a1 Child Study Center and Investigative Medicine Program, Yale University School of Medicine, New Haven, CT, USA
a2 Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
a3 Department of Psychiatry, Beth Israel and Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
a4 Department of Psychiatry and Behavioral Science, Stanford University School of Medicine, Stanford, CA, USA
Background Although several studies have examined brainstem volume in autism, results have been mixed and no investigation has specifically measured gray- and white-matter structures. The aim of this investigation was to assess gray- and white-matter volumes in children with autism.
Method Subjects included 22 right-handed, non-mentally retarded boys with autism and 22 gender- and age-matched controls. Magnetic resonance imaging (MRI) scans were obtained using a 1.5-T scanner and volumetric measurements were performed using the BRAINS2 software package. Gray- and white-matter volumes were measured using a semi-automated segmentation process.
Results There were no significant differences in age and total brain volume (TBV) between the two groups but full-scale IQ was higher in controls. A decrease in brainstem gray-matter volume was observed in the autism group before and after controlling for TBV. No significant differences were observed in white-matter volume. A significant relationship was observed between brainstem gray-matter volume and oral sensory sensitivity as measured by the Sensory Profile Questionnaire (SPQ).
Conclusions Findings from this study are suggestive of brainstem abnormalities in autism involving gray-matter structures with evidence supporting the existence of a relationship between these alterations and sensory deficits. These results are consistent with previous investigations and support the existence of disturbances in brainstem circuitry thought to be implicated in the sensory dysfunction observed in autism.
(Received January 02 2008)
(Revised July 02 2008)
(Accepted July 30 2008)
(Online publication September 24 2008)
c1 Address for correspondence: A. Y. Hardan, M.D., Department of Psychiatry and Behavioral Science, Stanford University School of Medicine, 401 Quarry Road, Stanford, CA 94305, USA. (Email: [email protected])