The social and motor context in which restricted and repetitive behaviors (RRBs) occur in autism and their relationship to social traits are not well-understood. Participants with and without autism completed tasks that varied in social and motor engagement and RRB frequency was measured. Motor and verbal RRBs were most common, RRBs varied based…

Background: Children and adults with neurotypical development employ linguistic information to predict and anticipate information. Individuals with Down syndrome (DS) have weaknesses in language production and the domain of grammar but relative strengths in language comprehension and the domain of semantics. What is not clear is the extent to…

It has been reported that approximate number sense (ANS) task performance is impaired in individuals with Williams syndrome (WS) and Down syndrome (DS). Research with infants has suggested this impairment is caused by sticky fixation in WS and sustained attention deficits for those with DS. This study examined looking patterns of older children…

Purpose: Many observations and anecdotes have suggested that individuals with Down syndrome (DS) love music, specifically moving to music. The purpose of this study, with the assumption that the music makes people with DS dance showing more movement than general public's, is to observe the change in movement patterns of people with DS while they…

Children often answer questions when they do not have the requisite knowledge or when they do not understand them. We examined whether "ground rules" instruction--to say "I don't know," to tell the truth, and to correct the interviewer when necessary--assisted children in applying those rules during an interview about a past…

General cognitive and specific number abilities that underlay arithmetic performance have been heavily investigated among typically developing students; however, the inquiry has rarely been applied to students with mild intellectual disability (MID). We examined whether domain-general cognitive abilities (i.e. working memory, processing speed, and…

We investigate the function bias--generalising words to objects with the same function--in typically developing (TD) children, children with autism spectrum disorder (ASD) and children with other developmental disorders. Across four trials, a novel object was named and its function was described and demonstrated. Children then selected the other…

Here we examine imaginative drawing abilities in children with Autism Spectrum Disorder (ASD) and learning disabilities (LD) under several conditions: spontaneous production, with use of a template, and combining two real entities to form an "unreal" entity. Sixteen children in each group, matched on mental and chronological age, were…

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…

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,…

Children with autism spectrum disorders (ASDs) routinely fail false belief tests of theory of mind (ToM), even at advanced chronological and mental ages. Initial training efforts were largely disappointing for those with ASD, suggesting an intractable deficit. However, more recently, children with ASD trained with various pictorial strategies…

Objective: To examine the ability of children with intellectual disabilities to give reliable accounts of personally experienced events, considering the effects of delay, severity of disability, and the types of interview prompt used. Method: In a between-subjects design, we compared children with intellectual disabilities (7-12 years) that fell…

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…

Differences in joint attention are prominent for some children with autism and are often used as an indicator of the disorder. This study examined the joint attention competencies of young children with autism who demonstrated joint attention ability and compared them to children with developmental delays. A total of 40 children with autism and…

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…