MILWAUKEE: Each of us has, in our nose, about six million smell receptors of around four hundred different types. The distribution of these receptors varies from person to person – so much so that each person’s sense of smell may be unique.
The implications of this study reach beyond the sense of smell alone, and range from olfactory fingerprint-based early diagnosis of degenerative brain disorders to a non-invasive test for matching donor organs.
The method is based on how similar or different two odors are from one another. In the first stage of the experiment, volunteers were asked to rate 28 different smells according to 54 different descriptive words, for example, “lemony,” or “masculine.” The experiment developed a complex, multidimensional mathematical formula for determining, based on the subjects’ ratings, how similar any two odors are to one another in the human sense of smell.
The strength of this formula is that it does not require the subjects to agree on the use and applicability of any given verbal descriptor. Thus, the fingerprint is odor dependent but descriptor and language independent.