Effects of repetitive transcranial magnetic stimulation on electroencephalographical measures of post-stroke upper limb dysfunction: study protocol for a randomized controlled trial

Background Patients with stroke would experience upper limb dysfunction, leading to functional impairments in daily living and placing a burden on society and families. Repetitive transcranial magnetism stimulation (rTMS), a non-invasive neuromodulation tool, has been shown to upper limb dysfunction. However, the clinical efficacy and the underlying neurophysiological mechanisms of optimal intensity of rTMS to promote motor recovery of stroke patients with upper limb function need further investigations. This study aims to investigate the changes in the brain neurophysiological mechanisms ranging from cortical oscillatory activity to the effectiveness of the complex network after low frequency (LF)- and high frequency (HF)-rTMS on motor areas of patient post-stroke. Methods A total of 42 stroke patients with upper limb dysfunction will be randomized into high frequency (HF) rTMS group, low frequency (LF) rTMS group (1:1 ratio). The HF-rTMS group will use 90% rest motor threshold (RMT), 10 Hz acting with the ipsilesional M1 for a total of 1500 pulses for 2 weeks, and the LF-rTMS group acting on the contralesional M1 with the same parameters, except that 1 Hz was used. The National Institutes of Health Stroke Scale (NIHSS), The motor deficit (the Fugl–Meyer Assessment upper Extremity (FMA-UE)), Modified Barthel Index (MBI), and resting-state electroencephalogram (EEG) signals will be obtained at the baseline and within one week after the rTMS. Discussion This study will contribute to the understanding of the neurophysiological changes in the brain corresponding to the clinical effects of HF- and LF-rTMS in patients with stroke. Trial registration This study was approved by the Ethics Committee of the Hong Kong Polytechnic University and the Ethics Committee of the Affiliated Hospital of Southwest Medical University (HSEARS20220303002). This study was registered in November 2022 (https://www.chictr.org.cn). Clinical trial registration number is ChiCTR2200065639.