The first condition of understanding a foreign country is to smell it. — Rudyard Kipling
With the winter, comes one of the most annoying things in life: the stuffy nose.
But more than a nasally voice or the inability to sleep comfortably (if at all), losing your sense of smell can have effects on your psychology. Or rather, in detecting the psychology of others…
Likely, you’ve heard it claimed “dogs can smell fear,” but did you know humans can, too?
Researchers who study chemosignaling (i.e., how the odors of the body communicate information to others) have found that humans can detect a variety of emotions in another person from their scent alone.
For example, one team of researchers had participants place sweat absorbent pads under their armpits while watching a 25-minute video meant to elicit fear (e.g., scenes from The Shining) or disgust (e.g., scenes from MTV’s Jackass). These samples were then refrigerated and stored for later participants who had the pleasure of getting to smell them.
Cutting strips from the original sample, researchers had a new batch of participants sniff them, while researchers used facial, eye, and brain tracking measures to see how they responded to them.
Amazingly, when participants smelled the pads that came from watching scary movies, both facial muscles and brain activation mirrored that of people who were actually scared. As well, eye tracking revealed that they were more likely to scan their visual surroundings (as those in fear need to survey their environment for the threat).
Those who sniffed the “disgust pads,” on the other hand, showed both facial and brain activation of those who have encountered something disgusting. And eye tracking revealed that these participants actually refrained from looking around (as those disgusted try to look away from the revolting stimuli—or at least reduce their exposure to it).
Moreover, other research has even shown we can detect positive emotions through chemosignaling, too! Similar to the prior procedure, researchers collected sweat samples from those watching happy clips (e.g., the “Bear Necessities” scene from The Jungle Book) and had later participants smell them.
And again, they saw facial and brain data consistent with people who are happy.
Interestingly, across all of the studies, participants were never able to consciously acknowledge the effects of the chemosignaling. Rather, these processes were having their effect at subconscious levels.
But if you thought that was impressive, wait till you hear this: participants were able to sniff out personality traits of other participants as well!
In previous posts, we’ve discussed how participants were able to assess another’s personality from watching a mere five second, silent clip of someone. However, in this research, all the participants had to go off of was a cotton shirt the person had been wearing for three days.
In this study, researchers had a first batch of participants wear a standard white undershirt for three days and then afterward, respond to some personality measures about themselves. Later, the researchers brought in 200 participants to come smell those shirts and guess at the person’s personality.
Remarkably, participants were able to determine—above chance level—people’s self-rated levels of extraversion, emotional stability, and dominance from smell alone.
So, the next time someone gives you a weird smell, remember, you don’t have to have a nose as big as mine to use that information in evaluating them.
Psychophilosophy to Ponder: Typically when we evaluate others, we rely on sight and sound exclusively for these assessments. But after today’s post, you know that smell can also play a critical role in those determinations. In what other ways do you overlook smell in daily live? For example, how could the smell of your house influence your mood? How could the smells of a nearby restaurant influence what you want to eat? We have multiple senses for a reason, so try not to exclude those that aren’t only sight and sound!
de Groot, J. H., Smeets, M. A., Kaldewaij, A., Duijndam, M. J., & Semin, G. R. (2012). Chemosignals communicate human emotions. Psychological science, 23(11), 1417-1424.
de Groot, J. H., Smeets, M. A., Rowson, M. J., Bulsing, P. J., Blonk, C. G., Wilkinson, J. E., & Semin, G. R. (2015). A sniff of happiness. Psychological science, 0956797614566318.
Sorokowska, A., Sorokowski, P., & Szmajke, A. (2012). Does personality smell? Accuracy of personality assessments based on body odour. European Journal of Personality, 26(5), 496-503.