title: Convergent neuroanatomical and behavioural evidence of an amygdala hypothesis of autism.
abstract: In this study we report a convergence of behavioural and neuroanatomical evidence in support of an amygdala hypothesis of autism. We find that people with high-functioning autism (HFA) show neuropsychological profiles characteristic of the effects of amygdala damage, in particular selective impairment in the recognition of facial expressions of fear, perception of eye-gaze direction, and recognition memory for faces. Using quantitative magnetic resonance (MR) image analysis techniques, we find that the same individuals also show abnormalities of medial temporal lobe (MTL) brain structure, notably bilaterally enlarged amygdala volumes. These results combine to suggest that developmental malformation of the amygdala may underlie the social-cognitive impairments characteristic of HFA. This malformation may reflect incomplete neuronal pruning in early development.
authors.affiliation: Magnetic Resonance and Image Analysis Research Centre, University of Liverpool, UK.
authors.forename: M A
authors.initials: MA
authors.lastname: Howard
authors.forename: P E
authors.initials: PE
authors.lastname: Cowell
authors.forename: J
authors.initials: J
authors.lastname: Boucher
authors.forename: P
authors.initials: P
authors.lastname: Broks
authors.forename: A
authors.initials: A
authors.lastname: Mayes
authors.forename: A
authors.initials: A
authors.lastname: Farrant
authors.forename: N
authors.initials: N
authors.lastname: Roberts
mesh_terms: D000293:Adolescent; D000328:Adult; D000679:Amygdala / Q000002:abnormalities / Q000473:pathology* / Q000503:physiopathology*; D001321:Autistic Disorder / Q000209:etiology* / Q000473:pathology* / Q000503:physiopathology; D019260:Expressed Emotion / Q000502:physiology; D005149:Facial Expression; D005403:Fixation, Ocular / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008569:Memory Disorders / Q000209:etiology / Q000473:pathology / Q000503:physiopathology; D009483:Neuropsychological Tests; D010364:Pattern Recognition, Visual / Q000502:physiology; D012920:Social Behavior Disorders / Q000209:etiology* / Q000473:pathology* / Q000503:physiopathology