Attentional Focus Dependent Neural Responses to Food: Distinct Patterns of Activation, Deactivation, and Inter-individual Variability

Dominant theories on obesity state that the brain’s reward circuitry responds with increased activity to rewarding food (palatable, high-calorie), yet empirical support is inconsistent. Prior research shows that neural responses to food stimuli are influenced by attentional focus. Focusing on tastiness (hedonic), is associated with stronger neural responses than focusing on the caloric content (health) or the colour of food (neutral), when presented food stimuli are identical. We pooled data from two published fMRI studies to: (1) examine whether palatability (high/low), and caloric content (high/low) of food stimuli affect neural responses – effects that were undetected in the source datasets; as well as (2) detail the robust neural activity responses to different attentional foci (neutral/health/hedonic). Additionally, we assessed: (3) group-level direction of activation (activation profiles); and (4) inter-individual variability in activation profiles for significant group contrasts. Contrary to the dominant theories, palatability did not significantly affect neural responses, and caloric content effects were limited to three regions. The dominant role of attentional focus in shaping food-related neural responses was confirmed. Most clusters showed significantly greater activation for the hedonic condition, though the direction of activation in group-level activation profiles was not uniform across clusters. While most individuals aligned with group-level activation profiles (increased activation or reduced deactivation), we also observe notable divergences in this alignment. Our study challenges assumptions about a generalised increased neural response to palatable and high-calorie foods. We reinforce the role of attentional focus in neural activity and highlight individual variability as a key factor in food-related decision-making.