The present study was undertaken to analyze the effects of qigong on 12-channel EEG compressed spectral array, EEG brain topographic mappings, the statistical T-test topographic mappings, and the correlation coefficient topomappings for different practicers of qigong.
Total number of the subjects were 30, among whom 10 were long-term practicers of qigong (called qigong masters), 10 were short-term practicers (called qigong beginners), the other 10 were in the control group without any qigong exercise. All the members were in good health, and had no history of neurological disease or head injury.
The method of the study was as follows:
The subjects sat comfortably in chairs in a quiet chamber while EEG recordings were made from silver disc electrodes at the following locations Fp 1, Fp 2, C 3, C 4, F 7, F 8, T 5, T 6, Fz, Pz, and 01, 02. EEGs were recorded on paper, and were simultaneously recorded onto a 21-channel analog magnetic tape recorder (SONY A-821). EEG signals were recorded for 5 min. prior to, 10 min. during, and 5 min. after the qigong exercise.
The EEG was continually monitored in order to minimize the effects of muscle activity, drowsiness, eye blinks on off-line computer processing (SIGNAL PROCESSOR 7T17s) . The computer program involved: ( I ) initial sampling processing; (2) window and periodogram arithmetic processing; (3) compressed spectral array processing; (4) linear three-dimensional interpolation processing; ( 5 ) topographic mapping processing; ( 6 ) statistical T-test topographical mapping analysis, and (7)correlation coefficient topographical mapping processing.
The spectral analysis was performed on the background of EEG using to FFT for the delta band, the theta band, the alpha 1 band, the alpha 2 band, the beta I band, and the beta 2 band.
The results showed that the EEGs for qigong masters (with over 10 years of experience) during the qigong exercise were different from that of the others. In the compressed spectral array, the alpha rhythm originally predominant in the parieto occipital regions decreased, and the relatively unmarked alpha rhythm in the frontal region increased. The T-test topographical maps showed that in alpha 1 topographical map only the T values of the anterior half of the brain were over T (9) =2.4536, therefore, the increase in alpha 1 component in the frontal regions was significant. Moreover, we found that the alpha 1 component gradually increased and alpha 2 component gradually decreased during the qigong state. This indicated the slowing of alpha peak frequency during the qigong state. In comparison with that of the qigong masters, the T-test topographic mapping for the qigong beginners showed that the increase in alpha I component in the frontal regions was not significant during the qigong exercise. There was no change of the alpha rhythm in the control group (without any qigong exercise) who were in the resting state with eyes closed.
Quantitative analysis of EEGs in subjects in the process of qigong exercise and in the resting state showed that changes in EEGs during the process of qigong exercise were specific, and different from patterns associated with awakening and drowsiness, or any state between these two extremes. The EEGs of 10 qigong masters in the process of qigong exercise were clearly different from those recorded during a resting state with eyes closed. The peak amplitudes of alpha rhythm increased during the qigong state in all 10 qigong masters and this change was statistically significant, especially in the frontal regions. This result was the same as the result of T-test topographical mapping, which showed that the increase in alpha I component in the frontal regions was statistically significant (P<O.05). The change in alpha rhythm in the posterior regions was not significant. Thus, the qigong state appears to be a special and unusual state of excitation.
