EEG coherence increases between and within
the cerebral hemispheres during Transcendental Meditation. EEG coherence
is a quantitative index of the degree of long-range spatial ordering of
the brain waves. The chart on the left shows that for a 2-week meditator,
EEG coherence increased during the period of meditation. The chart on the
right, of a 2-year meditator, shows high levels of coherence even before
meditation began, spreading of coherence to high and lower frequencies
about half way through the meditation period, and continuing high coherence
even into the eyes-opened period after meditation.
Reference I: The Coherence Spectral
Array (COSPAR) and its application to the study of spatial ordering in the EEG, Proceedings of the
San Diego Biomedical Symposium 15: 1976. Reference II: Electrophysiologic characteristics of respiratory
suspension periods occurring during the practice of the Transcendental Meditation program, Psychosomatic
Medicine 46: 267–276, 1984.
