EEG paroxysmal gamma waves during Bhramari Pranayama: A yoga breathing technique.

Here we report that a specific form of yoga can generate controlled high-frequency gamma waves. For the first time, paroxysmal gamma waves (PGW) were observed in eight subjects practicing a yoga technique of breathing control called Bhramari Pranayama (BhPr). To obtain new insights into the nature of the EEG during BhPr, we analyzed EEG signals using time-frequency representations (TFR), independent component analysis (ICA), and EEG tomography (LORETA). We found that the PGW consists of high-frequency biphasic ripples. This unusual activity is discussed in relation to previous reports on yoga and meditation. It is concluded this EEG activity is most probably non-epileptic, and that applying the same methodology to other meditation recordings might yield an improved understanding of the neurocorrelates of meditation.

Conscious Cogn. 2008 Feb 23 Vialatte FB, Bakardjian H, Prasad R, Cichocki A. RIKEN Brain Science Institute, Laboratory for Advanced Brain Signal Processing, 2-1 Hirosawa, Wako-Shi, Saitama-Ken 351-0198, Japan.