Purpose: The current study addresses a gap in the literature regarding syntactic development of adolescent boys with fragile X syndrome (FXS) and Down syndrome (DS). Specifically, we ask whether syntactic skills plateau or continue to change during adolescence for these groups and whether the profile of syntactic change differs between boys with…

Vocal imitation in English-speaking autistic individuals has been shown to be atypical. Speaking a tone language such as Mandarin facilitates vocal imitation skills among non-autistic individuals, yet no studies have examined whether this effect holds for autistic individuals. To address this question, we compared vocal imitation of speech and…

Compared to their neurotypically developing peers, children and adolescents with autism spectrum disorders tend to have attenuated neural responses in the parietal lobe when attending sensory input, as reflected by a reduced P3b amplitude measured with electroencephalography. However, it is unknown whether a reduced P3b amplitude in autistic…

Approximately 3-4 boys for every girl meet the clinical criteria for autism in studies of community diagnostic patterns and studies of autism using samples of convenience. However, girls with autism have been hypothesized to be underdiagnosed, possibly because they may present with differing symptom profiles as compared to boys. This secondary…

Purpose: Despite the clinical utility of sentence production and sentence repetition to identify language impairment in autism, little is known about the extent to which these tasks are sensitive to potential language variation. One promising method is strategic scoring, which has good clinical utility for identifying language impairment in…

Autistic youth often experience challenges in interactions with neurotypical peers. One factor that may influence successful interactions with peers is interpersonal synchrony, or the degree to which interacting individuals align their behaviors (e.g. facial expressions) over time. Autistic and neurotypical youth were paired together into three…

Autistic people often experience difficulties navigating face-to-face social interactions. Historically, the empirical literature has characterised these difficulties as cognitive 'deficits' in social information processing. However, the empirical basis for such claims is lacking, with most studies failing to capture the complexity of social…

Motor stereotypies are frequently reported in individuals with autism spectrum disorder, but determinants of stereotypies remain poorly understood. In this study, a randomized sample of children with diagnosis of autism spectrum disorder was investigated to identify the prevalence and determinants of stereotypies. A total of 134 children who…

Successful social interactions are assumed to depend on theory of mind--the ability to represent others' mental states--yet most studies of the relation between theory of mind and social-interactive success rely on non-interactive tasks that do not adequately capture the "spontaneous" engagement of theory of mind, a crucial component of…

We report a Delphi Consensus modification and first validation study of the Autism Diagnostic Observation Schedule -- 2 with deaf children and young people (ADOS-2 Deaf adaptation). Validation included 122 deaf participants (aged 2-18 years), 63 with an Autism Spectrum Disorder (ASD). This was compared to a National Institute for Health and…

Background & Aims: Discourse markers, such as "well" or "like," serve a variety of functions to support conversational reciprocity: filling pauses, aiding word-finding, and modulating turn-taking by holding the conversational floor. Previous research shows that autistic individuals use discourse markers less frequently than…

Mental health conditions such as anxiety, depression, aggression, and inattention are common in autistic youth and are challenging to treat by community providers. We aim to parse the heterogeneity of autism based on dimensions of executive function and determine whether specific executive function profiles are differentially related to…

Background and aims: A substantial minority of autistic individuals score within typical ranges on standard language tests, suggesting that autism does not necessarily affect language acquisition. This idea is reflected in current diagnostic criteria for autism, wherein language impairment is no longer included. However, some work has suggested…

Purpose: Typical speakers tend to adopt words used by their conversational partners. This "lexical alignment" enhances communication by reducing ambiguity and promoting a shared understanding of the topic under discussion. Lexical alignment has been little studied to date in autism spectrum disorder (ASD); furthermore, it has been…

The current diagnostic criteria for the autism spectrum disorder (ASD) include the possibility to specify concomitant language difficulties. Purpose: Our main aim was to explore whether children with ASD-Level 1 (ASD-L1) present difficulties in the acquisition of structural language, as little work has been done in this regard so far. As a…