Magnitude-matching: the measurement of taste and smell

• Published in: Chemical senses 1988-03, Vol.13 (1), p.63-87
• Main Authors: Marks, Lawrence E., Stevens, Joseph C., Bartoshuk, Linda M., Gent, Janneane F., Rifkin, Bathsheva, Stone, Veronica K.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Olfactory system and olfaction. Gustatory system and gustation; Vertebrates: nervous system and sense organs
• ISSN: 0379-864X; 1464-3553
• DOI: 10.1093/chemse/13.1.63

In the method of magnitude-matching, subjects try to judge intensities of sensations from two or more modalities on a single, common scale. Using responses to one modality as a standard makes it possible to compare subjects' suprathreshold perceptions on the other, test modality. A series of ten experiments revealed the following: (i) magnitude-matching ‘works’: with both loudness of tones and lightness of grays as standards, tasters versus nontasters of 6-n-prophylthiouracil (PROP) (as defined by a threshold criterion) show much greater responce to suprathreshold PROP and slightly greater response to surcose; (ii) though superior to rating-scale judgements of sensory intensity made without reference to a second modality, magnitude-matching is not, however, flawless: the cross-modality matching relation produced by a set of magnitude-matches depends systematically on the contextual sets of stimulus levels presented for judgement; (iii) with taste as the standard, old versus young subjects showed only a 25% decrement in responce to the odor intensity of butanol when both groups recieved the same physical (concentration) levels, but a >50% decrement in responce when both groups recieved about the same perceptual levels; (iv) magnitude-matches are much the same whether subjets make their judgements on a bounded rating-scale or an open-ended magnitude-estimation scale: and (v) loudness, lightness and odor intensity serve about equally in magnitude-matching with taste intensity.