News

Do You Smell Something

by Don Meyer, Ph.D. | January 30, 2010

Memories, imagination, old sentiments, and associations are more readily reached through the sense of smell than through any other channel.
Oliver Wendell Holmes

I can\'t imagine what it must be like to lose your sense of smell. So many parts of our lives are informed by the way something smells to us. From the smell of food to the smell of perfume, odors help us identify countless realities. 

Diane Ackerman knew this when she said, \"Hit a tripwire of smell and memories explode all at once. A complex vision leaps out of the undergrowth.\" 

Think about the smells of your childhood. Crayons. Onions and radishes. Lebanon bologna. Apple butter. The barn. Top soil. Grease. Horses. My baseball glove. Burning brush. Dried hay and straw. Corn and oats silage. Fried onions. Sweet corn. Burning kerosene lamps. Hogs. Dogs. 

I really could go on and on. And with each odor, as Ackerman said, \"Memories explode all at once.\" Over 50 years disappear and I am back in my childhood. 

The formal name for smell is Olfaction. Scholars disagree as to how our sense of smell works. According to the shape theory, each receptor detects a feature of the odor molecule. Weak-shape theory, known as odotype theory, suggests that different receptors detect only small pieces of molecules, and these minimal inputs are combined to form a larger olfactory perception. 

An alternative theory, the vibration theory, proposed by Luca Turin, suggests that odor receptors detect the frequencies of vibrations of odor molecules in the infrared range of electron tunneling. 

But in spite of all the research still being done, there is no theory that explains olfactory perception completely. I am writing these words sitting next to Evie in aisle 20 on Continental Flight 1676 from Houston, TX to Philadelphia. And though I may not be able to understand smell, I just got an unusual whiff of delicious food. Eight rows ahead of me the flight attendants are serving a delicious smelling treat to everyone on the plane. All of a sudden that smell has made me very hungry. 

In USA Today (July 1, 2009) Molly Birnbaum, in \"Taking Scent for Granted,\" describes the effect of being hit by a car while she was jogging. Her skull was smashed and in one instant she lost her sense of smell. Birnbaum writes, \"Intangible and often ephemeral, the ability to smell is easily ignored and often forgotten in the face of vision, hearing, and touch. Without scent, however, one\'s experience of the world is dimmed.\" 

She goes on to say, \"Flavor is reduced to the salty, sweet, bitter and sour of the taste buds. Food, therefore, is nothing but texture and temperature. Coffee is hot, bitter water. Milk is thick and gummy. Bakeries are indistinguishable from locker rooms.\" 

By the way, the odor of the food I smelled was greater than the quality of the food that came with it: A Stefano \"Turkey Dog,\" a tossed salad and a Twix candy bar. But it sure did smell good. 

Losing our sense of smell is one thing; being able to smell like dogs is another matter. Researchers estimate that a dog\'s smell is approximately a hundred thousand to a million times more acute than a human\'s. Bloodhounds have noses ten to one hundred million times more sensitive than humans.

I was amazed to learn that the Silvertip Grizzly bear has a sense of smell seven times stronger than a bloodhound and can detect the scent of food up to 18 miles away. Even fish have a well-developed sense of smell and insects use their antennae for olfaction. 

We can all recall the smells of our childhood. We can also learn about the science of smell. But now that we understand more clearly the importance of smell, we should all be willing to \"wake up and smell the coffee\" and, no matter how busy we may be, we must \"stop to smell the roses.\" 

Think about it.

Dr. Don Meyer is President of 
Valley Forge Christian College, Phoenixville, PA 
Responses can be mailed to president@vfcc.edu