Altered resting-state functional connectivity of medial frontal cortex in overweight individuals: Link to food-specific intentional inhibition and weight gain

Numerous findings from functional neuroimaging research suggest that overweight may be associated with al-terations in reactive inhibition. However, there is a dearth of research investigating the functional connectivity that mediates intentional inhibition in overweight individuals. To explore this issue, 55 overweight and 45 normal-weight adults completed an assessment consisting of a resting-state functional magnetic resonance im-aging scan, a behavioural task measuring food-specific intentional inhibition, and a 1-year longitudinal mea-surement of BMI change. A seed-based approach was employed to examine the group-difference of the resting -state functional connectivity (rsFC) of the medial frontal cortex (MFC) (dorsal fronto-medial cortex [dFMC], pre -supplementary motor area, and premotor cortex) regions involved in intentional inhibition. Compared with normal-weight adults, the overweight individuals exhibited higher rsFC between the MFC seeds and (i) cere-bellum, (ii) postcentral gyrus, (iii) middle temporal gyrus, and (iv) posterior cingulate cortex, while lower rsFC strength were observed between MFC seeds and (i) putamen and (ii) insula. The overweight individuals with higher dFMC-cerebellum rsFC strength showed poorer performance in food-specific intentional inhibition and gained more weight a year later than those of normal-weight participants. Results suggested that altered func-tional connections between MFC and regions associated with reward and maladaptive eating may be key neural mechanisms of food-specific intentional inhibition in overweight status. Therefore, individuals are encouraged to make informed decisions about their health and reduce their consumption of obesogenic foods from the perspective of intentional inhibition.

Automated summary

Functional neuroimaging research suggests that overweight individuals may have alterations in reactive inhibition. However, little is known about the functional connectivity that mediates intentional inhibition in overweight individuals. This study found that compared to normal-weight adults, overweight individuals exhibited different patterns of functional connectivity between the medial frontal cortex and other brain regions involved in intentional inhibition. These altered functional connections were associated with poorer performance in food-specific intentional inhibition and weight gain over time.