Sorting out when smells start shaping our emotional state
There’s nothing like the smell of freshly baked cookies. A whiff of your favorite recipe can be enough to improve your mood and remind you of the memories associated with the tasty treats, thanks to our brain’s olfactory bulb’s direct connections to the amygdala, where much of our emotional processing takes place. The most common exception to this phenomenon is if you encounter the smell of cookies you’ve never had before, because all these strong responses to smells are learned through experience. The other exception is, apparently, if you’re under five years old.
140 kids participated in an experiment looking at how much they associated emotional responses with specific smells. They were first given a sniff of a rose, stinky fish, or nothing, possibly priming their emotional state. They were then shown two photos of a person making either a happy or disgusted face, and asked to pick one. Most kids and adults would be more likely to pick a happy face after smelling a rose, and a disgusted face after smelling the fish. Kids under five, however, didn’t seem to make these connections. Instead, they picked the happy face no matter what odor they’d just smelled.
Smiling about stinky fish
It’s possible that these kids just hadn’t had a chance to associate the smell of rotting fish with feelings of discuss, but researchers are wondering if there may be a developmental factor at play here as well. In addition to connecting to our emotion-driving amygdala, our olfactory bulb also connects to the hippocampus, which helps record and associate memories. It’s possible that these connections aren’t as well established before age five, and thus even if these younger children had learned that fish can be unpleasantly stinky, their brains weren’t ready to put that experience together with the emotion seen in the images.
To further test the dynamic between emotional recognition and smell, researchers plan to repeat this study with autistic children. They want to see if emotional states associated with smells can be paired with social cues, like smiling faces. Aside from further clues about how these connections develop in our brains, it may offer new avenues to share emotional information with people who otherwise have difficulty reading social signals from the people around them.