Individuals with anorexia nervosa (AN) follow a low-fat, low-calorie diet despite being in a state of emaciation. These maladaptive food choices may involve fronto-limbic circuitry associated with cognitive control, habit, and reward.

Investigators, in this study, determined whether high-frequency repetitive transcranial magnetic stimulation (rTMS) to the left dorsolateral prefrontal cortex (DLPFC) could affect food-related choice behavior in patients with severe, enduring (SE)-AN.

For the purpose of this study, 34 females with SE-AN completed a Food Choice Task before and after 20 sessions of real or sham rTMS treatment and at a 4-month follow-up. Participants had to rate high- and low-fat food items for healthiness and taste and then make a series of choices between a neutral-rated food and high- and low-fat foods. Study outcomes included the proportion of high-fat and self-controlled choices made. A comparison group of 30 healthy women was also included in the study. This group completed the task at baseline.

Baseline data were consistent with previous findings. In comparison with healthy controls, SE-AN individuals preferred low-fat foods and exercised self-control on a greater proportion of trials. There seemed to be no significant effect of rTMS treatment nor time on food choices related to fat content. Among SE-AN individuals given real rTMS, a decline in self-controlled food choices was evident at post-treatment, relative to baseline. There was an increase in the selection of tasty-unhealthy foods.

In patients with SE-AN, rTMS could possibly encourage more flexibility in relation to food choice. This could be attributed to the neuroplastic changes in the DLPFC or in associated brain areas.

Source: Dalton B, Foerde K, Bartholdy S, et al. The effect of repetitive transcranial magnetic stimulation on food choice-related self-control in patients with severe, enduring anorexia nervosa. Int J Eat Disord. 2020 Apr 20.