The relation between craving and binge eating: Integrating neuroimaging and ecological momentary assessment.

The role of craving in binge eating characteristic of bulimia nervosa (BN) is inconclusive. A network of regions associated with cue reactivity to food and substances has been identified, comprised of the amygdala, orbitofrontal cortex, insula, and striatum. The goal of this study was to examine individual differences in BOLD response in this appetitive network as moderators of the relationship between craving and binging in the natural environment in women with BN. Women with BN (N = 16) completed a baseline measure of craving and a fMRI scan, where they viewed neutral cues and food cues. After each run, craving for food was assessed. Participants then completed an ecological momentary assessment six times a day via smart phone and recorded binge eating and craving. Participants exhibited significantly increased BOLD response in the left amygdala in response to food cues compared to neutral cues. However, individual differences in BOLD response were not correlated with self-report craving throughout the scan. The relationship between craving and binging in everyday life was moderated by individual differences in activation in the caudate, insula, and amygdala. Women with greater activation in these regions demonstrated significant increases in craving prior to binge eating. Those who did not exhibit increases in activation did not exhibit increases in craving prior to binge eating in the natural environment. Craving may not underlie binge eating for all individuals with BN. However, these results indicate that neural response to food cues may affect individual differences in the daily experience of craving and binge eating.