Effect of muse I e fat i gue and motor I earn i hg on p I ast i c changes of motor and sensory cortices in cerebrum

点击翻译按钮获取中文摘要

We examined how muscle fatigue and motor learning as typing influenced plastic changes of motor and sensory cortices in cerebrum. Our results were to be shown below that ; 1) the combination of two short typing practices for ten min. and a gripping fatigue for two min. relatively easily induced the decrease of short-interval intracortical inhibition(SICI) during recovery period although only two typing practices or only a gripping fatigue did not change SICI and the second typing velocity after gripping fatigue enhanced compared with the first one, 2) on next stage, we tried how sensory excitability by a gripping fatigue and/or two typing practices contributed to plastic changes in motor cortex by using EEG or the combination of peripheral electric stimulation(PES) and TMS, and the short typing practice did not change Psoo in sensory evoked potential(SEP) but the gripping fatigue trended to decrease Psoo immediately after it and recovered until 10 min, and 3) the combination of two typing practices and a gripping fatigue did not change short afferent inhibition(SAI) and long afferent inhibition(LAI) by PES and TMS. Muscle fatigue gave the different effects between SEP in EEG and SAI and LAI in sensory cortex. Our finding was that the disinhibition of SICI like plastic change in motor cortex directly depended on muscle fatigue and fingers control practice but this disinhibition would be not influenced by changes of peripheral sensory excitability due to fatigue and control tasks. It is seemed that the combination of muscle fatigue and motor learning would be effective at getting plastic change in motor cortex.