An MRI Study of Brain Size in Autism

Piven, Joseph
Arndt, Stephan
Bailey, James
Havercamp, Susan
Andreasen, Nancy C.
Palmer, Pat

Received July 20, 1994; revision received March 3, 1995; accepted April 4, 1995. From the Department of Psychiatry, University of Iowa College of Medicine. Address reprint requests to Dr. Piven, 1875 John Pappajohn Pavilion, Child and Adolescent Psychiatry Clinic, University of Iowa Hospitals and Clinics, Iowa City, IA 52242-1057.
Supported in part by a March of Dimes Clinical Research Grant (Dr. Piven) and NIMH grants MH-51217 and MH-01028 to Dr. Piven and MH-40856 and MH-43271 to Dr. Andreasen.

American Journal of Psychiatry 152(8):p 1145-1149, August 1995.

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. (Am J Psychiatry 1995; 152:1145-1149)