MRI neuroanatomy in young girls with autism: a preliminary study.
OBJECTIVE
To test the hypothesis that young girls and boys with autism exhibit different profiles of neuroanatomical abnormality relative to each other and relative to typically developing children.


METHODS
Structural magnetic resonance imaging was used to measure gray and white matter volumes (whole cerebrum, cerebral lobes, and cerebellum) and total brain volume in nine girls (ages 2.29-5.16) and 27 boys (ages 1.96-5.33) with autism and 14 girls (ages 2.17-5.71) and 13 boys (ages 1.72-5.50) with typical development. Structure size and the relationship between size and age were examined. Diagnostic and cognitive outcome data were obtained after the children reached 4 to 5 years of age.


RESULTS
Girls with autism exhibited nearly every size-related abnormality exhibited by boys with autism. Furthermore, additional sites of abnormality were observed in girls, including enlargement in temporal white and gray matter volumes and reduction in cerebellar gray matter volume. Significant correlations were observed between age and white matter volumes (e.g., cerebral white matter rs = 0.950) for the girls with autism, whereas no significant age-structure size relationships were observed for the boys with autism.


CONCLUSIONS
Results suggest sex differences in etiological factors and the biological time course of the disorder.
Bloss
Cinnamon S
CS
Ms. Bloss is with San Diego State University and the University of California, San Diego Joint Doctoral Program in Clinical Psychology, and Dr. Courchesne is with the Department of Neurosciences, University of California San Diego and Children's Hospital Research Center. Electronic address: cinnamon@ucsd.edu.
Courchesne
Eric
E
Ms. Bloss is with San Diego State University and the University of California, San Diego Joint Doctoral Program in Clinical Psychology, and Dr. Courchesne is with the Department of Neurosciences, University of California San Diego and Children's Hospital Research Center.
D000367:Age Factors; D001321:Autistic Disorder / Q000473:pathology*; D002531:Cerebellum / Q000473:pathology*; D002540:Cerebral Cortex / Q000473:pathology*; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D009445:Neuroanatomy; D009929:Organ Size; D012737:Sex Factors