Combine Mirror Therapy and tDCS on CPSP

Central poststroke pain (CPSP) refers to the symptom of pain arising after a stroke. Patients with CPSP often complain of various painful or unpleasant sensation. Feelings of pain may interfere with sleep and hugely affect the patients\' quality of life. Non-invasive brain stimulation, such as transcranial direct current stimulation (tDCS), is an emerging nonpharmacological treatment and has been shown to have promising pain reduction effects for patients with CPSP. Mirror therapy (MT), on the other hand, is a contemporary approach that has often been used to facilitate upper extremity motor recovery in patients with stroke. MT has been shown to be effective in ameliorating sensory deficits and reducing shoulder pain. To date, no study has determined whether combining MT with tDCS could reduce pain in patients with CPSP. The goal of this study is to determine the effect of combining MT and tDCS on pain, sensation, motor function, and quality of life in people with CPSP. Forty-five patients with CPSP will be randomly allocated to one of the 3 groups: combining MT with tDCS (MT+tDCS) group, MT with sham tDCS (MT+s-tDCS) group, and sham MT with tDCS (s-MT+tDCS) group. The participants in all groups will receive intervention 30 minutes/day, 3 days/ week, for 3 weeks. The participants in the MT+tDCS group will receive tDCS applied simultaneously with MT for 20 minutes. For the following 10 minutes, the tDCS will be turned off while the electrodes will be kept on the scalp, and the participants will continue with MT. For the MT+s-tDCS group, same tDCS procedures will be applied to the participants except that the stimulator will be turned off within 30 seconds. As for the s-MT+tDCS group, the participants will receive the same tDCS procedure as the MT+tDCS group while a sham MT condition will be applied. Clinical and neurophysiological assessments will be conducted before the treatment (pretest), after 3 weeks of treatment (post-test), and 1 month after the treatment (follow-up test). The assessments will be performed by research assistants who will be blinded to the group allocation of the participants. Mix-model Group × Time repeated measures ANOVAs will be used to determine the intervention effects of the 3 groups.