The main aims of the current research were to determine when children develop a temporally extended self (TES) and what factors contribute to its development. However, in order to address these aims it was important to, first, assess whether the test of delayed self-recognition (DSR) is a valid measure for the development of the TES, and, second,…

Sensory symptoms are prevalent in autism spectrum disorder but little is known about the early developmental patterns of these symptoms. This study examined the development of sensory symptoms and the relationship between sensory symptoms and adaptive functioning during early childhood. Three groups of children were followed across three time…

This study investigated the development of novel metaphor and metonymy comprehension in both typically developing (TD) children and individuals with Williams syndrome (WS). Thirty-one TD children between the ages of 3;09 and 17;01 and thirty-four individuals with WS between the ages of 7;01 and 44 years old were administered a newly developed task…

The ability to flexibly adapt to the changing demands of the environment is often reported as a core deficit in fragile X syndrome (FXS). However, the cognitive processes that determine this attentional set-shifting deficit remain elusive. The present study investigated attentional set-shifting ability in fragile X syndrome males with the…

Aberrant attention is a core feature of fragile X syndrome (FXS), however, little is known regarding the developmental trajectory and underlying physiological processes of attention deficits in FXS. Atypical visual attention is an early emerging and robust indicator of autism in idiopathic (non-FXS) autism. Using a biobehavioral approach with gaze…

The present study examined narrative development in children and adolescents with Down syndrome longitudinally. Narratives were collected from 32 children and adolescents with Down syndrome three times over a 1-year period. Both micro- and macrolevel analyses were conducted. Significant growth over the 1-year period was seen in semantic complexity…

Daily living skills (DLS), such as personal hygiene, meal preparation, and money management, are important to independent living. Research suggests that many individuals with autism spectrum disorder exhibit impairments in daily living skills relative to their cognitive skills. This study examined predictors of daily living skills attainment and…

We observed infant siblings of children with autism later diagnosed with ASD (ASD siblings; n = 17), infant siblings of children with autism with and without other delays (Other Delays and No Delays siblings; n = 12 and n = 19, respectively) and typically developing controls (TD controls; n = 19) during a free-play task at 18 months of age.…

The Perceptions of Children's Theory of Mind Measure (Experimental version; PCToMM-E) is an informant measure designed to tap children's theory of mind competence. Study one evaluated the measure when completed by primary caregivers of children with autism spectrum disorder. Scores demonstrated high test-retest reliability and correlated with…

Children with autism experience difficulties in understanding social affective cues, and it has been suggested that such deficits will generalize to music. In order to investigate this proposal, typically developing individuals and children with autism and Down syndrome were compared on tasks measuring perception of affective and movement states…