A study finds that the rhythm of your breath can influence brain activity that enhances memory recall and emotional experience.
Breathing doesn't just keep you alive. Research shows that it is directly linked to brain function and behavior.
For the first time, a team of scientists Northwestern Medicine have discovered that the rhythm of breathing creates electrical activity in the brain that enhances emotional judgments and memory recall. These effects depend on whether you inhale or exhale, and whether you breathe through the nose or mouth.
In the study published in the Journal of Neuroscience, participants identified a fearful face more rapidly while inhaling than exhaling. They were also were more likely to recall an object when they encountered it while inhaling than exhaling. The effect disappeared when individuals breathed through the mouth.
The researchers first noted these differences in brain activity during a study of seven patients with epilepsy who had been scheduled for brain surgery. A week prior to surgery, a surgeon implanted electrodes into these patients’ brains in an attempt to locate the origin of their seizures. The electrical signals that they recorded indicated that brain activity fluctuated with breathing. Specifically, this activity occurred in brain regions where emotions, memory and smells are processed.
This revelation led scientists to ask whether fear processing and memory, which are associated with these brain regions, might be affected by breathing.
The amygdala is a region in the brain's limbic system known to be associated with emotional processing. It is particularly active during fear-related emotions.
To examine the links between breathing rhythm and amygdala activity, the researchers asked approximately 60 participants to rapidly identify the emotional expressions in a series of pictures of faces expressing either fear or surprise while simultaneously recording their breathing.
When faces were encountered during inhalation, individuals tended to identify them as fearful more quickly than when the faces were viewed during exhalation. This was not the case when observing faces expressing surprise. Interestingly, these effects were reduced when participants performed the identical task while breathing through their mouths.
This means that individual's ability to identify fearful faces more quickly only occurred while breathing through the nose.
The same participants then performed in a test of memory function, which is associated with activity in the brain's hippocampus. Here they were shown images of objects on a computer screen and asked to remember them. They were subsequently asked to recall these objects.
Results of their performance showed that participants recalled the objects more efficiently if they were observed during inhalation. This implies that we may be better at recalling an object if we encounter it while breathing rapidly, which may have particular survival value when encountering danger.
In an interview with Neuroscience News, an author of the study, Christina Zelano speculated, “If you are in a panic state, your breathing rhythm becomes faster. As a result you’ll spend proportionally more time inhaling than when in a calm state. Thus, our body’s innate response to fear with faster breathing could have a positive impact on brain function and result in faster response times to dangerous stimuli in the environment.”
Practices such as yoga and meditation focus on observing or changing the rhythm of the breath as a means of altering cognitive and emotional experience. Future studies that examine the impact of focused breathing may help to shed additional light on the direct links between breathing and lived experience.
Source
Zelano C, Jiang H, Zhou G, Arora N, Schuele S et al. (2016). Nasal Respiration Entrains Human Limbic Oscillations and Modulates Cognitive Function, Journal of Neuroscience. doi:10.1523/JNEUROSCI.2586-16.2016