How is smell perception measured?

The measurement of smell perception has seen significant advancements, particularly in the context of digitizing smell. Dr. Noam Sobel discusses the development of a set of rules that link odor structure to odor perception. This effort aims to predict odor characteristics based on molecular structure, similar to how color perception is linked to light wavelength. This has been a challenging area, but recent research has made progress in establishing these connections 1.

Additionally, Dr. Sobel mentions the use of standardized clinical tests for olfaction, such as the University of Pennsylvania Smell Identification Test (UPSIT). This test involves scratch-and-sniff mechanisms that present 40 different odors to assess smell perception. Another method mentioned is the European counterpart known as "sniffing sticks". These traditional tests have been used extensively to evaluate olfactory function in conditions like Alzheimer’s and Parkinson’s disease 2.