Humans Can Discriminate More than 1 Trillion Olfactory Stimuli

2014/03/20 by Caroline Bushdid, Marcelo O. Magnasco, Leslie B. Vosshall +1 · 2 citations
Neuroscience · Engineering · #Olfactory and Sensory Function Studies #Neurobiology and Insect Physiology Research #Advanced Chemical Sensor Technologies

paper · doi:10.1126/science.1249168

openalex publication_date 2014/03/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

Humans can discriminate several million different colors and almost half a million different tones, but the number of discriminable olfactory stimuli remains unknown. The lay and scientific literature typically claims that humans can discriminate 10,000 odors, but this number has never been empirically validated. We determined the resolution of the human sense of smell by testing the capacity of humans to discriminate odor mixtures with varying numbers of shared components. On the basis of the results of psychophysical testing, we calculated that humans can discriminate at least 1 trillion olfactory stimuli. This is far more than previous estimates of distinguishable olfactory stimuli. It demonstrates that the human olfactory system, with its hundreds of different olfactory receptors, far outperforms the other senses in the number of physically different stimuli it can discriminate.

Cited by

• Leslie B. Vosshall [wikipedia]
• Odor [wikipedia]

Related

• Humans can discriminate trillions of olfactory stimuli, or more, or fewer
• Odors as cognitive constructs: history of odor classification and attempts to map odor percepts to physical and chemical parameters
• The perception of odor pleasantness is shared across cultures
• Science is perception: what can our sense of smell tell us about ourselves and the world around us?
• Constructing an olfactory perceptual space and predicting percepts from molecular structure