An MRI Study of Increased Cortical Thickness in Autism

Hardan, Antonio Y. M.D.
Muddasani, Sri M.D.
Vemulapalli, Madhuri M.S.
Keshavan, Matcheri S. M.D.
Minshew, Nancy J. M.D.

Stanford University; the Department of Psychiatry, The University of Texas Health Science Center, San Antonio; the Department of Psychiatry, Wayne State University, Detroit; and the Department of Psychiatry, University of Pittsburgh.

Address correspondence and reprint requests to Dr. Hardan, Stanford University, Department of Psychiatry and Behavioral Sciences, 401 Quarry Rd., Stanford, CA 94305; [email protected] (e-mail).

This study was supported by NIMH research grant MH-64027 (Dr. Hardan).

Received Dec. 9, 2004; revisions received March 4, March 28, and April 18, 2005; accepted April 25, 2005.

American Journal of Psychiatry 163(7):p 1290-1292, July 2006.

Objective

The purpose of this study was to examine cortical thickness in autism in light of the postmortem evidence of cortical abnormalities of the disorder.

Method

Magnetic resonance imaging (MRI) scans were acquired from 17 children with autism and 14 healthy comparison subjects, and sulcal and gyral thickness were measured for the total brain and for all lobes.

Results

Increases in total cerebral sulcal and gyral thickness were observed in children with autism relative to comparison subjects. Similar findings were noted in the temporal and parietal lobes but not in the frontal and occipital lobes.

Conclusions

These preliminary findings indicate that increased cortical thickness may contribute to the increased gray matter volume and total brain size that have been observed in autism and may also be related to anomalies in cortical connectivity.