BACKGROUND: The detection of motor evoked potential is utilized to explore neuromuscular finger coordination. The influence of transcranial magnetic stimulation on finger force has been investigated mainly on a singl...BACKGROUND: The detection of motor evoked potential is utilized to explore neuromuscular finger coordination. The influence of transcranial magnetic stimulation on finger force has been investigated mainly on a single finger, and only time-dependent increased target finger force has been detected in the finger force task. OBJECTIVE: To explore the neural mechanism of finger force coordination in the motor cortex by observing the influence of various finger coordination patterns and patterns of transcranial magnetic stimulation (TMS)-induced finger force changes. DESIGN, TIME AND SETTING: Neurophysiological and behavioral study was performed at the Biomedical Engineering Laboratory of Chongqing University from April to June 2008. PARTICIPANTS: A total of 10 healthy, university students, comprising 5 males and 5 females, aged 21-23 years, voluntarily participated in this study. All participants were right-handed, with normal or corrected vision. Individuals with upper limb complaints or other musculoskeletal disorders were excluded. METHODS: A target force-tracking task was conducted on the index finger, the index and middle fingers, and four fingers (index, middle, ring, and little), respectively. Target force trace in a single trial consisted of a 6-second ramp phase, a 20-second constant phase, and a 6-second drop phase. During experimentation, an unpredictable single-pulse TMS (120% motor threshold) was applied to the primary motor cortex (M1) in each phase. MAIN OUTCOME MEASURES: Changes in peak force induced by TMS were obtained for each finger pattern during each force-tracking phase. Differences in force changes were tested between different finger pattems with regard to ramp, constant, and drop phases of target force. RESULTS: Under ramp, constant, and drop phases of target force, the increase in magnetic stimulation-induced finger forces changes positively correlated with the number of fingers involved in the force tracking task. The magnetic stimulation-induced force changes展开更多
基金the National Natural Science Foundation of China, No. 3077054630970758+1 种基金Chongqing Natural Science Foundation, No. 2006BB2043 2007BB5148
文摘BACKGROUND: The detection of motor evoked potential is utilized to explore neuromuscular finger coordination. The influence of transcranial magnetic stimulation on finger force has been investigated mainly on a single finger, and only time-dependent increased target finger force has been detected in the finger force task. OBJECTIVE: To explore the neural mechanism of finger force coordination in the motor cortex by observing the influence of various finger coordination patterns and patterns of transcranial magnetic stimulation (TMS)-induced finger force changes. DESIGN, TIME AND SETTING: Neurophysiological and behavioral study was performed at the Biomedical Engineering Laboratory of Chongqing University from April to June 2008. PARTICIPANTS: A total of 10 healthy, university students, comprising 5 males and 5 females, aged 21-23 years, voluntarily participated in this study. All participants were right-handed, with normal or corrected vision. Individuals with upper limb complaints or other musculoskeletal disorders were excluded. METHODS: A target force-tracking task was conducted on the index finger, the index and middle fingers, and four fingers (index, middle, ring, and little), respectively. Target force trace in a single trial consisted of a 6-second ramp phase, a 20-second constant phase, and a 6-second drop phase. During experimentation, an unpredictable single-pulse TMS (120% motor threshold) was applied to the primary motor cortex (M1) in each phase. MAIN OUTCOME MEASURES: Changes in peak force induced by TMS were obtained for each finger pattern during each force-tracking phase. Differences in force changes were tested between different finger pattems with regard to ramp, constant, and drop phases of target force. RESULTS: Under ramp, constant, and drop phases of target force, the increase in magnetic stimulation-induced finger forces changes positively correlated with the number of fingers involved in the force tracking task. The magnetic stimulation-induced force changes