Social influences set expectations, and opinions, of smells before we sample a scent

What smells do you like? Vanilla extract maybe? The air before a rainstorm? Fresh coffee grounds?

Are you sure about that?

Smells can trigger powerful responses in us, and have can trigger strong, specific memories in a way that other sensory information doesn’t. It would seem like these connections would make our sense of smell somewhat immutable, but it turns out that they can’t stand up to social pressure. If we see that other people are happy or disgusted right before we sniff something, we adjust our opinions to match theirs, even if those people are only seen in photographs. Even if you like the smell of vanilla, seeing a disgusted face might make it a bit less pleasant than you usually think.

Opinions before odors

Previous research had made a link between social influences and our opinions of smells, but this new research actually pieced together the timeline of how this all works. Participants viewed photos of people with happy, neutral or disgusted expressions on their faces while their brain activity was tracked in an fMRI machine. After seeing the face, they were exposed to a smell like lemon or sweat, and asked to rate how pleasant they found that smell. Activity was detected in the piriform cortex, which makes sense as it plays a role in how we perceive smells. The catch was that this activity started before participants smelled anything— the photos apparently created expectations about the smell, and that strongly shaped what they actually perceived.

So your peers’ reactions to the smells in your world may be changing how much you enjoy the scent of onions or cut grass, but this influence does have its limits. Even if everyone around you smiles their hardest, one smell that your brain isn’t going to let you like is feces. Presumably other biologically hazardous items like vomit retain their repulsion, since there’s basically no save way for peer pressure to convince us to like the smell of poop.

Source: How The Emotions Of Others Influence Our Olfactory Sense, Scienmag