Quantitative EEG Study on Zen Meditation (Zazen)

Abstract

Abstract: Quantitative EEG was continuously recorded prior to and during Zen meditation (Zazen) in 20 monks of the Soto sect (Group P: 10 priests; Group D: 10 disciples) and 10 control subjects with no experience in Zen training (Group C). As shown by an EEG topography during meditation, slow alpha appeared in the majority of subjects regardless of their experience in Zen training, while theta appeared only in Groups P and D predominantly in the frontal region, with its frequency increasing in proportion to an increasing length of experience in Zen training. In the quantitative analysis, in the monks with experience in Zen training, it was suggested that theta 2–3 (6.0–8.0 Hz) waves increased while the degree of increase in alpha 2 (9.0–10.0 Hz) wave was attenuated during the temporal course of meditation. The present EEG changes occurring during meditation may reflect intrinsic changes induced by Zazen, namely a mental state in which despite the attainment of relaxation the quality of consciousness is heightened.