Difference of EEG in length of the training period

EEGs were measured to study the differences in the length of the Qigong training period of four trainees and examined those changes just after one year. Their training periods were from 17 months to 3 years for the first test. The method of Qigong, Zhen-qi-yun-xing-fa, performed by sitting quietly, is a kind of the internal quiet Qigong. At the first test, a waves on the occipital region increased during Qigong more than in the resting state. However, one year after, they increased only a little. A ratio of the effective amplitude of the a waves on the frontal to the occipital regions (Fp2/O2) was calculated. The longer the training periods were, the larger the ratio tended to be. The ratios of Qigong masters are usually large and during Qigong they become larger, i.e., the frontal a waves become larger than the occipital ones. On the trainees, clear differences were hardly found between in the resting state and during Qigong in the first year. However, the next year the ratio became a little larger during Qigong. The frequency of the alpha waves became slower while the deep meditation-like state. On the subjects whose alpha waves became much slower, theta waves appeared around the frontal-midline position, Fz.