Systematically lower structural brain connectivity in individuals with elevated food addiction symptoms

Symptoms of food addiction have been observed in both obesity and eating disorders. The food addiction model may therefore posit a continuum of dysfunctional personality traits, including increased impulsivity and poor decision-making. The current study explored the neuroanatomy of addictive-like eating behavior from a novel triadic model of addiction. Specifically, we focused on three interacting neural systems; a sensitized impulsive, reward system associated with striatal structures, a desensitized reflective control system governed by prefrontal cortex, and a disrupted insula-mediated interoceptive system responsible for integrating and translating interoceptive, somatic signals into feelings of anticipation, desires, or cravings. Sixty-four healthy-weight Chinese university students were scanned for high-resolution structural and diffusion imaging. Data from the Yale Food Addiction Scale (YFAS), Binge Eating Scale, Eating Attitude Test-26, UPPS-P Impulsive Behavior Scale, and Delay Discounting Task were collected. Based on YFAS-score, participants were divided into a High Food Addiction group (HFA) and a Low Food Addiction group (LFA). Diffusion tensor imaging results revealed that compared to LFA, HFA had lower structural connectivity between insula and anterior cingulate cortex, insula and caudate, and ventromedial Prefrontal Cortex (vmPFC) and putamen. The Voxel-Based Morphometry analysis suggested marginally lower gray matter volume in the left vmPFC in HFA. Finally, behavioral results, indicated that higher food addiction symptoms were associated with personality traits exhibited in eating disorders including impulsive decision-making. These findings suggest that even in a healthy population, some individuals may be more susceptible to develop unhealthy relationships to food, which at least partially is manifested in lower structural connectivity between brain regions associated with interoceptive awareness, decision-making, and reward.