Brain Responses Evoked by Different-Frequency Magnetic Stimulation at an Acupuncture Point

Time-varying magnetic stimulation can induce electric fields in the neuronal tissues and has been increasingly used in medical researches and clinical applications, such as peripheral nerve stimulation and transcranial magnetic stimulation. An acupuncture point (called acupoint) is a specific point in the human body with high sensitivity to various stimuli. In this paper, different-frequency magnetic stimulation was used to stimulate the Neiguan (PC6) acupoint. The 64 channel electroencephalogram (EEG) signals were recorded before, during, and after stimulation to determine whether magnetic stimulation at PC6 point would modulate cortex excitability and whether the frequency parameter would impact stimulation effects. The results showed that when the stimulation frequency was 0.5 Hz, the amplitudes of brain evoked potentials were much bigger and more cortex areas were activated. It suggested that 0.5 Hz magnetic stimulation at the PC6 acupoint could possess more complicated effects.