18: The Dog Beneath the Skin

Name: Stephen D, age 22,

Occupation: Medical student

Diagnosis: Hypermosmia

Patient is a user of cocaine, and PCP to get high. He dreamt he was a dog and then awoke to be living out his dream. He described all this elevated sense of smell as transformative—he could ‘see’ objects like never before and distinguish between multiple shades of brown leather bound books. He was able to identify his patients before he saw them and navigate the city of New York using his sense of smell alone.

Suddenly after 3 weeks of super human sense of smell, he returned to normal—content to have had the experience, and reminiscent of those days.

Enhancement of smell: can have multiple sources such as paraphilia and fetishism; overexcitement as in the case of drug-use.

Hyperosmia is characterized as a heightened sense of smell, which is usually due to a lower threshold for smell.

This case of a patient with an elevated sense of smell is pertinent to lecture content because we have discussed which structures of the brain’s anatomy are responsible for our perception of smell. The limbic system is a brain structure that includes the olfactory bulbs and controls emotions. Consequently, the sense of smell is the sense most closely associated with memory and emotion.

In addition, our senses are translated into electrochemical signals our brains can perceive based on external stimuli. The olfactory particles enter the nasal cavity and bind to receptors, which in turn trigger a response in the brain. Action potentials are essential for translating and transporting information from the external environment. Once sufficient amount of action potentials are summated to reach threshold, a response is elicited.