Bringing us Back to our Senses

Imagine finally taking time to smell the roses, and there was no scent. Same with the fresh cut grass of a golf course, your favorite perfume, a filet mignon grilled to perfection, the lavender shampoo in a newborn’s hair. Nothing. Well, you would likely be one of the 6.3 million Americans experiencing anosmia, or a total loss of smell.

Every whiff we take sets off a remarkable chain of events. Our brains first detect and categorize smells thanks to the central nervous system, which transmits electrical impulses to olfactory receptors in the nasal cavity. This information makes its way to the olfactory bulb at the bottom of the forebrain to higher functioning regions of the brain.

Without the ability to smell, our sense of taste suffers, and many develop emotional side-effects such as issues with self-confidence and depression. Few understand the complexities of anosmia better than Richard Costanzo, Ph.D., of VCU’s Smell and Taste Disorders Center, and Daniel Coelho, M.D., associate professor of head and neck surgery in the Department of Otolaryngology and medical director of the VCU Cochlear Implant Center.

Funded by the entrepreneur Scott Moorehead who lost his sense of smell, the pair looked to the same principal for electrophysiology technology in hearing implants: an external sensor and internal processors. Only theirs spark select parts of the brain not getting smell transmissions due to injury or disease. Small gas sensors detect odor molecules and send data to a microprocessor that taps electrical signals to stimulate the olfactory bulb. The result, a smell sensation.

“We would program the sensor input and microprocessor to know this odor is a banana and this one is a rose,” Costanzo said. “Then we match up the sensor input with a stimulation pattern for the olfactory bulb. So, if a patient goes into a room and there’s a banana smell, a specific odor pattern is activated in the bulb. Now, instead of eating mush they are now getting the banana sensation. ”Richard M. Costanzo. Ph.D. Professor Emeritus Department of Physiology and Biophysics and Department of Otolaryngology Head and Neck Surgery School of Medicine