Eating disorder behaviors, such as binge eating, have been discovered to change the brain’s reward response mechanism and food intake control circuitry, which can encourage these behaviors. Understanding how eating disorder behaviors and neurobiology interact might help explain why these illnesses frequently become chronic and may contribute to the development of future therapies. The National Institutes of Health-funded the study, which was published in JAMA Psychiatry.
Eating Disorder Habits Affect The Brain’s Reward Response
This research is noteworthy because it connects biological and behavioral variables that interact to negatively affect eating patterns, according to Janani Prabhakar, Ph.D., of the National Institute of Mental Health, which is part of the National Institutes of Health. It expands their understanding of the underlying biological reasons of behavioral symptom presentation in eating disorders and provides researchers and clinicians with greater information about how, when, and with whom to intervene.
Eating disorders are severe mental diseases that can result in significant consequences, including death. Examples of common eating disorders are Anorexia nervosa, bulimia nervosa, and binge eating disorder. Eating disorders are characterized by a wide range of behaviors, including binge eating, purging, and limiting food intake.
Guido Frank, M.D., of the University of California, San Diego, and colleagues wanted to see how behaviors across the eating disorder spectrum affect reward response in the brain, how changes in reward response alter food intake control circuitry, and if these changes reinforce eating disorder behaviors in this study.
The research consisted of 197 women with eating disorders such as anorexia nervosa, bulimia nervosa, binge-eating disorder, and other specified feeding and eating disorders, as well as 120 individuals without eating disorders and varied body mass indexes (BMIs) linked with eating disorder behaviors.
The researchers studied brain responses during a taste reward challenge using cross-sectional functional brain imaging. During this exercise, individuals were either given or denied an unexpected, prominent sweet stimulation (a taste of a sugar solution). The researchers looked at a brain reward response known as prediction error, which is a dopamine-related signaling mechanism that quantifies the degree of departure from expectation, or how shocked a person was to receive an unexpected stimulus.
A larger prediction error implies that the individual was startled, whereas a smaller prediction error suggests that they were surprised less. They also looked at whether this brain reaction was linked to ventral-striatal-hypothalamic circuitry, which is linked to food intake control.
In the group of women who did not have eating disorders, the researchers discovered no significant relationship between BMI, eating disorder behavior, and brain reward response. Higher BMI and binge-eating habits were related to reduced prediction error response in the group of women with eating disorders.
Furthermore, the direction of ventral striatal-hypothalamic connection in women with eating disorders was the opposite of that in women without eating disorders, with connectivity directed from the ventral striatum to the hypothalamus. This connection was associated with a positive prediction error reaction and a negative sensation of being out of control after eating.
These findings show that eating disorder behaviors and excessive weight loss or gain altered the brain’s dopamine-related reward circuit response in women with eating disorders, changing brain circuitry linked with food intake regulation and potentially reinforcing eating disorder behaviors.
Women with anorexia nervosa, restricted food consumption, and low BMIs, for example, exhibited a significant prediction error response. This reaction might enhance their food intake-control circuitry, allowing these women to ignore hunger signs. Women with binge-eating episodes and higher BMIs, on the other hand, appear to be at a disadvantage.
Ultimately, this research shows that behavioral characteristics, particularly food intake behavior, contribute to the maintenance and development of eating disorders through modifying one’s internal reward response and altering food intake control circuitry.
However, more study is needed to examine therapies that might target and alter behaviors in people with eating disorders to achieve long-term recovery.