When it comes to coping with scary or stressful situations, mental health experts have long given a simple piece of advice: Take a deep breath in through the nose, and out through the mouth. Now, new research suggests that this particular breathing technique really does impact brain activity—and can even improve your memory.
Northwestern University researchers recruited about 100 young adults, some of whom were asked to make snap judgments about facial expressions that flashed quickly across a computer screen. Breathing did affect their performance: When people were inhaling through their noses, they were able to recognize faces expressing fear faster than when they were exhaling. In another test, researchers looked at participants' ability to remember objects flashing on the screen. Here, too, they were more likely to remember objects if they encountered them during inhales, versus during exhales.
When mouth-breathing, all these effects disappeared.
The new study is the first to show that the rhythm of breathing creates electrical activity in the brain, according to the report, which was published in The Journal of Neuroscience.
“Our data is preliminary, but exciting,” says lead author Christina Zelano, PhD, assistant professor of neurology at Northwestern University Feinberg School of Medicine, to Health. “And though it is too preliminary at this stage, it has the potential to lead to some deliberate breathing strategies for cognitive enhancement.”
She says that one of the study’s major findings is that nasal inhaling causes a “dramatic difference” in areas of the brain related to emotional processing (the amygdala) and memory (the hippocampus), compared with exhaling.
Researchers discovered that when you breathe in, you're stimulating neurons in the olfactory cortex, amygdala, and hippocampus, all across the limbic system.
Future studies on this topic may help explain the well-documented psychological benefits of meditation and focused breathing, says Zelano, which can essentially synchronize brain oscillations across the brain’s emotion center.
The findings may also offer a clue as to why our breathing tends to speed up when we’re scared or panicked. “As a result, you’ll spend proportionally more time inhaling than when in a calm state,” Zelano says. This could affect brain function, she adds, “and result in faster response times to dangerous stimuli in the environment.”
In fact, Zelano thinks we may even be able to use this knowledge to our advantage. “If you’re in a dangerous environment with fearful stimuli, our data indicate that you can respond more quickly if you are inhaling through your nose,” she says.
Of course, this study is just a first step. Whether we can truly use our breath to enhance or control our fear response—or our memory, for that matter—remains to be seen, says Zelano.