Huang Huang1, Wei Cai Liu2, Yu Han Song3. 1. Department of Stomatology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, PR China. 2. Laboratory of Oral Biomedical Science and Translational Medicine, School of Stomatology, Tongji University, Middle Yanchang Road 399, Shanghai 200072, PR China. Electronic address: weicai_liu@tongji.edu.cn. 3. Laboratory of Oral Biomedical Science and Translational Medicine, School of Stomatology, Tongji University, Middle Yanchang Road 399, Shanghai 200072, PR China.
Abstract
OBJECTIVE: Repetitive transcranial magnetic stimulation (rTMS) has been widely used to modulate the excitability of the cortical control of limbs muscles, but rarely in the cortical control of human masseter muscles. This study aims to investigate the effects of rTMS on masseter motor-neuron pool excitability in humans. MATERIALS AND METHODS: A total of 20 healthy participants were selected and received a total of three rTMS sessions involving stimulation of the right masseter-motor complex: one session of 10-Hz rTMS, one session of 1-Hz rTMS and one session of sham rTMS at an intensity of 80% of the active motor threshold (AMT). The masseter AMT, motor-evoked potentials (MEPs), cortical-silent period (CSP), and short-interval intracortical inhibition (SICI) were measured before and after each rTMS session. RESULTS: The masseter SICI was significantly decreased following 10-Hz rTMS, with no significant changes in AMT, MEPs or CSP. No significant differences in masseter AMT, MEPs, CSP or SICI were observed in either the 1-Hz, or sham rTMS groups. CONCLUSIONS: The present findings demonstrate that high-frequency rTMS increases masseter motor-neuron pool excitability. Copyright Â
OBJECTIVE: Repetitive transcranial magnetic stimulation (rTMS) has been widely used to modulate the excitability of the cortical control of limbs muscles, but rarely in the cortical control of human masseter muscles. This study aims to investigate the effects of rTMS on masseter motor-neuron pool excitability in humans. MATERIALS AND METHODS: A total of 20 healthy participants were selected and received a total of three rTMS sessions involving stimulation of the right masseter-motor complex: one session of 10-Hz rTMS, one session of 1-Hz rTMS and one session of sham rTMS at an intensity of 80% of the active motor threshold (AMT). The masseter AMT, motor-evoked potentials (MEPs), cortical-silent period (CSP), and short-interval intracortical inhibition (SICI) were measured before and after each rTMS session. RESULTS: The masseter SICI was significantly decreased following 10-Hz rTMS, with no significant changes in AMT, MEPs or CSP. No significant differences in masseter AMT, MEPs, CSP or SICI were observed in either the 1-Hz, or sham rTMS groups. CONCLUSIONS: The present findings demonstrate that high-frequency rTMS increases masseter motor-neuron pool excitability. Copyright Â
Authors: Cecília N Prudente; Mo Chen; Kaila L Stipancic; Katherine L Marks; Sharyl Samargia-Grivette; George S Goding; Jordan R Green; Teresa J Kimberley Journal: Exp Brain Res Date: 2021-12-02 Impact factor: 1.972