Latency and accuracy of discriminations of odor quality between binary mixtures and their components.
Subjects made timed, same-different discriminations of odor quality, with the following principal findings: (i) latency reflected accuracy, with difficult discriminations, i.e. those between 50-50 mixtures and their components, requiring more time than less difficult discriminations, i.e. those between unmixed chemicals. This finding demonstrated the face validity of latency as a measure of qualitative similarity. (ii) Latency provided better resolution among pairs of odors than did errors of discrimination. This finding demonstrated the utility of collecting response times. (iii) Latency-based similarities among odors tested previously predicted similarities among pairs not yet tested. This finding demonstrated internal/predictive validity. (iv) A signal detection model assuming a differencing strategy best described the pattern of errors. Subjects appeared to make relative judgements regarding quality. (v) Finally, latency-based similarities between mixtures and their components demonstrated additivity. This finding suggested that binary mixtures fall on straight lines connecting their components in 'odor-space'.
Wise
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Chemosensory Perception Laboratory, Department of Surgery (Otolaryngology), University of California, San Diego, La Jolla, CA 92093-0957, USA. pwise@ucsd.edu
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D000328:Adult; D004193:Discrimination Learning; D005260:Female; D006801:Humans; D009812:Odorants; D011930:Reaction Time; D012684:Sensory Thresholds; D012903:Smell / Q000502:physiology*