This longitudinal study examined pragmatic language in boys and girls with Down syndrome (DS) at up to three time points, using parent report, standardized and direct assessments. We also explored relationships among theory of mind, executive function, nonverbal mental age, receptive and expressive vocabulary, grammatical complexity, and pragmatic…

Purpose: Pragmatic language skills are often impaired above and beyond general language delays in individuals with neurodevelopmental disabilities. This study used a multimethod approach to language sample analysis to characterize syndrome- and sex-specific profiles across different neurodevelopmental disabilities and to examine the congruency of…

Purpose: The ability to repair breakdowns in communication is an important pragmatic language skill that helps to maintain clear and meaningful interactions. Examining this ability in genetically based neurodevelopmental disabilities in which pragmatics are affected can provide important information about the precise pragmatic skills impacted…

Background: This study is a longitudinal follow-up to prior work examining the important pragmatic skill of communication repair (i.e., the ability to respond effectively to a request for clarification of an unclear message) across three neurodevelopmental disabilities in which language skills are impaired: fragile X syndrome with and without…

Purpose: Impaired pragmatic language (i.e., language use for social interaction) is a hallmark feature of both autism spectrum disorder (ASD) and fragile X syndrome (FXS), the most common known monogenic disorder associated with ASD. However, few cross-population comparisons of ASD and FXS have been conducted, and it is unclear whether pragmatic…

This study tested the hypothesis that pragmatic (i.e., social) language impairment is linked to arousal dysregulation in autism spectrum disorder (ASD) and fragile X syndrome (FXS). Forty boys with ASD, 39 with FXS, and 27 with typical development (TD), aged 4-15 years, participated. Boys with FXS were hyperaroused compared to boys with TD but did…

Background: Fragile X syndrome (FXS) and Down syndrome (DS) are the two leading genetic causes of intellectual disability, and FXS is the most common known genetic condition associated with autism. Both FXS and DS are associated with significant language impairment, but little is known about expressive language across domains over time or the role…

While there is a strong sex bias in the presentation of autism, it is unknown whether this bias is also present in subclinical manifestations of autism among relatives, or the broad autism phenotype. This study examined this question and investigated patterns of co-occurrence of broad autism phenotype traits within families of individuals with…

Whereas pragmatic language difficulties are characteristic of both autism and Fragile X syndrome, it is unclear whether such deficits are qualitatively similar or whether certain skills are differentially affected. This study compared narrative competence in boys with autism, Fragile X syndrome, Down syndrome, and typical development. Results…

Background: Strong evidence from twin and family studies suggests that the genetic liability to autism may be expressed through personality and language characteristics qualitatively similar, but more subtly expressed than those defining the full syndrome. This study examined behavioral features of this "broad autism phenotype" (BAP) in relation…

The broad autism phenotype (BAP) is a set of personality and language characteristics that reflect the phenotypic expression of the genetic liability to autism, in non-autistic relatives of autistic individuals. These characteristics are milder but qualitatively similar to the defining features of autism. A new instrument designed to measure the…

Efficient neural encoding of sound plays a critical role in speech and language, and when impaired, may have reverberating effects on communication skills. This study investigated disruptions to neural processing of temporal and spectral properties of speech in individuals with ASD and their parents and found evidence of inefficient temporal…