A salty-congruent odor enhances saltiness: functional magnetic resonance imaging study.
Excessive intake of dietary salt (sodium chloride) may increase the risk of chronic diseases. Accordingly, various strategies to reduce salt intake have been conducted. This study aimed to investigate whether a salty-congruent odor can enhance saltiness on the basis of psychophysical (Experiment 1) and neuroanatomical levels (Experiment 2). In Experiment 1, after receiving one of six stimulus conditions: three odor conditions (odorless air, congruent, or incongruent odor) by two concentrations (low or high) of either salty or sweet taste solution, participants were asked to rate taste intensity and pleasantness. In Experiment 2, participants received the same stimuli during the functional magnetic resonance imaging scan. In Experiment 1, compared with an incongruent odor and/or odorless air, a congruent odor enhanced not only taste intensity but also either pleasantness of sweetness or unpleasantness of saltiness. In Experiment 2, a salty-congruent combination of odor and taste produced significantly higher neuronal activations in brain regions associated with odor-taste integration (e.g., insula, frontal operculum, anterior cingulate cortex, and orbitofrontal cortex) than an incongruent combination and/or odorless air with taste solution. In addition, the congruent odor-induced saltiness enhancement was more pronounced in the low-concentrated tastant than in the high-concentrated one. In conclusion, this study demonstrates the congruent odor-induced saltiness enhancement on the basis of psychophysical and neuroanatomical results. These findings support an alternative strategy to reduce excessive salt intake by adding salty-congruent aroma to sodium reduced food. However, there are open questions regarding the salty-congruent odor-induced taste unpleasantness.
Smell & Taste Clinic, Department of Otorhinolaryngology, University of Dresden Medical School, Dresden, Germany.
Han-Seok
HS
Seo
Emilia
E
Iannilli
Cornelia
C
Hummel
Yoshiro
Y
Okazaki
Dorothee
D
Buschhüter
Johannes
J
Gerber
Gerhard E
GE
Krammer
Bernhard
B
van Lengerich
Thomas
T
Hummel
D000328:Adult; D001921:Brain / Q000502:physiology; D001931:Brain Mapping / Q000379:methods; D004039:Diet, Sodium-Restricted; D019422:Dietary Sucrose / Q000008:administration & dosage; D005260:Female; D019649:Food Industry / Q000379:methods; D005518:Food Preferences / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009812:Odorants; D055696:Olfactory Perception / Q000502:physiology*; D012903:Smell / Q000502:physiology; D017673:Sodium Chloride, Dietary / Q000008:administration & dosage*; D013649:Taste / Q000502:physiology; D055697:Taste Perception / Q000502:physiology*; D055815:Young Adult
D019422:Dietary Sucrose; D017673:Sodium Chloride, Dietary