Science Illuminates Why Slow Breathing Calms The Mind

People have been learning to control their breath for a long time—it’s been a method of calming the mind in yoga and meditation for millennia, and it’s used today in medical and psychiatric settings to help quell anxiety, and even curb panic. Now, a study in mice homes in on the brain mechanisms that underlie the calming effect of slow breathing. So even if you don't quite understand or believe in the power of breathwork to calm you, it will very likely benefit your brain anyway.

There’s a small group of neurons in the brainstem, which link breathing to various states—anxiety, excitement, relaxation and attention—and is known as the respiratory pacemaker. It’s known to exist in both mice and humans.

“The respiratory pacemaker has, in some respects, a tougher job than its counterpart in the heart,” said study author Mark Krasnow in a news release. “Unlike the heart’s one-dimensional, slow-to-fast continuum, there are many distinct types of breaths: regular, excited, sighing, yawning, gasping, sleeping, laughing, sobbing. We wondered if different subtypes of neurons within the respiratory control center might be in charge of generating these different types of breath.”

Krasnow and his team wanted to tease apart the discrete subgroups of cells within the cluster, which might each control a different type of breathing—so they decided to try to knock out one type at a time. The group has been able to isolate the genes and proteins for each type of cell, and developed a way to selectively silence them. In an earlier study, they isolated the cells that are responsible for sighing—when the cells’ activity was suppressed, the animal lost its ability to sigh.

In the new study, they found another subset, which they were able to knock out and observe the effects of. When they watched the mice who'd had this group of cells quieted, however, nothing obvious changed in their breathing—that is, until they put the mice in a new environment, and saw that they weren’t exhibiting the kinds of active exploratory sniffs that you’d expect. This tipped the team off that they may have hit the “calm” area of the breathing cluster. “If you put them in a novel environment, which normally stimulates lots of sniffing and exploration,” said grad student Kevin Yackle, “they would just sit around grooming themselves.” Which made the team think they had indeed hit the calming subgroup of neurons.

And at the heart of the animals’ calm was where the cells from this area projected: the team found that the cells send fibers to brain area that govern wakefulness and arousal. This particular sub-area “appears to play a key role in the effects of breathing on arousal and emotion, such as seen during meditation,” said author Jack Feldman, who made the initial discovery in the early 1990s. “We’re hopeful that understanding this center’s function will lead to therapies for stress, depression and other negative emotions.”

It's good to understand why such a simple and long-practiced activity has the effect it seems to have on higher-order brain function—since it's our "higher" thinking that typically gets us into trouble. Breathing may be one of those things that you don’t need to fully understand or even believe in for it to work. So even if you don’t think the practice will do much to calm your brain, give it a try—it probably will help you in spite of yourself.