Smell is such a strong trigger of memory that merely catching a whiff of something innocuous can elicit a feeling of nostalgia or longing. But as it turns out, that’s not the case for every stage of life.
In a recent study conducted by Aarhus University in Denmark, scientists found that there’s a huge discrepancy between the scents that adults can identify and those that adolescents recognize.
By exposing 411 adolescents and 320 adults to 125 different odours, the results showed that teens were less able to identify smells like spices, vegetables, fruit and, alarmingly, sweat.
“We perceive the world through our senses, and exposure has a major impact on odour familiarity,” says Alexander Fjaeldstad, lead author of the study and PhD student in the Department of Psychiatry at the University of Oxford. “In a time where we are constantly bombarded with sensory stimuli like television, smartphones and tablets, there is an increased demand for the ability to prioritise which sensory inputs should receive attention.”
In other words, even if the peach emoji is one of the most popular on smartphones, until there’s a scratch and sniff app that emits the smell of the fruit, teens will have difficulty identifying it.
Interestingly, teens were quick to identify sweet foods like cookies, marshmallows and candy, which leads researchers to believe that our sense of smell develops as we are more exposed to certain scents.
“There was an age-dependent correlation between familiarity of odours giving us high energy, like sweet foods and candy, where adolescents were better,” Fjaeldstad says. “Conversely, odours of foods ensuring long-term well being that are a part of a balanced diet were more familiar when individuals were in their 20s or older.”
While adolescents easily identified scents like coffee and cigarettes (possibly due to cumulative exposure), they had a lot more difficulty with acrid foods like lemons and mustard, and environmental smells like sweat.
“Though odours are potent triggers of autobiographical memories from as far back as the first decade of life — and in a way closely linked to memory — the ability to name odours is an acquired skill that takes years to master and requires both perceptual and verbal training,” Fjaeldstad writes in the study.
This could go a long way to explaining why teens need to be told to wear deodorant or change their socks. It also explains how certain professionals, like sommeliers and baristas, can refine their sense of smell through study.
For roughly five per cent of the general population, this wouldn’t even factor in as they qualify as anosmic, which means they have no sense of smell. Another 15 per cent are hyposmic, or have a lowered sense of smell.