ANTERIOR CINGULATE GYRUS VOLUME AND GLUCOSE-METABOLISM IN AUTISTIC DISORDER

Objective: This study reports the first paired measurements of glucose metabolism and volume of the anterior cingulate gyrus in autism. Meth od: Magnetic resonance imaging (MRI) and positron emission tomography (PET) scans of seven high-functioning autistic patients and seven sex- and age-matched normal volunteers were coregistered. After the anteri or cingulate gyri were outlined on the MRI images, the volumes of the structures were measured and corrected for brain volume. The volumes w ere then applied to the PET images and metabolic maps were obtained. R esults: Right anterior cingulate area 24' was significantly smaller in relative volume, and both area 24 and area 24' were metabolically les s active, in the autistic patients than in the normal subjects. Conclu sions: Autism may be characterized by structural and functional altera tions in the anterior cingulate gyrus.