Differences between the EEG of Zen priests and internal qigong masters

Electroencephalograms (EEGs) of Japanese Zen priests and Chinese qigong masters were measured and the differences studied. During almost all types of qigong training, the frequency of the alpha waves became faster (+0.5 ±1.0 Hz). During deep Zen meditation, however, it became very slower (—1.0±1.5 Hz), and sometimes theta waves were also found.

As we have previously reported, the alpha waves of qigong masters spread to their frontal area while they are practicing qigong. These frontal alpha waves synchronized remarkably well with the occipital alpha waves. This means the phase difference between the occipital and the frontal alpha waves became shorter. We used an indicator tau m to represent this phase difference. During deep Zen meditation, this tau m became longer, although many alpha waves appeared on the frontal area. It has been found in other experiments that concentrating on some tasks, such as calculations, made the tau m shorter. Internal qigong may be considered to be a meditation in which the meditator concentrates to internal 'qi' or some consciousness. On the other hand, Zen meditation may release the meditator's self from all external concerns.