The brain’s prefrontal cortex is the site for many executive decisions, such as focusing attention, predicting the consequences of an action, controlling impulses, managing emotional reactions, and coordinating complex behaviors. A team at the Icahn School of Medicine at Mount Sinai, New York City, is investigating the role the prefrontal cortex plays in women with BN and severe loss-of-control (LOC) binge-eating. Their goal is to better understand the neural mechanisms that might explain why some individuals cannot stop taking one more bite or sip during binge-eating episodes.
Dr. Barbara A. Berner and her colleagues used a new portable brain imaging technique, functional near-infrared spectroscopy (fNIRS), to measure activity in the prefrontal cortices of 23 women with BN and 23 healthy controls. The measurements were made during two tasks, a go-no-go task requiring inhibition of eating responses and a standard go-no-go task requiring inhibition of button-pressing responses.
Women diagnosed with BN made more errors on both tasks. BN subgroups with the most severe degree of LOC eating (n=12) and those who felt most strongly that they binge ate during the task (n=12) had abnormally reduced bilateral ventromedial prefrontal cortex and right ventrolateral prefrontal cortex activation associated with inhibition of eating responses. Reduced prefrontal cortex activation may directly contribute to more severe eating-specific control deficient in BN. For the first time, according to Dr. Berner, “this method has allowed us to measure what is happening in the brains of people with BN when they are trying to inhibit their eating responses but cannot.” The authors believe their findings point to the areas in the prefrontal cortex that might be useful targets for treatment in LOC binge eating.
