From Lung to Brain - Respiration Modulates Neural and Mental Activity

Respiration sustains metabolic activity in all organs, including the brain. Respiration protocols have been developed to manipulate mental states, including their use for therapeutic purposes, e.g., in anxiety disorders. In this systematic review, we discuss evidence that respiration may play a fundamental role in the coordination of neural activity, behavior, and emotion. The main findings are: (i) respiration affects the neural activity of a widespread variety of regions in the a brain; (in) respiration modulates different frequency ranges in the brain's dynamics; (iii) different respiration protocols (spontaneous, hyperventilation, slow or resonance respiration) yield different neural and mental effects; (iv) the effects of respiration on the brain are related to concurrent modulation of biochemical (oxygen delivery, pH) and physiological (cerebral blood flow, heart rate variability) variables. We conclude that respiration may be an integral rhythm of the brain's neural activity. This provides intimate connection of respiration with neuro-mental features like emotion. A respiratory-neuro-mental connection, in turn, holds the promise for a brain-based therapeutic usage of respiration in mental disorders.