Comparison of effects of 5 and 20 Hz magnetic field on brain responses.

Effects of 5 and 20 Hz magnetic field (MF) on brain response were compared in 22 normal subjects during selective response (SRP) and selective mental arithmetic (SMA). It was found that significant changes in event-related potentials and EEG power spectra were induced by 5 Hz MF, but changes induced by 20 Hz MF were only in EEG coherence during SMA. The features of brain response changes suggest that the brain is in a more well being state after 5 Hz MF stimulation.