An MRI study of brain size in autism

Am J Psychiatry. 1995 Aug;152(8):1145-9. doi: 10.1176/ajp.152.8.1145.


Objective: This study was undertaken to obtain detailed measurements of the volume of the brain, using magnetic resonance imaging (MRI), in a carefully selected group of autistic subjects and comparison subjects.

Method: Twenty-two male autistic subjects and 20 male volunteer comparison subjects were examined with detailed (1.5-mm slices) MRI throughout the entire brain. Total brain, total brain tissue, and total lateral ventricle volumes were measured by using manual tracing and automated techniques.

Results: After height and performance IQ were controlled, autistic subjects had significantly greater total brain, total tissue, and total lateral ventricle volumes than comparison subjects.

Conclusions: These findings suggest that male autistic subjects have enlarged brains and that enlargement is a result of both greater brain tissue volume and greater lateral ventricle volume.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Autistic Disorder / diagnosis*
  • Body Height
  • Brain / anatomy & histology*
  • Cerebral Ventricles / anatomy & histology
  • Humans
  • Intelligence
  • Magnetic Resonance Imaging*
  • Male
  • Sex Factors