GYRI MALFORMATIONS

   MRI studies showed a high incidence of gyri malformations in autistic subjects, while none were detectable in controls (Piven et al, 1990). Out of 13 autistic subjects, five had polymicrogyria, one had schizencephaly and macrogyria, and one had macrogyria.

   Right anterior cingulate area 24' was significantly smaller in relative
volume, and both area 24 and area 24' were metabolically less active, in autistic patients than in the normal subjects (Haznedar et al, 1997).

   In hypothyroid rats the volume of the granular layer and the numerical density of its neurons were reduced, the total number of granule cells was decreased (Madeira et al, 1991).

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Haznedar MM, Buchsbaum MS, Metzger M, Solimando A, Spiegel-Cohen J, Hollander E - "Anterior cingulate gyrus volume and glucose metabolism in autistic disorder" Am J Psychiatry 154(8):1047-50 (1997) http://www.ncbi.nlm.nih.gov/htbin-post/Entrez/query?uid=9247387&form=6&db=m&Dopt=r

Madeira MD, Cadete-Leite A, Andrade JP, Paula-Barbosa MM - "Effects of hypothyroidism upon the granular layer of the dentate gyrus in male and female adult rats: a morphometric study" J Comp Neurol 314(1):171-86 (1991) http://www.ncbi.nlm.nih.gov/htbin-post/Entrez/query?uid=1797872&form=6&db=m&Dopt=r

Piven J, Arndt S, Bailey J, Andreasen N -"Regional brain enlargement in autism - a magnetic resonance imaging study" J Am Acad Child Adolesc Psychiatry 35(4):530-6 (1996) http://www.ncbi.nlm.nih.gov/htbin-post/Entrez/query?uid=8919716&form=6&db=m&Dopt=r