The role of sensitivity to reward and impulsivity in food-cue reactivity.

Exposure to the visual and olfactory characteristics of food can elicit a desire to eat and can stimulate food intake. This study sought to determine the extent to which sensitivity to reward and impulsivity are associated with this 'food-cue reactivity' in two motivational states (food deprived and non-food deprived). Female participants (N=120) were exposed to a pizza cue for three minutes whilst food deprived and non-food deprived. Before and after this period, three measures of food-cue reactivity were taken (ratings of desire to eat, craving, and desired portion size of the cued food). Two important findings emerged from the study. Firstly, individuals with higher levels of trait impulsivity experienced greater changes in appetite ratings in both motivational states (food deprived and non-food deprived). They also reported greater changes in desired portion size of a cued food when food deprived. Secondly, individuals with a high sensitivity to reward experienced a greater change in their desired portion of the cued food, but only when non-food deprived. These results indicate that individual differences in food-cue reactivity could be related to variation in sensitivity to stimuli that predict the occurrence of a reward, and to an inability to exercise sufficient self control in the presence of tempting environmental stimuli.