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…

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…

Purpose: Most assessment tools used to diagnose and characterize autism spectrum disorder (ASD) were developed for in-person administration. The coronavirus disease 2019 (COVID-19) pandemic resulted in the need to adapt traditional assessment tools for online administration with only minimal evidence to support validity of such practices. Methods:…

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…

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…

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: As evidenced by perceptual learning studies involving adult listeners and speakers with dysarthria, adaptation to dysarthric speech is driven by signal predictability (speaker property) and a flexible speech perception system (listener property). Here, we extend adaptation investigations to adolescent populations and examine whether adult…

The current study characterized the impact of the COVID-19 pandemic and stay-at-home orders on adolescents' internalizing symptoms and assessed predictors of adolescents' internalizing symptoms during the pandemic. Seventy-nine adolescents (18 autistic, 61 nonautistic) and their parents who participated in a previous study and were at least 10…

Purpose: In the context of music and speech perception, this study aimed to assess the effect of variation in one of two auditory attributes--pitch contour and timbre--on the perception of the other in prelingually deafened young cochlear implant (CI) users, and the relationship between pitch contour perception and two cognitive functions of…

Background/Objective: Researchers have traditionally reported that individuals with Down syndrome possess a strength in their social development, yet the opposite occurs with Asperger's syndrome. Based on this premise, we sought to assess effectiveness of the social skills training program. Method: Thirty adolescents aged 11 to 14 years with Down…

Neurotypical adults often form negative first impressions of individuals with autism spectrum disorder and are less interested in engaging with them socially. In contrast, individuals with autism spectrum disorder actively seek out the company of others who share their diagnosis. It is not clear, however, whether individuals with autism spectrum…

Attachment difficulties are associated with a range of adverse outcomes in mental health, and people with intellectual disabilities (IDs) may be at greater risk of experiencing difficulties in their attachment relationships. This review critically evaluated recent research measuring the prevalence of attachment difficulties in people with ID.…

The relation between metabolic control (HbA1c) and achievement (grade point average [GPA]) was examined over a period of 2.5 years (every 6 months) employing a dynamical systems approach that allowed for the examination of whether HbA1c was associated with change in subsequent GPA and vice versa. Metabolic control tends to deteriorate (i.e., with…

Repetitive behaviors are observed in autism spectrum disorder and obsessive-compulsive disorder. Clinically, obsessive-compulsive disorder obsessions are thought to drive repetitive or ritualistic behavior designed to neutralize subjective distress, while restricted and repetitive behaviors are theorized to be reward- or sensory-driven. Both…

Atypical social communication is a key indicator of autism spectrum disorder and has long been presumed to interfere with friendship formation and first impressions among typically developing youth. However, emerging literature suggests that such atypicalities may function differently among groups of peers with autism spectrum disorder. The…