ABSTRACT

Olfaction is the process by which chemical stimulants are processed into the sensation of smell. In this process, aerosolized chemical stimulants traverse the nose, move into the olfactory cleft, and eventually contact the olfactory sensory neurons. With a sufficient stimulus, the sensory signal of smell is triggered. This is considered a chemosensory process, as the stimulus is a chemical that binds to a receptor. Most of the other human senses use different stimuli. Vision uses light; hearing uses sound waves; and touch uses pressure. All of those sources are not from a chemical stimulus. Using chemicals to stimulate a response is known as chemosensation. Olfaction shares chemosensation with the sense of taste. Smell and taste are strongly linked in this regard. In fact, 90% of taste, or flavor, is actually smell (Hirsch 1992a). Despite the close association, there are significant differences between smell and taste.