Positron emission tomography of the cerebellum in autism

On the basis of neurological evidence that autistic patients have fewer Purkinje and granule cells in the cerebellum as well as vermal cerebellar hypoplasia, the authors tested the hypothesis that autistic patients have cerebellar hypofunctioning. They used positron emission tomography of the cerebellum with 18F-labeled 2-deoxyglucose to study seven autistic patients and eight age-matched control subjects. The results showed no significant difference in mean cerebellar glucose metabolism between the two groups, but all mean glucose rates of the autistic patients were either equal to or greater than those of the control subjects. The implications of these findings are discussed.

Pneumographic findings in the infantile autism syndrome. A correlation with temporal lobe disease

Pneumoencephalographic findings are described in a group of 18 children who presented to us with a history of retarded language development and autistic behaviour disturbances. None had specific diagnosable neurological diseases nor gross motor disorders. PEG findings included, most prominently, pathological enlargement of the left temporal horn in 15 cases; some cases showed enlargement of both temporal horns or mild variable enlargement of the lateral ventricles, especially the left. Comparisons between infantile autism and recognized patterns of temporal lobe disease (especially Korsakoff syndrome and Kluver-Bucy syndrome) are drawn. We have suggested that medial temporal lobe dysfunction may be a major factor in the pathogenesis of the syndrome of infantile autism.