcranial magnetic stimulation (rTMS) based on task state functional magnetic resonance imaging (fMRI) to promote the recovery of motor function in stroke patients with dyskinesia.Methods A total of 120 stroke patients with motor impairment admitted to our hospital from January 2017 to January 2019 were randomly divided into high-frequency group, low-frequency group, and pseudo-stimulation group, with 40 cases in each group. The high frequency group was treated with high frequency rTMS (10 Hz), the low frequency group was treated with low frequency rTMS (1 Hz), and the false stimulus group was treated with rTMS. The changes of upper limb function, motor function, balance function, cortical excitability, and task-state fMRI images before and after treatment were analyzed.Results There was no significant difference between the three groups in gender, average age, focus location, and other general data (P > 0.05). The changes of FMA, wmft, MAS, BBS, MEP latencies, and maximum amplitude of MEP in upper limb of high frequency group, low frequency group, and false stimulation group before treatment, 5 days after treatment, and 3 months after treatment were compared by ANOVA of repeated measurement data (P < 0.05). The changes of FMA and wmft in upper limb of high frequency group, low frequency group, and false stimulation group were different. The scores of MAS and BBS in high frequency group, low frequency group, and false stimulation group were different (P < 0.025). The changes of MEP latency and MEP maximum amplitude in the affected hemisphere of high frequency group, low frequency group and false stimulation group were different (P < 0.05). Compared with the pre-treatment, there was no improvement in the activation of the patient's side motor area in the false stimulation group after treatment, the activation of the patient's side motor area in the low frequency group increased, the activation of the healthy side motor area decreased, and the activation of the patient's side motor area in the high frequency group increased significantly. After treatment, M1 and SMA in the affected side of the patients in the high frequency group were significantly positively activated compared with the false stimulation group; M1 in the affected side of the patients in the low frequency group was significantly negatively activated compared with the false stimulation group; M1 and SMA in both sides of the patients in the high frequency group were significantly positively activated compared with the low frequency group.Conclusion Based on fMRI, it was found that the mechanism of rTMS promoting motor function recovery in stroke patients with motor dysfunction may be related to the improvement of cortical excitability and local nerve activity.