The Science of Scent

Fragrance Flashback

Wonder why the scent of firewood reminds you of summer camp or how a whiff of Goldschläger can still turn your stomach—nearly 20 years later? It's all in your head, literally. Scent is processed in the brain's limbic system, where emotion and memory also occur. "Consequently, there's a lot of cross-talk between these areas," explains William Horgan, CEO of Human Pheromone Sciences.

Sniff Test

Something you never expected to read in a beauty story: When the U.S. military set out to make a stink bomb, it struggled to find a scent that was universally putrid. Experts say that most pleasant and unpleasant odors are learned, not hard-wired into the brain. "Two people may smell the same fragrance differently because of the emotions that are evoked by the scent," says Sephora fragrance expert Amy Cuadra. "In the fragrance world, the concept is called 'imprinting.'"

Going Gaga

Your mother's pregnancy induced ice cream cravings could have shaped your preference for sweet scents. Still in the womb, a fetus develops an affinity for certain smells based on the diets of moms-to-be, according to a study from University of Colorado School of Medicine. And by two weeks, an infant can sniff the difference between Mom's breast milk and another woman's.

Scent Of A Woman

Initially, fragrances were used to mask certain "human" odors. But now that we bathe on a regular basis (hopefully), women tend to use fragrances to enhance—not hide—how they smell. Researchers have found a connection between the scents we prefer and our own natural scent, which is based on individual genetics.

Opposites Attract

Like other mammals, we sniff out potential partners, getting info on their immune system from scent, say experts. (And in the subconscious world of matchmaking, different immune systems mean healthier offspring.) In what is known as the sweaty T-shirt test, women preferred the scent of tees worn by men whose immune system genes were unlike their own. If you're having doubts in your relationship, then smelling the dirty laundry might help.

Sixth Sense

More and more, perfume-makers are adding synthetic pheromones to heighten a scent's emotional impact. Although odorless, these chemicals may help trigger certain positive feelings. Paired with perfumes, the two work in tandem to boost your mood, which in turn can affect how others see you. "When a pheromone elicits an emotion," says Horgan, "the concurrent scent will be stored in your memory with that emotion."

SEARCH: Which fragrances have pheromones?

Shop Around

You may not have a degree in neuroscience (yet!), but now that we have an understanding of how scents work, the trick is to find one that works for you. For fragrance beginners, "It's a good idea to start by testing scents on blotter strips," says fragrance expert Jan Moran. This will help you eliminate definite dislikes, but to truly find just the right a fragrance, you'll have to eventually test it on your own skin.