High-Frequency Cerebral Activation and Interhemispheric Synchronization Following Sudarshan Kriya Yoga as Global Brain Rhythms: The State Effects

CONTEXT: Respiration is known to modulate neuronal oscillations in the brain and is measured by electroencephalogram (EEG). Sudarshan Kriya Yoga (SKY) is a popular breathing process and is established for its significant effects on the various aspects of physiology and psychology. AIMS: This study aimed to observe neuronal oscillations in multifrequency bands and interhemispheric synchronization following SKY. SETTINGS AND DESIGN: This study employed before- and after-study design. SUBJECTS AND METHODS: Forty healthy volunteers (average age 25.45 ± 5.75, 23 males and 17 females) participated in the study. Nineteen-channel EEG was recorded and analyzed for 5 min each: before and after SKY. Spectral power for delta, theta, alpha, beta, and gamma frequency band was calculated using Multi-taper Fast Fourier Transform (Chronux toolbox). The Asymmetry Index was calculated by subtracting the natural log of powers of left (L) hemisphere from the right(®) to show interhemispheric synchronization. STATISTICAL ANALYSIS: Paired t-test was used for statistical analysis. RESULTS: Spectral power increased significantly in all frequency bands bilaterally in frontal, central, parietal, temporal, and occipital regions of the brain after long SKY. Electrical activity shifted from lower to higher frequency range with a significant rise in the gamma and beta powers following SKY. Asymmetry Index values tended toward 0 following SKY. CONCLUSIONS: A single session of SKY generates global brain rhythm dominantly with high-frequency cerebral activation and initiates appropriate interhemispheric synchronization in brain rhythms as state effects. This suggests that SKY leads to better attention, memory, and emotional and autonomic control along with enhanced cognitive functions, which finally improves physical and mental well-being.