Brain scans reveal how sweet and sour soundtracks shape taste processing, with sweet music making simple taste solutions feel more pleasant.
Study: Music–taste interactions enhance gustatory and sensorimotor brain activity. Image Credit: LightField Studios / Shutterstock
In a recent study published in the journal Scientific Reports, researchers evaluated the effects of music on the brain’s encoding of taste.
Eating and reproduction are essential for survival. The sensory system supports these fundamental behaviors by identifying, assessing, and predicting external stimuli. The brain integrates input from different sensory modalities, optimizing information processing. While the effects of smell and vision on taste perception are well studied, research increasingly suggests that hearing can influence taste experiences.
For instance, amplifying the chewing sounds of apples and potato crisps increases crispiness perception. Studies also indicate that certain acoustic features evoke specific taste qualities. For example, low-pitched percussive and dissonant sounds are often associated with bitterness or sourness, while high-pitched consonant and legato sounds are linked to sweetness. Nevertheless, how music changes taste perception remains unclear.
About the study
In the present study, researchers explored the neural underpinnings of music-taste interactions. They recruited healthy participants aged 18–55 years, with normal senses of hearing, taste, vision, and smell.
The study involved neuroimaging and behavioral sessions. In the first session, participants underwent three functional magnetic resonance imaging (fMRI) scans. Participants were presented with multisensory interaction, gustatory, and auditory tasks inside the scanner.
The multisensory interaction task involved four conditions: sweet music plus sweet taste, sweet music plus sour taste, sour music plus sweet taste, and sour music plus sour taste. These conditions were randomly presented eight times.
In the gustatory task, participants were presented with only two conditions: sour and sweet tastants, with each repeated eight times. The auditory task also included two conditions, sour and sweet soundtracks, each repeated eight times.
The sweet and sour tastants were sucrose and citric acid, respectively. The sour soundtrack featured sharper, higher-pitched attacks and mild dissonance, whereas the sweet soundtrack featured legato articulation and consonant harmony.
Following fMRI scanning, participants underwent behavioral sensory evaluation, in which the same sound stimuli and an extended set of taste stimuli (sucrose, citric acid, and their mixtures) were assessed.
The behavioral session comprised 15 tasting trials across three sound conditions (silence, sweet music, and sour music) and five tastants. Participants rated sweetness intensity, sourness intensity, tastant pleasantness, and sound-taste congruency.
After the trials, subjects listened to two soundtracks and rated the pleasantness of each soundtrack and the extent to which each was associated with each taste.
Findings
The study recruited 48 healthy, right-handed individuals, including 27 females, with a mean age of 27.5 years. fMRI data were acquired from only 28 participants due to technical issues, while behavioral data were available for all subjects; the main behavioral results were reported for the 28 participants with complete neuroimaging and behavioral data. Sound-taste congruency ratings showed that purely sour and sweet tastants were more congruent with the sour and sweet soundtracks, respectively.
Notably, congruency ratings matched the ratios of citric acid and sucrose in mixture tastants. The 75% sucrose plus 25% citric acid solution was more congruent with sweet music, while the 25% sucrose plus 75% citric acid solution was more congruent with sour music. Notably, the 50% sucrose plus 50% citric acid solution had equal congruence with both soundtracks.
Voxel-wise conjunction analyses revealed no significant shared activation between the sweet-taste and sweet-music conditions. However, both conditions independently engaged similar anatomical regions: bilateral postcentral gyri, left ventromedial prefrontal cortex, left gyrus rectus, and right precentral gyrus. Rolandic operculum activation was also noted in both conditions, but in different hemispheres.
Further, voxel-wise conjunction analysis revealed a small but significant shared activation cluster between sour taste and sour music in the right postcentral gyrus. Descriptive anatomical overlap was also observed in the left gyrus rectus, right supramarginal gyrus, and ventromedial prefrontal cortex.
Combining music and taste led to greater activation than taste alone. For the sweet music plus sweet taste condition, cluster peak activations were noted in the left precuneus, right precentral gyrus, and left postcentral gyrus.
For the sour music plus sour taste condition, cluster peak activations were detected in the left lingual gyrus, right postcentral gyrus, left cerebellar lobule VI, left precentral gyrus, and right calcarine fissure and surrounding cortex.
Pairing sweet taste with sweet music led to greater activation in the rolandic operculum and superior temporal gyri than pairing it with sour music. However, the equivalent comparison for sour taste paired with sour versus sweet music did not identify significant clusters, suggesting that congruency-specific effects were limited.
Behavioral results from the 28-participant neuroimaging subset indicate a significant main effect of sound condition on pleasantness ratings; tastant solutions were significantly more pleasant with sweet music than in silence. Further, 100% citric acid was the least pleasant.
Regarding sweetness and sourness, there was a significant main effect of tastant type: higher percentages of sucrose or citric acid in the solution increased sweetness or sourness ratings, respectively. However, sound condition did not significantly alter sweetness or sourness intensity ratings in this subset, indicating that music effects on taste intensity were modest.
Conclusions
In summary, sweet and sour soundtracks engaged taste-processing regions in the brain, and concurrent gustatory-auditory stimuli enhanced neural responses compared to taste alone. Listening to sweet music increased the pleasantness of the tastant.
Overall, neural enhancement appeared to be driven mainly by simultaneous multi-modal input, with additional modulation under specific congruent pairings. These results provide novel insights into the neural underpinnings of sound-taste interactions, contributing to the understanding of how auditory cues influence taste-related processing and pleasantness through multisensory integration.
However, the authors note that the fMRI sample was small and homogeneous, behavioral effects were modest, and co-activation in overlapping regions does not necessarily prove shared neural coding.
Future studies with larger and more diverse samples, counterbalanced task order, and more complex food stimuli are needed.
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