ABSTRACT
Colloquially referred to as "taste," flavor is in reality a thoroughly multisensory experience. Yet, a mechanistic understanding of the multisensory computations underlying flavor perception and food choice is lacking. Here, we used a multisensory flavor choice task in rats to test specific predictions of the statistically optimal integration framework, which has previously yielded much insight into cue integration in other multisensory systems. Our results confirm three key predictions of this framework in the unique context of flavor choice behavior, providing novel mechanistic insight into multisensory flavor processing.NEW & NOTEWORTHY The authors demonstrate that rats make choices about which flavor solution (i.e., taste-odor mixture) to consume by weighting the individual taste and odor components according to the reliability of the information they provide about which solution is the preferred one. A similar weighting operation underlies multisensory cue combination in other domains and offers novel insight into the computations underlying multisensory flavor perception and food choice behavior.
Subject(s)
Adaptation, Physiological/physiology , Behavior, Animal/physiology , Choice Behavior/physiology , Food Preferences/physiology , Olfactory Perception/physiology , Taste Perception/physiology , Animals , Cues , Female , Likelihood Functions , Male , Rats , Rats, Long-EvansABSTRACT
The mechanisms by which taste and odor are combined in determining food choice behavior are poorly understood. Previous work in human subjects has yielded mixed results, potentially due to differences in task context across studies, and a lack of control over flavor experience. Here, we used rats as a model system to systematically investigate the role of experience and unisensory component liking in the multisensory interactions underlying consumption behavior. We demonstrate that taste-smell mixture consumption is best explained by a linear average of component liking. The observed pattern of results was not dependent on prior experience with specific taste-smell combinations, and unique for multisensory as opposed to unisensory mixture consumption. The results are discussed with respect to existing models of flavor integration, and a maximum-likelihood integration model previously described for multisensory judgments in other systems.
