Gustatory stimulation influences the processing of intranasal stimuli.

OBJECTIVES

Taste and smell interact. The aim of this study was to examine this interaction using gustatory and olfactory stimuli applied at the same time, which exhibited perceptual compatibility and incompatibility.

METHODS

Thirty-two, young, healthy normosmic subjects (16 men, 16 women) took part in two randomized sessions. Event-related potentials (ERP) were recorded in response to vanillin, or gaseous CO2. These two conditions were combined with three "taste conditions" including sweet taste, sour taste, and the intraoral presentation of an empty taste dispenser.

RESULTS

Vanillin responses were largest for the "sweet" condition, while they were smaller for the "sour condition". In contrast, responses to CO2 were largest under the "sour" condition, and smallest under the "sweet" condition. Moreover, during the "sweet" condition the latencies of P1 and N1 were shorter than in the "sour" condition, which was the other way around for CO2.

CONCLUSIONS

Results of the present investigation suggested that (1) the early processing of intranasal chemosensory stimuli is modulated through concomitant gustatory stimulation, and that (2) this modulation may depend, at least in part, on the contextual compatibility between intranasal and intraoral stimuli.