Elevated body mass index in youth is associated with neural disinhibition and internetwork functional dysconnectivity: A magnetoencephalography study.

OBJECTIVE

The developing brain has a vulnerability to the negative impact of obesity and excessive consumption of hyperpalatable foods. Animal models suggest changes in the excitation:inhibition balance of the brain in obesogenic diets, including disinhibition and hyperexcitability, and altered connectivity between brain regions.

METHODS

We investigated the neurophysiological effects of overweight and obesity in 32youth (8-19 years), using a naturalistic viewing protocol with magnetoencephalography (MEG). Subjects were recruited into two groups based on normalised / z-scored body mass index (zBMI), a < 1 SD group (n = 15) and ≥ 1 SD group (n = 17). We assessed spontaneous oscillatory activity and aperiodic components (spectral exponent and offset) and network functional connectivity.

RESULTS

Elevated zBMI was associated with significant increases in gamma activity, as well as a reduced exponent and offset across multiple regions, which suggest changes in neural excitation and inhibition. Additionally, we observed low frequency hypoconnectivity and high frequency hyperconnectivity between multiple brain networks.

CONCLUSIONS

These findings underscore the neural impact of body composition on the developing brain, suggesting deleterious alterations in excitation and inhibition and brain networks linked with cognition and behaviour.

SIGNIFICANCE: These alterations may contribute to the persistent behavioural rigidity and difficulties in adopting healthier eating behaviours into adulthood.