From attributes to value: neural correlates of a front-of-package label on food decision-making – an fMRI study

Diet-related chronic diseases remain a major public health concern worldwide, motivating policymakers to implement behavioral interventions such as front-of-package labels (FoPLs) to encourage healthier food choices. Although FoPLs like the Nutri-Score are increasingly used to communicate nutritional quality in a simple way, little is known about how they shape specific attributes of food perception and choice, and how these effects manifest in the brain. This dissertation bridges behavioral economics and cognitive neuroscience to examine how a simplified color-coded frame, modeled on the Nutri-Score system, influences food-related decisions. Using a multi-method design, the project first established robust theoretical and methodological foundations through targeted pilot experiments. These confirmed that the chosen valuation paradigm and the operationalization of the color-coded frame reliably affect willingness-to-pay (WTP), perceived healthiness, and tastiness. In the main fMRI experiment, forty healthy participants (28 females, age: M = 23.8 years, SD = 3.1 years) rated food products under control and treatment conditions while brain activity was recorded. Results showed that the color-coded frame systematically decreased WTP and tastiness ratings for less healthy items and aligned healthiness perceptions with the nutritional information implied by the frame. Neural data revealed distinct patterns of activity within valuation-related areas (e.g., ventromedial prefrontal cortex, anterior prefrontal cortex), regions linked to self-regulation and goal-directed behavior (e.g., dorsolateral prefrontal cortex, inferior frontal gyrus), and the thalamus, highlighting the interplay of reward processing, cognitive control, and homeostatic integration. Additional analyses examined how nutritional composition interacted with the label’s effect and explored whether FoPLs alter the supra-additive reward response to high-fat, high-carbohydrate foods. Finally, out-of-sample forecasting demonstrated that neural measures, particularly signals in the nucleus accumbens and medial prefrontal cortex, could predict binary choices for new products, underlining the added value of neural data beyond self-reports. Taken together, these findings show that FoPLs can shift food choices by engaging affective and deliberative pathways, supporting a goal-directed decision-making process. This work offers new insights into the conditions under which labeling can alter habitual patterns and provides a neurobehavioral basis for designing nudges that promote sustained healthy eating.