Could inhaling be a linchpin of cognition?
Olfaction is vital to survival, from finding food to avoiding predators. Now, a group of Weizmann Institute neuroscientists, led by Prof. Noam Sobel in the Department of Neurobiology, have shown that the very act of nasal inhalation can help us think better.
His lab recently published a study showing that our olfactory system may shape the evolution of brain function well beyond the basic way in which most of us think of the utility of our noses and airways in terms of smelling and breathing. The scientists determined that inhaling, in particular, assists with problem solving—a concept, Prof. Sobel points out, encapsulated in the word “inspiration,” which means both to breathe in and to move the intellect.
Decades of research have indicated that the unique anatomy of the olfactory system supports a strong ‘odor-emotion-memory’ connection—that is, unlike all other sensations, smell input doesn’t relay first through the thalamus before getting to the cortex; it goes directly into the limbic system, a brain region typically associated with emotion and memory processing.
Olfaction is the most ancient sense to have evolved among terrestrial mammals such as humans. Scientists have theorized that due to its primacy among other sensory functions, olfaction effectively ‘set the tone’ for subsequent brain development and sensory processing. Prof. Sobel has pushed that notion further. He hypothesized that inhalation, in and of itself, might prepare the brain for cognition—in essence, priming the brain to receive input. We think better when we’ve inspired.
Synchronized sniffing spells success
To test this hypothesis, the Sobel laboratory had study participants perform non-emotional cognitive tasks while the scientists measured nasal airflow and recorded brain activity via electroencephalography (EEG). The scientists found that participants unconsciously tended to time the onset of their cognitive efforts to coincide with nasal inhalation. When the pattern-matching task—the simplest task—was covertly timed to coincide specifically with participant inhalation or exhalation, the results were even stronger: Inhalation at task onset was associated with improved performance.
The study was published in Nature Human Behaviour in March.
“Our results show that it’s not only the olfactory system that is sensitive to inhalation and exhalation—the entire brain is,” says Prof. Sobel. “We could generalize to say that the brain works better with inhalation.” Moreover, the nose truly knows, as synchronized inhalation through the mouth had no impact on cognitive performance.
While the benefit of synchronizing one’s breathing patterns to a person’s activity is well-known to athletes and yogis, the benefits to cognition are less well appreciated. Now, Prof. Sobel proposes that inhalation may drive patterns of neural activity consistent with heightened attention, thereby optimizing information processing: if we breathe better, we will think better. This study may point the way towards the development of breathing exercises to improve learning and concentration, and methods to help both children and adults with learning and attention deficit disorders.
Prof. Noam Sobel’s research is supported by the Azrieli National Institute for Human Brain Imaging and Research; the Norman and Helen Asher Center for Human Brain Imaging; the Nadia Jaglom Laboratory for the Research in the Neurobiology of Olfaction; the Fondation Adelis; the Rob and Cheryl McEwen Fund for Brain Research; and the European Research Council. Prof. Sobel is the incumbent of the Sara and Michael Sela Professorial Chair of Neurobiology.