Nasal breathing may enhance your memory new research finds.
Humans have long proposed a connection between how we breathe and our state of mind. In fact, modern lore tells us that breathing in deeply is the pathway to relaxation and mental peace. But does the scientific evidence back that up?
A growing number of studies are now examining whether breathing affects cognition. One such study published in October in the Journal of Neuroscience looked at whether how we breathe affects what we remember.
Being able to recognize odors is a key survival mechanism for humans and most animals. Smell smoke and we know there’s fire. That’s why neuroscientists believe that nasal breathing and early evolutionary adaptation are directly linked.
Studies show that when mice sniff, the flow of air stimulates brain cells in the smell center in what is known as the olfactory bulb. This, in turn, activates cells in the hippocampus, the brain region responsible for encoding, storing and retrieving memories.
In the October study, researchers at the Karolinska Institute in Sweden and colleagues elsewhere conducted a study to see if this also applies to humans. They asked two dozen young men and women to sniff 12 different familiar and unfamiliar scents from small vials and memorize what they smelled.
This happened twice. On the first occasion participants sat quietly for an hour immediately after sniffing the scents and had their noses clipped shut to prevent nasal breathing. On the second trial the same volunteers sat for an hour with their mouths tapes to prevent oral breathing. Researchers proposed that during that quiet hour, memories of the smells would be stored in the subject's hippocampus.
To test the theory, after each resting hour these same individuals were exposed to the original scents as well as some new ones, then asked to report whether they’d encountered the odor in the previous trial.
Results showed that both men and women were consistently better at identifying smells when they breathed through their noses during the quiet period. Mouth breathing was linked to more incorrect answers and less precise scent recall.
The researchers believed this occurred because nasal breathing enhanced the consolidation of memories, whereas mouth breathing did not. This is likely because the olfactory bulb was bypassed during mouth breathing, so the hippocampus wasn’t activated as powerfully.
Although this study doesn’t tell us whether a practice of nasal breathing will give us a better memory, it does suggest that how we breathe makes a difference in how our minds work. What’s more, it supports the premise that respiration is directly linked to core cognitive functions like memory.
So you may want to try breathing through your nose from now on.