A study by Lisa Ronan (Psychiatry) and Paul Fletcher (Psychiatry) has uncovered distinct differences in brain structure in obese children compared to those of normal weight.
Published in Cerebral Cortex, the study aimed to determine whether differences in brain structure mediate the relationship between executive function and childhood obesity. The researchers analysed MR-derived measures of cortical thickness for 2700 children between the ages of 9 and 11 years, recruited as part of the NIH Adolescent Brain and Cognitive Development (ABCD) study. The researchers related their findings to measures of executive function and body mass index (BMI).
In their analysis, increased BMI was associated with significantly reduced mean cortical thickness, as well as specific bilateral reduced cortical thickness in prefrontal cortical regions. This relationship remained after accounting for age, sex, race, parental education, household income, birth-weight, and in-scanner motion. Increased BMI was also associated with lower executive function.
These results suggest that childhood obesity is associated with compromised executive function. The data are consistent with a mechanism whereby prefrontal cortex changes in childhood obesity may lead to altered regulation of inhibitory control and risk-taking behaviour and further difficulties in weight control. The researchers highlight that follow-up studies will be critical to establishing causal pathways between BMI, brain structure, and executive function, as well as determining if longitudinal changes in BMI have a measurable impact on these traits.
