title: Flavor-intensity perception: effects of stimulus context.
abstract: Stimulus context affects judgments of intensity of both gustatory and olfactory flavors, and the contextual effects are modality-specific. Does context also exert separate effects on the gustatory and olfactory components of flavor mixtures? To answer this question, in each of 4 experiments, subjects rated the perceived intensity of 16 mixtures constructed by combining 4 concentrations of the gustatory flavorant sucrose with 4 concentrations of the retronasal olfactory flavorant citral. In 1 contextual condition of each experiment, concentrations of sucrose were relatively high and those of citral low; in the other condition, the relative concentrations of sucrose and citral reversed. There were 2 main results: First, consistent with earlier findings, in 5 of the 8 conditions, the ratings were consistent with linear addition of perceived sucrose and citral; departures from additivity appeared, however, in 3 conditions where the relative concentrations of citral were high. Second, changes in context produced contrast (adaptation-like changes) in perceived intensity: The contribution to perceived intensity of a given concentration of a flavorant was smaller when the contextual concentrations of that flavorant were high rather than low. A notable exception was the absence of contextual effects on the perceived intensity of near-threshold citral. These findings suggest that the contextual effects may arise separately in the gustatory and olfactory channels, prior to the integration of perceived flavor intensity.
authors.affiliation: John B. Pierce Laboratory, 290 Congress Avenue, New Haven, CT 06519, USA. marks@jbpierce.org
authors.forename: Lawrence E
authors.initials: LE
authors.lastname: Marks
authors.forename: Timothy G
authors.initials: TG
authors.lastname: Shepard
authors.forename: Kelly
authors.initials: K
authors.lastname: Burger
authors.forename: Emily M
authors.initials: EM
authors.lastname: Chakwin
mesh_terms: D000080462:Acyclic Monoterpenes; D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D004305:Dose-Response Relationship, Drug; D005260:Female; D005421:Flavoring Agents / Q000494:pharmacology*; D006801:Humans; D007600:Judgment / Q000187:drug effects / Q000502:physiology; D008297:Male; D039821:Monoterpenes / Q000008:administration & dosage; D055696:Olfactory Perception / Q000187:drug effects* / Q000502:physiology; D011601:Psychophysics; D012903:Smell / Q000187:drug effects* / Q000502:physiology; D013395:Sucrose / Q000008:administration & dosage; D013549:Sweetening Agents / Q000008:administration & dosage; D055815:Young Adult
chemical_list: D000080462:Acyclic Monoterpenes; D005421:Flavoring Agents; D039821:Monoterpenes; D013549:Sweetening Agents; D013395:Sucrose; C007076:citral