Effect of magnetic stimulation at acupoint on event related potential MMN during mental fatigue

In order to explore an objective method to detect the mental fatigue and to investigate whether magnetic stimulation at acupoint can relieve mental fatigue, a model of mental fatigue was built by reading English scientific papers continuously for 4 hours in this study. The mismatch negativity (MMN) component of event-related potentials (ERPs) was extracted using auditory oddball paradigm as the evaluation index of mental fatigue. Fourteen college students performed the experiment. After the subjects reached mental fatigue, their SHENMEN, HEGU and LAOGONG acupoints were stimulated by magnetic stimulator. The waveforms of ERPs before mental fatigue, after mental fatigue and after magnetic stimulation from each subject were analysed. The results show that mean amplitudes of MMN at fronto-central electrodes after mental fatigue are significantly lower than those before mental fatigue, and the mean amplitudes of MMN after magnetic stimulation are higher than those after mental fatigue. It suggests that the ability of brain to filter useful information after mental fatigue is reduced, and after magnetic stimulation, the ability is increased. Magnetic stimulation at acupoint relieves the state of fatigue.