How Human Olfaction Is Made Possible Essay

1243 Words Nov 8th, 2014 null Page
From an evolutionary standpoint, olfaction is one of the oldest senses. Aiding in our memory and also in the detection of hazards, the sense of smell became a necessity in the human struggle for survival. From the creation of synthetic fragrances to even the enhancing of our sense of taste, olfaction has even affected our culture. Our sense of smell has helped establish the human race into what it is today, but could it also be affecting us on a subconscious level?

First we must understand how human olfaction is made possible. Our sense of smell is part of our chemosensory system; senses in our body that rely on chemical molecules. Air (a mixture of molecules) enters the nose through the nostrils and is filtered before coming in contact with the Olfactory Epithelium. The Olfactory Epithelium is a layer of olfactory receptor cells. When molecules bind to the olfactory receptor, they create signals that fire and travel through the olfactory tract straight to different areas in the brain; such as the amygdala, thalamus and the neocortex. Once they’ve reached these areas in the brain they relay information that can trigger memories or even our “fight or flight” response.

The definition of a pheromone is, “substances which are secreted to the outside by an individual and received by a second individual” (Verhaeghe et al, 2013). These chemicals, as other odors, travel through the olfactory tract and to the brain; but don’t trigger the exact same responses as other scents.…

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