Abnormal brain size effect on the thalamus in autism

Hardan, Antonio Y.; Girgis, Ragy R.; Adams, Jason; Gilbert, Andrew R.; Keshavan, Matcheri S.; Minshew, Nancy J.

doi:10.1016/j.pscychresns.2005.12.009

« Previous Next »Psychiatry Research: Neuroimaging
Volume 147, Issue 2 , Pages 145-151, 30 October 2006

Abnormal brain size effect on the thalamus in autism

Antonio Y. Hardan
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Corresponding author. Department of Psychiatry, Western Psychiatric Institute and Clinic, 3811 O'Hara St., Pittsburgh, PA 15213, United States. Tel.: +1 412 246 6797; fax: +1 412 235 5446.
Ragy R. Girgis
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Department of Psychiatry, College of Physicians and Surgeons, Columbia University, and New York State Psychiatric Institute, New York, NY, USA
Jason Adams
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
Andrew R. Gilbert
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
Matcheri S. Keshavan
- Department of Psychiatry, Wayne State University, Detroit, MI, USA
Nancy J. Minshew
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA

Received 4 August 2005; received in revised form 16 December 2005; accepted 31 December 2005.

Abstract

This study was conducted to examine the volume of the thalamus in autism and to investigate the effect of brain size on this structure in an attempt to replicate, in a larger sample, findings from a previous study reporting the existence of a relationship between brain volume and thalamus in healthy controls but not in individuals with autism. Additionally, the relationships between thalamic volumes and clinical features were examined. Volumetric measurements of the right and left thalamic nuclei were performed on MRI scans obtained from 40 high-functioning individuals with autism (age range: 8–45 years) and 41 healthy controls (age range: 9–43 years). No differences were observed between the two groups for unadjusted thalamic volumes. However, the expected linear relationship between TBV and thalamic volume was not observed in individuals with autism. Furthermore, no correlations were observed between thalamic volumes and clinical features. Findings from this larger study are consistent with the previous report of an abnormal brain size effect on the thalamus in autism and support the possibility of abnormal connections between cortical and subcortical structures in this disorder.

Keywords: Thalamus, Autism, MRI, Brain volume, Structural neuroimaging