Examining the Language Phenotype in Children With Typical Development, Specific Language Impairment, and Fragile X Syndrome

Abstract

Purpose: One aspect of morphosyntax, finiteness marking, was compared in children with fragile X syndrome (FXS), specific language impairment (SLI), and typical development matched on mean length of utterance (MLU). Method: Nineteen children with typical development (mean age = 3.3 years), 20 children with SLI (mean age = 4.9 years), and 17 boys with FXS (mean age = 11.9 years) completed the Test of Early Grammatical Impairment (TEGI; Rice & Wexler, 2001), and other cognitive and language assessments. Quantitative comparisons on finiteness marking and qualitative comparisons of unscorable (i.e., nontarget) TEGI responses were conducted. Results: Children with typical development and FXS performed better on finiteness marking than children with SLI. Although unscorable responses were infrequent, boys with FXS produced more unscorable responses than children with typical development and SLI. Conclusions: Although boys with FXS have language deficits, they performed similarly to MLU-matched typically developing children on finiteness marking. This language profile differs from children with SLI, who present with a delay-within-a-delay profile with finiteness marking delays that exceed delays in MLU. Unscorable responses produced by the boys with FXS may reflect pragmatic deficits, which are prominent in this population. Assessment procedures should be carefully considered when examining language in boys with FXS.

Exemplar Variability Facilitates Retention of Word Learning by Children With Specific Language Impairment

“…This study included children whose mean single-word vocabulary test scores were comparable to other recent samples of English-speaking preschool children with SLI (Fey, Leonard, Bredin-Oja, & Deevy, 2017;Haebig, Sterling, & Hoover, 2016;Meyers-Denman & Plante, 2016;Oetting, McDonald, Seidel, & Hegarty, 2016;Snowling, Duff, Nash, & Hulme, 2016;Vuolo, Goffman, & Zelaznik, 2017;Wray, Norbury, & Alcock, 2016). This suggests likely generalization to the broader SLI population.…”

Investigating the Receptive-Expressive Vocabulary Profile in Children with Idiopathic ASD and Comorbid ASD and Fragile X Syndrome

“…Due to the variability seen in females with FXS, we only included boys in the current study. Participants came from a larger study examining syntactic language in boys with ASD and boys with FXS (Haebig et al 2016). FXS was confirmed via previous molecular genetic testing and all boys with idiopathic ASD completed genetic testing to rule out FXS.…”

Grammar in Boys With Idiopathic Autism Spectrum Disorder and Boys With Fragile X Syndrome Plus Autism Spectrum Disorder

“…The study was limited to third-person singular and past tense markers, only used the TEGI, and did not provide a careful characterization of ASD symptoms, leaving open the question of the impact of an ASD codiagnosis on tense marking. Haebig et al (2016) extended this work to include copula and auxiliary "be," auxiliary forms of "do," thirdperson singular, and past tense markers. They compared the performance of school-age boys with FXS to children with specific language impairment (SLI) and languagematched children with typical development.…”

“…Participants were drawn from a larger study on language in boys with FXS and idiopathic ASD (Haebig & Sterling, 2017;Haebig et al, 2016). For the present analysis, groups were similar on MLU, t(35) = 1.12, p = .272, d = .36, variance ratio = .58, following the guidelines outlined in Kover and Atwood (2013).…”

“…T he use of spoken language is a fundamental aspect of human communication, and impairments at any level can result in lifelong struggles. In neurodevelopmental disorders, language is not only impaired but can also distinguish the phenotypes of different disorders (Finestack, Sterling, & Abbeduto, 2013;Haebig, Sterling, & Hoover, 2016). Comparative studies, including disorders of known and unknown etiology with similar behavioral phenotypes, are important both for clinical purposes as well as from a biological perspective.…”