Enlarged Striatum in Abstinent Methamphetamine Abusers: A Possible Compensatory Response

Biol Psychiatry. 2005 May 1;57(9):967-74. doi: 10.1016/j.biopsych.2005.01.039.

Abstract

Background: Little is known about structural brain abnormalities associated with methamphetamine (METH) abuse; therefore, we aimed: 1) to evaluate possible morphometric changes, especially in the striatum of recently abstinent METH-dependent subjects; 2) to evaluate whether morphometric changes are related to cognitive performance; and 3) to determine whether there are sex-by-METH interactions on morphometry.

Methods: Structural MRI was performed in 50 METH and 50 comparison subjects with the same age range and sex proportion; quantitative morphometric analyses were performed in the subcortical gray matter, cerebellum and corpus callosum. Neuropsychological tests were also performed in 44 METH and 28 comparison subjects.

Results: METH users showed enlarged putamen (left: + 10.3%, p = .0007; right: + 9.6%, p = .001) and globus pallidus (left: + 9.3%, p = .002; right: + 6.6%, p = .01). Female METH subjects additionally showed larger mid-posterior corpus callosum (+ 9.7%, p = .05). Although METH users had normal cognitive function, those with smaller striatal structures had poorer cognitive performance and greater cumulative METH usage.

Conclusions: Since METH subjects with larger striatal structures had relatively normal cognitive performance and lesser cumulative METH usage, the enlarged putamen and globus pallidus might represent a compensatory response to maintain function. Possible mechanisms for the striatal enlargement include glial activation and inflammatory changes associated with METH-induced injury.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Amphetamine-Related Disorders / pathology*
  • Amphetamine-Related Disorders / physiopathology*
  • Analysis of Variance
  • Brain Mapping
  • Case-Control Studies
  • Female
  • Functional Laterality
  • Humans
  • Image Processing, Computer-Assisted / methods
  • Magnetic Resonance Imaging / methods
  • Male
  • Methamphetamine*
  • Middle Aged
  • Neostriatum / drug effects
  • Neostriatum / pathology*
  • Neostriatum / physiopathology
  • Neuropsychological Tests
  • Problem Solving / physiology
  • Psychomotor Performance / physiology
  • Reaction Time / physiology
  • Sex Factors
  • Statistics as Topic
  • Verbal Learning / physiology

Substances

  • Methamphetamine