Different brain regions support deliberation during food choice in disordered and healthy eating

The brain is wired to drive behavior towards foods that are high in sugar and fat. This natural pattern is reversed in individuals with anorexia nervosa (AN), who prefer low-sugar and low-fat foods to the point of starvation and even death. Here, we aimed to understand how changes in the brain contribute to the pattern of maladaptive food-related decisions in AN. We combined decision-making tasks with computational modeling of behavior and fMRI to examine food and non food-related decisions in individuals with AN and healthy controls (HC). Results from this pre-registered study suggest that patients with AN employ a decision process that relies on sampling and evaluating evidence that is similar to that in healthy individuals, regardless of the type of decision. However, when deliberating about what to eat, while HC engage the hippocampus, individuals with AN engage the striatum in addition to the hippocampus, apparently as sources of evidence in the decision process. These findings suggest that the maladaptive reversal of preferences in AN is related to reliance on different inputs to the process that leads to choice of food, rather than a maladaptive decision process per se.