Oct. 24 (UPI) -- According to a new study, nasal breathing can boost memory consolidation.
Study participants who breathed through their noses for an hour after being exposed to a variety of odors were better able to recall and identify the odors than participants who breathed through their mouths.
Researchers in Sweden were inspired by previous studies revealing the impacts of sniffing on the human brain, as well as animal studies showcasing the impacts of breathing on brain activity.
"The present study specifically builds on several recent animal studies showing that breathing affects the whole brain, and especially the memory networks in a rhythmical manner," Artin Arshamian, researcher at the Karolinska Institute in Stockholm, told UPI in an email.
One previous study showed nasal breathing in mice influences neural pathways liked with memory consolidation.
"We set out to test if nasal breathing, as compared to mouth breathing, actually had an impact on the consolidation of memories," Arshamian said.
Memory consolidation is the process used by the brain to convert short-term memories into long-term memories.
For the experiment, Arshamian and his colleagues had nose-breathers tape their mouths during the hour-long consolidation period. Both mouth-breathers and nose-breathers were tested on their ability to recall various odors. The exposure and tests phase featured odors that were familiar and easy to name, as well as smells that were foreign and had unfamiliar names.
The recognition test proved nasal breathing helped participants recall the names of both familiar and unfamiliar odors.
While no brain imaging was used, scientists believe nasal breathing enhances the links between sensory centers in the brain and the neural regions used for memory consolidation.
Scientists aren't yet sure if nasal breathing benefits the consolidation of memories unrelated to the olfactory system.
"It is still unknown if nose breathing affects language networks. That is something we want to find out," Arshamian said. "We do not know how specific this effect is but we believe that it should affect a wide range of memories."
Researchers hope followup studies will further illuminate the link between breathing rhythms and brain activity.
"We should not be surprised if it has very fundamental effects stretching far beyond basic oxygenation," Arshamian said. "Breathing as a ritual practice is an important aspects in many cultures. For example, in Buddhist meditation, practitioners have manipulated breathing to alter behavior for thousands of years."
Arshamian and his colleagues shared thy investigation of nasal breathing and memory consolidation in a new study published this week in the Journal of Neuroscience.