Neurofeedback intervention based on functional near-infrared spectroscopy compared with sham control to improve inhibitory cognitive control in patients with severe obesity and food addiction: The protocol of a monocentric prospective randomized parallel-group single-blind interventional study.

BACKGROUND & AIMS: Overconsumption of hyperpalatable foods and obesity are associated with reduced activity of brain regions involved in executive functions, including the dorsolateral prefrontal cortex (dlPFC). Neurofeedback (NF) based on functional near-infrared spectroscopy (fNIRS) appears as an easily feasible neuromodulation method to assist voluntary improvement of inhibitory cognitive control. This study is primarily designed to assess the efficacy of fNIRS-based NF training targeting the dlPFC for strengthening inhibitory control in patients with food addiction (FA) and obesity. METHODS: Fifty females eligible for obesity surgery and presenting FA will be recruited. The intervention will consist of eight fNIRS-based NF sessions over a month, with the first and last sessions conducted in combination with functional magnetic resonance imaging. Volunteers will be instructed to maintain as high as possible a visual gauge representing the real-time level of their dlPFC activity, by using their own mental strategies. Participants will be randomly assigned to either the "neurofeedback" group (n=25) or the "control" group (n=25; sham signal). Outcomes will include neuroimaging, clinical, fasting biological, and psychometric measures. These data will be compared between groups at baseline, just after the intervention, and three months post-intervention, except for neuroimaging measures. The primary endpoint will be the changes in cognitive control, assessed by variations in the cortico-striatal resting-state FC. CONCLUSION: This study protocol proposes a novel therapeutic approach for patients with obesity and FA. If NF proves to be effective in enhancing inhibitory control over eating behavior, this intervention could be proposed as part of the multidisciplinary obesity care pathway or for obesity prevention. TRIAL REGISTRATION: 2022 (Identifier: NCT05277714; URL: https://clinicaltrials.gov/study/NCT05277714).