Reduced thickness of medial orbitofrontal cortex in smokers

Biol Psychiatry. 2010 Dec 1;68(11):1061-5. doi: 10.1016/j.biopsych.2010.08.004. Epub 2010 Sep 27.


Background: Structural deficiencies within the prefrontal cortex might be related to drug-taking behavior that prevails in smokers. Cortical thickness has been found to be a structural modulator of cerebral function and cognition and a subtle correlate of mental disorders. However, to date an analysis of cortical thickness in smokers compared with never-smokers has not been undertaken.

Methods: We acquired high-resolution magnetic resonance imaging scans from 22 smokers and 21 never-smokers and used FreeSurfer to model the gray-white and pial surfaces for each individual cortex to compute the distance between these surfaces to obtain a measure of cortical thickness. The main cortical folds were aligned across individuals with FreeSurfer's surface-based averaging technique to compare whole brain differences in cortical thickness between smokers and never-smokers.

Results: Relative to never-smokers, smokers showed greater cortical thinning in the left medial orbitofrontal cortex (mOFC). Cortical thickness measures extracted from mOFC correlated negatively with the amount of cigarettes consumed/day and the magnitude of lifetime exposure to tobacco smoke.

Conclusions: The brains of smokers are structurally different from those of never-smokers in a dose-dependent manner. The cortical thinning in mOFC in smokers relative to never-smokers might imply dysfunctions of the brain's reward, impulse control, and decision-making circuits. Related behavioral correlates are suggested to be relevant for smoking initiation and maintenance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Atrophy / pathology
  • Brain Mapping
  • Female
  • Frontal Lobe / pathology*
  • Humans
  • Image Processing, Computer-Assisted
  • Magnetic Resonance Imaging
  • Male
  • Smoking / pathology*