The best smell for your brain: the science of olfaction and emotion

What comes to mind if I ask you to imagine that you are at the following places: 

• a bakery,
• a candle store,
• a hospital,
• a rose garden,
• a perfume counter? 

One of your associations is likely to be the sensation of smell because all of the places above have strong aromas.  Does it feel like you can almost smell them?  Those aromas can quickly change your moods and emotions, and evoke memories.  Why do odors play such a significant part in our emotional regulation?

The sense of smell is the only one of the five senses directly linked to the limbic system – the center of emotions in the brain.  According to "Essential Oils Desk Reference," when we inhale a fragrance, the odor molecules travel up the nose where they are trapped by olfactory membranes, protected by the lining inside the nose.  Each odor molecule fits into specific receptor cell sites. Each one of these hundreds of millions of nerve cells is replaced every 28 days.  When this lining of nerve cells is stimulated by the odor molecules, it triggers electrical impulses to the olfactory bulb in the brain.  The olfactory bulb than transmits the impulses to the gustatory center, responsible for our perception of taste, the amygdala, where emotional memories are stored, and other parts of the limbic system of the brain. 

Alan Hirsch, M.D., F.A.C.P., the founder and neurological director of The Smell & Taste Treatment and Research Foundation, explains this quick connection between odors and emotions in his interview for the medical journal Alternative & Complementary Therapies [PDF]:

What makes the sense of smell unique among the senses is that the brain reacts positively or negatively to an odor before identifying the source of the odor.  That is, a person encounters a pleasing smell and his or her reaction is one of pleasure.  Then, a second later, the person figures out that he or she had smelled lilacs.  Visually, one sees a picture of a tree or a cow and first identifies the subject, and then determines whether or not he or she likes the picture.  This is the opposite of the sense of smell; with smell emotional reaction comes first.

As we all know, smells can also transport us into the past.  In one of his studies, Dr. Hirsch discovered the number-one odor to evoke childhood memories.  Can you guess what it is?

We looked at 989 people from 45 states and 39 countries, and found that the number-one odor that made people nostalgic for childhood was baked goods.  After that, it depended on when and where they grew up.  If they grew up on the East Coast of the United States, the smell of flowers made people nostalgic for childhood.  In the South, it was the smell of fresh air; in the Midwest, the smell of farm animals; and in the West it was the smell of meat cooking or meat barbecuing.

It turns out that environmental smells affect our behavior.  In the same interview, Dr. Hirsch reports that people drive more aggressively on days when there is bad smell of air pollution, causing an increase in motor-vehicle accidents.  Bad environmental odors tend to promote aggression, impede learning, and encourage school kids to misbehave.

I don't know about you, but I am about to diffuse some peppermint oil to improve my environment.  It helps with task performance by increasing concentration, enhances athletic performance [PDF], and curbs appetite [PDF].  Smells good to me!

Related Posts:
Do you smell success?
Want to be a better problem-solver in your dreams?
Orientation Series: 21 Steps to Becoming a Better Learner: Memorizing

To learn more about essential oils:  http://www.smartessentialoils.com

Comments

[Cheryl]

Anastasia
I love your posts. While not immediately relevant to my work, they are very useful for life!

[Anastasia]

Thank you, Cheryl!

And your work makes our lives more brain-friendly :) With our limited working memory capacity, we need plain language!