Adaptive weighting of taste and odor cues during flavor choice

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.

The tongue map and the spatial modulation of taste perception

“…While different researchers have come to different conclusions to this question (e.g., see the quote from Munger in Hammond, 2017 , mentioned earlier), it might anyway be argued that threshold measures are actually of rather less relevance than any spatial differences in people's responses to suprathreshold taste stimuli (see Feeney and Hayes, 2014 ; Hyde and Witherly, 1993 ). Ultimately, one of the important points to stress here is that taste localization, just like other aspects of flavour perception, is a fundamentally multisensory phenomenon ( Maier and Elliott, 2020 ; Simon et al, 2006 ; Spence et al, 2015 ).…”

Exploring the Links between Colours and Tastes/Flavours

“…), influences various aspects of taste/flavour perception is critically evaluated. We discuss various approaches to conceptualizing colour's influence over taste/flavour, including Ecological Valence Theory [86], Colour-in-Context Theory [34], the increasingly-popular Bayesian Decision Theory (see [59,70]), and suggest a network modelling approach as a potential future computational direction for the field. We briefly summarize the limited evidence concerning the neural underpinnings of colour-flavour interaction, highlight a number of the problems that are associated with trying to model colour's influence over taste/flavour perception, and offer guidance for future research.…”

“…However, Marks and colleagues have argued that, in the case of olfaction and gustation, the noise is pooled across the flavour senses [72].) Recent work [70] has demonstrated that this approach to modelling the combination of olfactory and gustatory cues can be successfully used to predict flavour choice (i.e., preference) in rats. In humans, meanwhile, those combinations of olfactory and gustatory cues that commonly co-occur in the foods that we consume have been shown to exhibit enhanced integration, including increased 'oral referral' [66,67] (see also [140], for a review), as well as a greater crossmodal, or multisensory enhancement of smell by taste [17,27].…”

“…As such, if one were to try to model the integration of the colour expectations with gustatory information, one would first need to establish the appropriate association/dimensions a priori. Maier and Elliott [70] took an interesting approach by using flavour choice as their behavioural response measure; preferences may be one way to ''standardise'' across the senses. However, their study was conducted with rats and relied upon conditioning a relationship between a specific odour and caloric density.…”

Cortical Hub for Flavor Sensation in Rodents

“…Largely, this sensory information is transmitted centrally along separate pathways, but the integration of these three intraoral senses into a unitary object generates the perception of flavor (Small, 2012 ). As a consequence, the intraoral sensations associated with eating are inherently related (Schul et al, 1996 ; Sakai and Yamamoto, 2001 ; Sakai and Imada, 2003 ; Torregrossa et al, 2012 ; Blankenship et al, 2019 ; Fredericksen et al, 2019 ; Elliott and Maier, 2020 ; Maier and Elliott, 2020 ; McQueen et al, 2020 ). Our current understanding of the behavioral and neural relationships between the intraoral senses is due in large part to many notable human studies (Arabie and Moskowitz, 1971 ; Moskowitz, 1973 ; Bartoshuk et al, 1982 ; Frank et al, 1993 ; Stevenson et al, 1995 ; Dalton et al, 2000 ; Hollowood et al, 2002 ; De Araujo et al, 2003 ; de Araujo et al, 2013 ; Prescott et al, 2004 ; Small et al, 2004 , 2008 ; Veldhuizen et al, 2010 ; Lim and Johnson, 2011 ; Veldhuizen and Small, 2011 ; Green et al, 2012 ).…”