We Can Recognize Our Own Scent

Before this, it wasn’t clear how people would react to their own smell or even whether they could recognize it.

Photo: Bradleygee

Everyone has their own scent—just think of how differently your grandma and your boyfriend smell when you lean in for a hug. But can we smell ourselves? For the first time, scientists show that yes, we can, ScienceNOW reports.

Our basis of self-smell originates in molecules similar to those animals use to chose mates. Humans use these molecules, called histocompatibility complex proteins, to help differentiate between people and between our own cells and invading pathogens. These peptides were featured in the now-famous “smelly T-shirt” experiment in which researchers asked women to sniffed men’s worn shirts and identify which they preferred. The women tended to select the men’s scents that least like their own smells. But that experiment didn’t reveal how people react to their own smell or even whether they could recognize it.

In this latest experiment, biologists tested whether women can recognize lab-made proteins resembling their own. After taking a shower, the researchers asked the women to apply two different solutions to their armpits and decide which smell they liked better. Women who were nonsmokers and who did not have a cold preferred the solution closest to their own scent.

Next, the biologist used fMRI to measure brain changes in women while they smelled various solutions. Again, the women responded differently to the self and non-self smells. A particular region of the brain activated only when the women’s “self” peptides came into contact with their nose.

These findings may explain how we choose a perfume or cologne. People might select a scent that amplifies their own peptides’ smell, while still being able to appreciate other scents on other people. Chanel No. 5 may mesh well with your own body odor, while your best friend may be better suited for patchouli oil.

More from Smithsonian.com:

The First Major Museum Show to Focus on Scent 
Why Do Flowers Smell Good? 

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