Does the Nose Know?


By Lisa Qu

Smelling a cup of freshly brewed coffee can be a rich, almost magical, experience. In fact, in that brief moment, you are smelling a mixture of more than 800 different molecules that make up the smell of coffee.

Part of what makes that experience so rich also makes the sense of smell notoriously difficult to study. Unlike vision or hearing, where stimuli range along a set scale – for example, brightness or frequency – odorants exist in a multi-dimensional space with most, like coffee, composed of hundreds or even thousands of different compounds in varying combinations. Furthermore, odors can be very transient, perhaps lasting only a short time before being dispersed by a gust of wind.

We also habituate very quickly to odors. For instance, when you first enter a coffee shop, you might smell a very intense coffee aroma, but after just a few minutes, you don’t even notice it. After prolonged exposure, olfactory regions decrease responding so that you no longer actively perceive odor information. Because of this, odors can become difficult to detect after only a short time.

Only recently have we begun to study smell in humans the way we have studied vision or our other senses. But given the ever-growing scientific discovery about smell’s ability to guide behavior, we might be using our nose more than we think.

Why is smell important?

Throughout history, the human nose has been a subject of vanity, medicine, and philosophy. From the inspiration and expiration of oxygen (or life itself), the nose has found its role as the facilitator of our sense of smell. Socrates even defended his purportedly unshapely nose by noting that “my nose is more beautiful because my nostrils flare out and so I can therefore gather in more smells.” Unfortunately, —> Read More