Testing a learning-based account of interoceptive hunger using an illusory induction

Physiological changes cause many interoceptive cues (e.g., a rumbling stomach), and so it is often assumed they also cause their motivational consequences (e.g., hunger). However, there is grounds to suspect that the meaning of interoceptive cues are learned and it is their meaning that causes their motivational consequences. We tested this possibility by psychologically inducing an illusory interoceptive hunger cue to see if it stimulated hunger and food intake. Participants (n = 130) received either a stomach rumbling or control sound (electrical arcing/buzzing), while judging liking for non-food pictures, and the perceived location of the sound (i.e., computer/unsure/body) - the latter to detect if the illusion occurred. Food was available throughout testing. Participants who heard stomach rumbling and mislocalised this sound to their own stomach (i.e., as if their stomach was rumbling) were both hungrier and consumed around 50% more food relative to: (1) those who did not experience this illusion; and (2) those who heard the control sound. There was no difference among these groups in when they last ate. Susceptibility to the illusion was greatest in those who reported utilising stomach rumbling as an interoceptive hunger cue. These findings suggest that interoceptive cues can cause motivationally salient behaviour via a psychological pathway, one consistent with a learning-based model of hunger (i.e., where cue meaning is learnt and meaning drives behaviour) and with a predictive coding account of interoception (i.e., the generation of brain-based models of bodily events) - models that are related via a dependence on experience.