title: Inflectional morphology in high-functioning autism: Evidence for speeded grammatical processing.
abstract: Autism is characterized by language and communication deficits. We investigated grammatical and lexical processes in high-functioning autism by contrasting the production of regular and irregular past-tense forms. Boys with autism and typically-developing control boys did not differ in accuracy or error rates. However, boys with autism were significantly faster than controls at producing rule-governed past-tenses (slip-slipped, plim-plimmed, bring-bringed), though not lexically-dependent past-tenses (bring-brought, squeeze-squeezed, splim-splam). This pattern mirrors previous findings from Tourette syndrome attributed to abnormalities of frontal/basal-ganglia circuits that underlie grammar. We suggest a similar abnormality underlying language in autism. Importantly, even when children with autism show apparently normal language (e.g., in accuracy or with diagnostic instruments), processes and/or brain structures subserving language may be atypical in the disorder.
authors.affiliation: San Diego State University.
authors.forename: Matthew
authors.initials: M
authors.lastname: Walenski
authors.affiliation: Kennedy Krieger Institute, Johns Hopkins University School of Medicine.
authors.forename: Stewart H
authors.initials: SH
authors.lastname: Mostofsky
authors.affiliation: Georgetown University.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Ullman
keywords: autism; basal-ganglia; language; morphology; past tense; procedural memory