Abstract: BACKGROUND: In stroke patients, cerebral neurological deficits can further lead to upper limb motor dysfunction, and the recovery of cerebral and upper limb motor functions plays an important role in improving the ability of daily living. Although studies have investigated the immediate effects of a single transcranial direct current stimulation on the electrical activity of the brain in stroke patients, the therapeutic effects of short-term transcranial direct current stimulation need to be further explored.
OBJECTIVE: To evaluate the effects of transcranial direct current stimulation on upper limb motor function and brain function in stroke patients immediately and after 3 weeks of intervention.
METHODS: A total of 30 patients with hemiplegia after ischemic stroke were recruited and randomly divided into an experimental group (n=15) and a control group (n=15). The experimental group received bipolar transcranial direct current stimulation on the basis of conventional rehabilitation, while the control group received pseudo-transcranial direct current stimulation. Treatments in each group lasted for 3 weeks. The Fugl-Meyer rating scale for the upper limb, the Wolf Motor Function Test and resting-state electroencephalography were performed before the intervention, after the first intervention and after 3 weeks of intervention.
RESULTS AND CONCLUSION: (1) There was no significant change in the control group immediately after intervention compared with before intervention, while the Fugl-Meyer rating scale score in the experimental group increased immediately after intervention (P < 0.05). (2) After 3 weeks of intervention, the Fugl-Meyer rating scale score, Wolf Motor Function Test score and electroencephalography frequency band changes were significantly improved in the two groups, and the improvement effect in the experimental group was more obvious (P < 0.05). (3) Correlation analysis showed that the difference between Fugl-Meyer rating scale and Wolf Motor Function Test scores before and after treatment in the experimental group was negatively correlated with the average brain power of δ (r=-0.716 and r=-0.546, respectively), and positively correlated with the average brain power of α (r=0.520 and r=0.669, respectively). To conclude, the addition of bipolar transcranial direct current stimulation to conventional rehabilitation treatment could effectively improve the brain function and upper limb motor function of patients with ischemic stroke. Improvement in upper limb motor function is associated with a tendency toward normalization of brain function recovery.

Key words: transcranial direct current stimulation, stroke, bilateral stimulation, rehabilitation training, upper limb motor function, brain function, brain electrical activity, neurorehabilitation