title: Decreased pyramidal neuron size in Brodmann areas 44 and 45 in patients with autism.
abstract: Autism is a neurodevelopmental disorder characterized by deficits in social interaction and social communication, as well as by the presence of repetitive and stereotyped behaviors and interests. Brodmann areas 44 and 45 in the inferior frontal cortex, which are involved in language processing, imitation function, and sociality processing networks, have been implicated in this complex disorder. Using a stereologic approach, this study aims to explore the presence of neuropathological differences in areas 44 and 45 in patients with autism compared to age- and hemisphere-matched controls. Based on previous evidence in the fusiform gyrus, we expected to find a decrease in the number and size of pyramidal neurons as well as an increase in volume of layers III, V, and VI in patients with autism. We observed significantly smaller pyramidal neurons in patients with autism compared to controls, although there was no difference in pyramidal neuron numbers or layer volumes. The reduced pyramidal neuron size suggests that a certain degree of dysfunction of areas 44 and 45 plays a role in the pathology of autism. Our results also support previous studies that have shown specific cellular neuropathology in autism with regionally specific reduction in neuron size, and provide further evidence for the possible involvement of the mirror neuron system, as well as impairment of neuronal networks relevant to communication and social behaviors, in this disorder.
authors.affiliation: Fishberg Department of Neuroscience, Mount Sinai School of Medicine, One Gustave L. Levy Place, Box 1065, New York, NY 10029, USA.
authors.forename: Sarah
authors.initials: S
authors.lastname: Jacot-Descombes
authors.forename: Neha
authors.initials: N
authors.lastname: Uppal
authors.forename: Bridget
authors.initials: B
authors.lastname: Wicinski
authors.forename: Micaela
authors.initials: M
authors.lastname: Santos
authors.forename: James
authors.initials: J
authors.lastname: Schmeidler
authors.forename: Panteleimon
authors.initials: P
authors.lastname: Giannakopoulos
authors.forename: Helmut
authors.initials: H
authors.lastname: Heinsen
authors.forename: Helmut
authors.initials: H
authors.lastname: Heinsein
authors.forename: Christoph
authors.initials: C
authors.lastname: Schmitz
authors.forename: Patrick R
authors.initials: PR
authors.lastname: Hof
mesh_terms: D000328:Adult; D000368:Aged; D001321:Autistic Disorder / Q000473:pathology* / Q000503:physiopathology*; D002452:Cell Count / Q000379:methods; D048429:Cell Size; D002648:Child; D002675:Child, Preschool; D005260:Female; D005625:Frontal Lobe / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D017966:Pyramidal Cells / Q000473:pathology*; D013238:Stereotaxic Techniques; D055815:Young Adult