We asked participants to fast before coming in to our lab to complete an experiment in which they viewed pictures of household and food items each paired with a positive, negative or neutral sound. When they arrived to our lab, we randomly assigned half of the participants to eat a sandwich before doing the rest of the study. These recently fed participants showed the typical pattern of greater pupil dilation responses when hearing emotional sounds than when hearing neutral sounds. In contrast, the other participants who were still fasting showed high pupil dilation responses when hearing both emotional and neutral sounds. The hungry participants also had better memory for the food images they were shown than did the sated participants.
