Neural activity is modulated by spontaneous and volitionally controlled breathing

Recent studies have provided evidence regarding respiration-brain coupling, but how continuously varying dynamics of breathing modulate neural activity is not known. We examined whether the neural state differs between spontaneous and volitionally controlled breathing and across the phases of breathing, inspiration and expiration. Magnetoencephalography with a respiratory belt was used to record cortical oscillatory activity during spontaneous, deep, and square breathing (n=33). Alpha power was suppressed during inspiration and increased during expiration (p<0.01) indicating dynamically fluctuating neural states across the respiratory cycle. Compared to spontaneous and square breathing, alpha power increased during deep breathing (p<0.01). We also observed a steeper aperiodic slope and a broadband shift in the power spectrum during square breathing in comparison with spontaneous breathing suggesting that spectral characteristics of neural activity are modulated by the rate, depth, and pattern of breathing. Altogether, we demonstrate that neural activity is modulated by breathing techniques and phases of breathing.