Pavlovian-instrumental transfer effects in individuals with binge eating

The food addiction model of binge-eating postulates that hyperpalatable food can sensitize the reward processing system and lead to elevated cue-elicited motivational biases towards food, which eventually become habitual and compulsive. However, previous research on food reward conditioning in individuals with binge-eating is scarce. The present study examined the Pavlovian-instrumental transfer (PIT) effects in individuals with recurrent binge-eating. It was hypothesized that hyperpalatable food would elicit specific transfer effects, i.e., biased responding for the signaled food even after satiation on that food, and this effect would be stronger in individuals with binge-eating compared to healthy controls.

Fifty-one adults with recurrent binge-eating and 50 weight-matched healthy controls (mean age: 23.95 [SD = 5.62]; % female = 76.2%) completed the PIT paradigm with food rewards. Participants also completed measures of hunger, mood, impulsivity, response disinhibition, and working memory. Mixed ANOVAs were conducted to examine transfer effects and if they differed between individuals with binge-eating and those without.

The group by cue interaction effect was not significant, suggesting that the specific transfer effect did not differ between groups. The main effect of cue was significant, indicating that the outcome-specific cue biased instrumental responding towards the signaled hyperpalatable food. However, the biased instrumental responding was attributable to suppressed responding in the presence of the cue predicting no reward, rather than enhanced responding in the presence of the specific food-predicting cues.

The present findings did not support the hypothesis that individuals with binge-eating would be more vulnerable to specific transfer effects elicited by hyperpalatable food, as measured by the PIT paradigm.