The Naked Truth About Breath and Brain
How you breathe can affect your emotional state.
Posted Dec 08, 2016
Breathe in, breathe out. Seems simple, right? We breath all the time--it's a critical function for being alive! Yet we rarely pay any attention to our breathing unless we get very excited or agitated and notice a change. Could breathing change thinking?
A link between respiration and brain activity has been known since work in the hedgehog by Nobel Laureate Edgar Adrian in 1942. The act of breathing is also strongly linked with olfaction. Considerable study of other mammalian species suggests that inspiration can regulate cortical rhythms of neuronal firing in regions affecting emotion, memory, and behavior.
While these linkages have been shown in many other species, evidence in humans has been lacking, largely due to the invasive nature of the measurements needed. It's also been unknown if the reciprocal effect--where breathing can actually change brain rhythms--can be seen in us. Enter the work of Christina Zelano and colleagues at Northwestern University in Chicago. Their paper "Nasal Respiration Entrains Human Limbic Oscillations and Modulates Cognitive Function" is published in the Journal of Neuroscience and contains the first evidence of breathing on brain in humans.
Zelano and colleagues studied a group of participants undergoing exploration for solutions to intractable epilepsy. This allowed collection of intracranial electroencephalographic (EEG) recordings from indwelling electrodes in the brain surface. Changes in brain activity were collected along with features of breathing. A clear link between EEG rhythm and breathing was found for breathing through the nose, but not for mouth breathing. This activity was largely related to regions in the brain related to olfaction, emotion and memory, including the amygdala and hippocampus.
Additionally, the researchers applied behavioral testing to assess how much changes in neural activity related to other actions. They found enhancement of fear discrimination and memory function related to nasal breathing during inspiration. This work suggests a strong and reciprocal relation between breathing and brain activity in humans.
Deep breathing through the nose is a fundamental part of many meditative practices and martial arts traditions. The focus there is on calming, clarifying, and emptying the mind to focus on the task at hand. (I discussed related themes on over thinking in "Stop Thinking So Much"). The work by Zelano and colleagues provides a mechanistic understanding of just how this might work.
Research remains on further clarifying the link between breathe, brain, and emotion. In the meantime, though, while you are out and about this holiday season please remember to take a few deep breaths in through the nose. It really will help you think more clearly and calmly.
(c) E. Paul Zehr (2016)