Food reward
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POSITIVE
Food reward was measured using the LFPQ-J, a computer-based task that assesses the different components of food preference and reward.The LFPQ-J consists of two tasks: single- and paired-food tasks. Food reward was evaluated using the following four parameters: explicit liking, explicit wanting, implicit wanting, and relative preference. In the single-food task, participants were asked to rate the extent to which they thought they were liking or wanting each randomly presented food item on a 100-mm visual analogue scale to measure explicit liking and wanting. Briefly, single-food images were randomly shown to the participant, and participants responded according to the following two questions: ‘How pleasant would it be to taste some of this food now?’ (explicit liking) and ‘How much do you want some of this food now?’ (explicit wanting), anchored at each end with ‘not at all’ and ‘extremely’. In the paired-food trials, each food image was presented in turn with a food image from the other category, and participants were instructed to select the food they ‘most want to eat now’ as quickly as possible. Implicit wanting was measured using the reaction time of the test and selected categories, and relative preference was measured using the number of selections per category.For the parameters measured in all food-reward measurements, the fat appeal bias for foods with different fat contents and the taste appeal bias for foods with different tastes were evaluated. Bias scores for fat content and taste were computed by subtracting the mean low fat scores from the mean high fat scores and the mean savoury scores from the mean sweet scores. Positive values indicate a preference for high fat and/or sweet foods; negative values indicate a preference for low fat and/or savoury foods; and a score of 0 indicates an equal preference between fat content and taste categories.