Follow This: The art, science, and subjectivity of smell
4.6.22

How is it that we perceive smell? Does everyone experience scent similarly?
On Monday, Science Daily reported on research into the neural activity that translates into our sense of smell. The paper, by Zhen Chen and Krishnan Padmanabhan of the University of Rochester Medical Center, was recently published in Cell Reports.
The Science Daily article highlights Chen and Padmanabhan’s focus on two very different ways that we experience smell:
“These processes suggest the brain has multiple responses to representing a smell. In one strategy, the brain uses a snapshot, like a painting or a photograph, at a given moment to capture the essential features of the odor. In the other strategy, the brain keeps track of the evolving patterns. It is attuned to which cells turn on and off and when—like a symphony.”
Chen and Padmanabhan’s research compliments earlier work by the Monell Chemical Senses Center. According to a 2019 article by Science Daily, Monell’s research, published in Proceedings of the National Academy of Sciences, explored:
“the extensive individual differences in how we sense odors … how small changes in a single olfactory receptor gene … affect how strong and pleasant a person finds an odor.”
“The Monell and Rochester studies reveal the subjective nature of our experience of smell,” said Nikaeta Sadekar, PhD, Senior Scientist at the Research Institute for Fragrance Materials (RIFM). Dr. Sadeker heads RIFM’s Respiratory Toxicology endpoint and leads a research project in collaboration with Monell to study human odor thresholds—how little of something needs to be present for our scent receptors to detect it.
“This research underscores how sensitive we are to smell,” Dr. Sadekar explained. “In other words, when you smell something, the exposure is not necessarily very high. For instance, we know that the exposure to more than 99% of all current fragrance materials across all cosmetics, air care, personal care, and household cleaning products that a person uses falls below the most conservative inhalation Threshold of Toxicological Concern (TTC) of 470 µg/person/day. Therefore, not even the highest users of fragranced products are putting themselves at any appreciable risk of harm. The odor threshold research RIFM is conducting with Monell, like the earlier Monell and Rochester work, will help refine our understanding of the sensitivity of the sense of human smell.”
Read more: If I can smell it, is it safe?