Craving is thought to be a specific
desire state that biases choice toward the desired object, be it
chocolate or drugs. A vast majority of people report having experienced
craving of some kind. In its pathological form craving contributes to
health outcomes in addiction and obesity. Yet despite its ubiquity and
clinical relevance we still lack a basic neurocomputational
understanding of craving. Here, using an instantaneous measure of
subjective valuation and selective cue exposure, we identify a
behavioral signature of a food craving-like state and advance a
computational framework for understanding how this state might
transform valuation to bias choice. We find desire induced by exposure
to a specific high-calorie, high-fat/sugar snack good is expressed in
subjects’ momentary willingness to pay for this good. This effect is
selective but not exclusive to the exposed good; rather, we find it
generalizes to nonexposed goods in proportion to their subjective
attribute similarity to the exposed ones. A second manipulation of
reward size (number of snack units available for purchase) further
suggested that a multiplicative gain mechanism supports the
transformation of valuation during laboratory craving. These findings
help explain how real-world food craving can result in behaviors
inconsistent with preferences expressed in the absence of craving and
open a path for the computational modeling of craving-like phenomena
using a simple and repeatable experimental tool for assessing
subjective states in economic terms.
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