Individual differences in reward drive predict neural responses to images of food

Abstract

A network of interconnected brain regions, including orbitofrontal, ventral striatal, amygdala, and midbrain areas, has been widely implicated in a number of aspects of food reward. However, in humans, sensitivity to reward can vary significantly from one person to the next. Individuals high in this trait experience more frequent and intense food cravings and are more likely to be overweight or develop eating disorders associated with excessive food intake. Using functional magnetic resonance imaging, we report that individual variation in trait reward sensitivity (as measured by the Behavioral Activation Scale) is highly correlated with activation to images of appetizing foods (e.g., chocolate cake, pizza) in a fronto-striatal-amygdala-midbrain network. Our findings demonstrate that there is considerable personality-linked variability in the neural response to food cues in healthy participants and provide important insight into the neurobiological factors underlying vulnerability to certain eating problems (e.g., hyperphagic obesity).

Figure 1.

Orbitofrontal responses to viewing appetizing and disgusting foods. A, Area of left orbitofrontal cortex showing increased group-average activation for appetizing foods relative to nonfood objects. B, Area of right orbitofrontal cortex showing increased group-average activation for disgusting foods relative to nonfood objects. Color bars indicate T values. Activations are thresholded at p < 0.005, uncorrected for visualization.

Figure 2.

Ventral striatum responses to viewing appetizing and disgusting foods. Areas of ventral striatum showing increased group-average activation for appetizing foods relative to bland foods (A) and disgusting foods relative to bland foods (B). Color bars indicate T values. Activations are thresholded at p < 0.005, uncorrected for visualization.

Figure 3.

Significant modulation of neural responses to appetizing foods by trait reward drive. Scatter plots show BOLD signal change in peak activated voxels for appetizing relative to bland foods, plotted as a function of participants' BAS-drive scores. Regression lines and 95% confidence intervals are shown.