title: Receptive vocabulary, expressive vocabulary, and speech production of boys with fragile X syndrome in comparison to boys with down syndrome.
abstract: Boys with fragile X syndrome with (n = 49) and without (n = 33) characteristics of autism spectrum disorder, boys with Down syndrome (39), and typically developing boys (n = 41) were compared on standardized measures of receptive vocabulary, expressive vocabulary, and speech administered annually over 4 years. Three major findings emerged. Boys with fragile X without autism spectrum disorder did not differ from the younger typically developing boys in receptive and expressive vocabulary and speech production when compared at similar levels of nonverbal cognitive skills. Boys with fragile X without autism spectrum disorder and typically developing boys had higher receptive vocabulary and speech production than did boys with Down syndrome. There were mixed patterns of results for the boys with fragile X and characteristics of autism spectrum disorder.
authors.affiliation: University of North Carolina at Chapel Hill, NC 27599-8180, USA. joanne_roberts@unc.edu
authors.forename: Joanne
authors.initials: J
authors.lastname: Roberts
authors.forename: Johanna
authors.initials: J
authors.lastname: Price
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Barnes
authors.forename: Lauren
authors.initials: L
authors.lastname: Nelson
authors.forename: Margaret
authors.initials: M
authors.lastname: Burchinal
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Hennon
authors.forename: Lauren
authors.initials: L
authors.lastname: Moskowitz
authors.forename: Anne
authors.initials: A
authors.lastname: Edwards
authors.forename: Cheryl
authors.initials: C
authors.lastname: Malkin
authors.forename: Kathleen
authors.initials: K
authors.lastname: Anderson
authors.forename: Jan
authors.initials: J
authors.lastname: Misenheimer
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Hooper
mesh_terms: D001184:Articulation Disorders / Q000175:diagnosis / Q000523:psychology; D001321:Autistic Disorder / Q000175:diagnosis / Q000523:psychology; D002675:Child, Preschool; D015897:Comorbidity; D004314:Down Syndrome / Q000175:diagnosis* / Q000523:psychology; D005500:Follow-Up Studies; D005600:Fragile X Syndrome / Q000175:diagnosis* / Q000523:psychology; D006801:Humans; D007805:Language Development Disorders / Q000175:diagnosis* / Q000523:psychology; D008297:Male; D013067:Speech Perception; D013068:Speech Production Measurement; D014705:Verbal Behavior; D014825:Vocabulary