Strong smells -- researchers measure impact of aromatherapy

April 14, 2000
Web posted at: 3:10 p.m. EDT (1910 GMT)

From staff reports

ATLANTA (CNN) -- Americans spend millions of dollars each year on candles, incense and oils in search of pleasing aromas to improve mood or to enhance physical and emotional well-being.

Does it work?

According to Dr. Alan R. Hirsch of the Smell & Taste Treatment and Research Foundation, Chicago, "The quickest way to change a mood state -- quicker than with any other sensual modality -- is with smell."

Hirsch and his colleagues have studied aromatherapy for 15 years. They have concluded that specific odors can change your mood and behavior. This process depends on conveying odoriferous particles through air or in water, then a complex mental reaction.

"We found that mixed floral smells effect the speed of learning," said Hirsch. "Green apples tend to reduce migraine headaches. Lavender tends to induce relaxation -- as does vanilla."

As further evidence of the aroma-mood connection, Dr. Charles J. Wysocki of the Monell Chemical Senses Center, Philadelphia, said, "There are other sorts of physiological changes one can measure -- blood pressure, for example, heart rate, body temperature. These things are all correlates of changes in mood and emotion."

Research findings at the Monell center show that "odors are often thought to provide the best memory cues because some of our oldest and most emotionally laden memories are associated with odors. ... Accuracy of a memory is not affected by the type of sensory cue, for example, whether it is olfactory or auditory. Instead, a memory that is triggered by an odor is experienced as being more emotionally intense and evocative than a memory triggered by any other type of sensory cue."

Research has also shown odors help people remember. "Memory is enhanced when learning takes place in the presence of a novel odor, and is further facilitated if learning occurs during a heightened emotional state," according to the Monell center.

Although some aromas are so subtle they donāt register consciously, the nose and brain can detect 10,000 or more different odors. A question still under study is whether smelling particular odors to enhance emotional or physical healing depends on the personās belief that aromatherapy "works."

Paul Johnson, a writer and skeptic of paranormal claims, has noted that aromatherapy is "a belief that the essential oils of various flowers have therapeutic effects. These effects are psychological rather than physical, and so itās a bit difficult to define what we mean by a statement that Īit works.ā After all, if people do it and feel better, then that is a real effect, whether it occurred because of suggestion or because the flowers contain a powerful psychoactive drug."

Monell Chemical Senses Center
Smell & Taste Treatment and Research Foundation

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