Reduced brainstem size in children with autism.

Recently, structural brain abnormalities as well as functional abnormalities of the brainstem have been reported in autistic children. The authors undertook an analytic study of the brainstem in autistic children by means of magnetic resonance imaging (MRI). The MRI scans of 29 autistic children were compared with 15 control MRI scans. The autistic children were divided into two groups according to DQ (IQ) level: the DQ (IQ) greater than or equal to 80 group and the DQ (IQ) less than 80 group. The midbrain and pons were measured, and the ratio of the midbrain and pons sizes versus the cranium size were calculated. The brainstem size was found to be significantly smaller in the autistic group. In particular, the reduction in brainstem size tended to be greater in the low DQ (IQ) group when compared with the high DQ (IQ) one, though there was no significant difference (p less than 0.1). This suggests that the brainstem is anatomically altered in autistic children.