By PT Staff, published on November 1, 2007 - last reviewed on April 22, 2012
For Rachel Herz, nothing is sweeter than the smell of… skunk. Herz traces this strange predilection back to a car ride one balmy summer afternoon when she was 5. "The sun was shining, the cicadas were singing, everyone was in a good mood, and the wind blew warm against my face," the Brown University neuroscientist recalls. When an unfamiliar odor wafted into the car, her mother exclaimed, "I love that smell!" In that instant, an emotional link was forged between the happy experience of the car ride and the distinctive aroma of skunk.
While people within a culture often share common associations with particular scents, smells also frequently lead to idiosyncratic responses, Herz observes in her new book, The Scent of Desire. But what's universal—and almost universally underrated—is the wide-ranging impact of smell on our daily lives.
"Scents can have positive effects on mood, stress reduction, sleep enhancement, self-confidence, and physical and cognitive performance," says Theresa Molnar, executive director of the Sense of Smell Institute, the research and educational arm of the perfume industry's Fragrance Foundation. By becoming more aware of the way specific odors affect you personally, you may be able to enhance your health and well-being.
An odor has no personal significance until it becomes connected to something that has meaning, Herz says. With your initial encounter, you begin forming nerve connections that intertwine the smell with emotions. The capacities for both smell and emotion are rooted in the same network of brain structures, the limbic system. The olfactory center also interacts directly with the hippocampus, a brain area involved in the formation of new memories. "No other senses have this kind of deep access," Herz says.
On a practical level, that means that you may be able to use your sense of smell to prompt your memory when taking a test. Herz's research suggests that your ability to recall information may be improved by inhaling an odor you breathed while absorbing information—so fire up a stick of incense while studying, then bring a vial of that aroma's essential oil to a big test.
You also can use smells to evoke a loved one during periods apart. Herz suggests sniffing a reminder of that individual—perhaps a used T-shirt or the person's cologne. "A smell reminder can really conjure the person, more than just looking at a photo," she says. "You actually get the feeling of the person from the smell."
Given the intimate interconnections between smell and emotion, it's not surprising that a glitch in one can contribute to problems with the other. Anosmia—complete loss of the sense of smell—often leads to depression. Conversely, people with severe depression often show a diminished sensitivity to odors.
A decline in the ability to smell may be an early signal of neurological disorders such as Parkinson's, Alzheimer's, and Huntington's diseases. The reverse may also be true. "Theoretically, practicing one's sense of smell could be associated with better neurological well-being, but this has not been proven," says Christian Kohler, clinical director of neuropsychiatry at the University of Pennsylvania. Still, you have nothing to lose by giving your nose a regular workout.
As a significant link in the mind-body connection, the sense of smell can be deployed to improve pain tolerance. Any pleasant smell can act as a distraction and lift mood, but recent studies suggest that sweet smells may work best. "Sweet tastes reduce pain by activating opioid systems in the brain, and the odor comes to activate the same systems," says Australian psychologist John Prescott, currently a visiting scholar at Oxford University.
You can also use your sense of smell to deliver instant relaxation, says Pamela Dalton, a sensory psychologist at the Monell Chemical Senses Center, in Philadelphia. Pick a distinctive odor, then pair that aroma with a calming meditation session. After a few sessions, the odor itself will elicit a relaxed state, even when you don't have time to meditate.
The smell savvy that helps you perform better on a test or cope more effectively with pain also helps you shape the impression you make on others. Choose a personal fragrance carefully, being mindful of common cultural associations. A mossy or woody fragrance exudes earthiness, for example, while a musky scent connotes sexiness.
If you want to be remembered, pick a distinctive fragrance that many people haven't encountered. And don't drench yourself in cologne. Just because your own nose adapts to the scent after 15 minutes doesn't mean customers you greet or friends you meet can't still smell it.
Linda Andrews is a psychology and health writer in Albuquerque, New Mexico.
Aromas have different effects on everyone, but these natural fragrances are odors for the masses.
Peppermint is generally invigorating. "Peppermint scent increases activity in the brain area that wakes us up in the morning ," says Bryan Raudenbush, a psychologist at Wheeling Jesuit University in West Virginia. His research has shown that exercisers run faster and do more push-ups when exposed to the scent. Try a few drops of peppermint oil on a wristband.
Jasmine is a sleep aid. "Our research has shown that the scent of jasmine in your bedroom leads to a more restful night of sleep and a greater level of alertness the following day," Raudenbush says. Other labs have found that the scent increases the brain waves associated with deep sleep. Put some jasmine oil in a bedside aroma diffuser or sprinkle a few drops on your pillow.
Lavender is generally relaxing. Exposure to lavender scent can decrease heart rate. Use the scent for unwinding at bedtime, suggests Avery Gilbert, a sensory psychologist in Montclair, New Jersey. Or take several whiffs to recharge yourself during work breaks. Japanese researchers find that the practice helps prevent an afternoon slump in concentration.
Vanilla abets weight loss. Herz finds that it works as a replacement for the pleasure that you would get from eating sweets—but without the calories. "This is not a scent you would use if you had an empty stomach, because it's likely to just make you hungrier," she says. But if you've had a healthy lunch, it can help curb the craving for a candy bar afterward.