Scientists have long known that breathing and emotional state are closely connected. What this study adds is a surprisingly detailed look at one way that connection may work. In mice, researchers traced a pathway from sensory neurons in the nose through the olfactory system and ultimately to the amygdala, where changing the frequency of nasal airflow altered anxiety-like behavior.

The discovery offers a compelling biological explanation for why slow nasal breathing may feel calming, but there is still an important gap between mapping this circuit in mice and using it to treat anxiety in people. The researchers used only male mice and highly controlled experimental techniques, and the same pathway still needs to be confirmed in humans.

Still, the findings add to a growing picture of breathing as more than something that simply changes when we’re anxious. The signals created by breathing itself may help shape what happens in the brain. If future human research confirms the same pathway, something as ordinary as breathing through the nose could give scientists a new window into how the brain regulates anxiety.