科学美国人60秒:Nose Knows What the Mind Tells It

They say that the nose knows. But it still gets its marching orders from the brain—at least when it comes to the lungs. Got that? Nose to brain to lungs. Because a new study shows that when people with asthma think they’re smelling something noxious, their airways become inflamed—even when the odor is harmless. The finding is in the Journal of Psychosomatic Research. [Cristina Jaén and Pamela Dalton, Asthma and odors: The role of risk perception in asthma exacerbation] 

Asthma attacks can be triggered by pollen, dust, harsh chemicals or scents. These environmental annoyances constrict the airways in the lung, making breathing difficult. 

In this study, researchers wanted to see whether an individual’s assumptions have any influence over this breathtaking series of events. So they exposed 17 asthma sufferers to a benign chemical that smells like roses for 15 minutes. Nine subjects were told the fragrance was a potential irritant, the other eight that it would be therapeutic.

The results were as plain as the nose on your face: subjects who expected an irritant experienced inflammation. And those who were primed to be soothed had no adverse reactions—even if they were normally bothered by perfumes.

The results suggest that a rose by any other name would smell as sweet. Or be as irritating as you expect it will.

—Karen Hopkin