Obesity-specific circuits in the human brain: exploration by dynamic Brain Self-Reference (dynBSR)

Horm Metab Res. 2006 Dec;38(12):777-82. doi: 10.1055/s-2006-958629.

Abstract

In the last decade many efforts have been made in order to identify brain regions that may be abnormal in obese subjects. Most of the lines of research have examined links between brain circuits, behavioral processing, and overweight. We introduce here a novel analysis to the brain mapping, 'dynamic Brain Self-Reference' (dynBSR), based on the electrical response evoked during passively viewing a simple stimulus. Hypothetically, it should be possible to monitor both task-related networks and task-irrelevant networks during a mental state with low cognitive demand, as shown previously by others using fMRI and establishing the latter as the neural correlates of an 'inherent' brain activation pattern. However, this fact has been usually ignored. Our results showed that a distinct set of interconnected brain regions including, frontal areas (middle, inferior, orbitofrontal, and dorsolateral), dorsal/ventral striatum, thalamus, superior temporal region, insula cortex, post-central gyrus, left supramarginal gyrus, and parietal regions, whose activities seem to be tonically maintained, displays cohesive functional state in obesity during passively viewing a simple stimulus. This organized network is maintained in a dynamic equilibrium with the transient activation of the right supramarginal gyrus. These brain areas have been previously implicated in the regulation of taste, reward, and behavioral processing and most of them have also structural abnormalities regarding normal-weight subjects. Although exploratory, the most important result here is that the evaluation of the visual-evoked responses with dynBSR provides a foundation for investigating the brain circuits in obesity, and becomes the first attempt, to our knowledge, to imply task-irrelevant networks in these individuals.

Publication types

  • Controlled Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Brain / physiology*
  • Brain Mapping / methods*
  • Evoked Potentials, Visual / physiology
  • Humans
  • Imaging, Three-Dimensional
  • Obesity / psychology*