Those of you for whom Psych. 1 is a dim memory may be surprised at the current state of personality theory. Robert McCrae’s five-factor model has, since its debut in the 1980s, become the dominant theoretical framework for research into personality.
Extraversion, agreeableness, conscientiousness, neuroticism, and openness to experience are now regarded as the major dimensions of personality. They are quantified in a questionnaire that comes in a long or short version. Each factor is a cluster of traits that tend to occur together. For example, people who score high on the extraversion factor tend to be sociable, cheerful, energetic, and assertive.
The five dimensions transcend culture and upbringing, according to a highly cited 2005 study by McCrae that spanned 50 different cultures. Extraverts, introverts and the rest are found in all cultures, a finding these traits speak to the deeply biological roots of personality.
It has also become apparent that people can accurately judge another’s personality from a brief interaction, from a video clip of behavior, or even from a photograph. The ability to use non-verbal cues to infer personality led a trio of Polish psychologists to speculate that body odor might also contain useful cues.
They designed a clever experiment based on the now-standard smelly T-shirt technique. Thirty men and thirty women—the odor donors—filled out the long version of McCrae’s test plus a test of social dominance. They then wore a T-shirt to bed for three nights in a row, while avoiding perfume, cigarettes, etc. The shirts were put in frozen storage until being rated by a panel of odor judges.
The judges were 100 men and 100 women, each of whom evaluated 10 shirts apiece. They guessed the age and sex of the odor donor, and rated the donor on the Big Five factors plus dominance.
The €64,000 question was this: how well did the average odor-based personality rating match up to the self-reported personality traits of the odor donors?
The answer: pretty damn well.
The main finding . . . is that a few personality traits can be assessed with some degree of accuracy based on olfactory cues. For all assessments of all donors, the correlation between self-assessed personality traits and judgments based on body odour was strongest for extraversion, neuroticism and dominance.The authors note that olfactory evaluations of extraversion and neuroticism were as accurate or more accurate than evaluations in other studies based on viewing behavior on video. Not bad for a quick sniff of a soiled T-shirt.
Odor judges also performed significantly above chance in guessing the sex and age of the odor donor. Interestingly, when it came to guessing the sex of the odor donor, women did better with shirts worn by men than with shirts worn by women; men showed the opposite result. Seems like everyone’s noses are tuned for mating.
The study discussed here is “Does personality smell? Accuracy of personality assessments based on body odour,” by Agnieszka Sorokowska, Piotr Sorokowski, and Andrzej Szmajke, published in the European Journal of Personality, 2011; DOI 10.1002/per.848