The block design task (BDT) is a visuospatial measure that individuals with Williams syndrome (WS) perform poorly on. However, it is unclear what underlies their impaired performance. This study investigated whether poorer performance is a result of visuospatial difficulties, executive function (EF) difficulties, atypical looking strategies, or a…

The phonological awareness skills of 7- to 8-year-old children with intellectual disability (ID) were compared to those of 4- to 5-year-old typically developing children who were matched for early reading skills, vocabulary, and gender. Globally, children with ID displayed a marked weakness in phonological awareness. Syllable blending, syllable…

On average, adults with intellectual disability (ID) have higher mortality risk than their peers in the general population. However, the effect of age on this mortality disadvantage has received minimal attention. Using data from the 1986-2011 National Health Interview Survey-Linked Mortality Files (NHIS-LMF), discrete time hazard models were used…

This study compares characteristics and outcomes of 70 defendants with and 1,122 without intellectual and developmental disabilities (IDD) participating in a mental health court. Demographic and clinical characteristics differed, but criminal justice or program characteristics did not. Age, race, marital status, living situation, court location,…

A number of studies suggest that imitation is a characteristic strength in children with Down Syndrome (DS). The present study aims to discover whether imitation performances are qualitatively phenotypical in DS. Eight preschoolers with DS were matched on chronological, mental, language and imitation age with 8 preschoolers with intellectual…

A review of hospital records was conducted for children evaluated for autism spectrum disorders who completed both the Leiter International Performance Scale-Revised (Leiter-R) and Stanford-Binet Intelligence Scales, 5th Edition (SB5). Participants were between 3 and 12 years of age. Diagnoses were autistic disorder (n = 26, 55%) and pervasive…

Studies of individuals with Cornelia de Lange syndrome (CdLS) have described changes in mood and behavior with age, although no empirical or longitudinal studies have been conducted. Caregivers of individuals with CdLS (N = 67), cri du chat syndrome (CdCS; N = 42), and Fragile X syndrome (FXS; N = 142) completed the Mood, Interest and Pleasure…

Anxiety is among the most impairing conditions associated with Fragile X syndrome (FXS) and is putatively linked to atypical physiological arousal. However, few studies have examined this association in young children with FXS. The authors examined whether patterns of arousal and behavior during an experimental stranger approach paradigm differ…

Dyads of siblings in which the younger sibling had an intellectual disability (ID, n = 25) were videotaped interacting. The ID group was compared with typically developing sibling dyads matched on mental age (n = 25) and chronological age (n = 25). We observed the mediation strategies, activation, and antimediation behaviors of older siblings and…

Using population data, this study included parents of individuals with intellectual and developmental disabilities (n = 220) and parents of individuals without disabilities (n = 1,042). Parents of individuals with intellectual and developmental disabilities were further divided into those who co-resided with their adult child and those whose adult…

The current study prospectively examined trajectories of change in symptoms of irritability, hyperactivity, and social withdrawal, as well as predictors of such behaviors, for ages 9-18 years for youths with autism spectrum disorder and a comparison group with nonspectrum developmental delays. Children with more severe core features of autism had…

We examined auditory perception in Williams syndrome by investigating strategies used in organizing sound patterns into coherent units. In Experiment 1, we investigated the streaming of sound sequences into perceptual units, on the basis of pitch cues, in a group of children and adults with Williams syndrome compared to typical controls. We showed…

A functional polymorphism in the promoter of the gene encoding monoamine oxidase A has been associated with problem behavior in various populations. We examined the association of MAOA alleles in adult males with intellectual/developmental disabilities with and without established histories of problem behavior. These data were compared with a…

The "Down syndrome advantage" is the popular conception that children with Down syndrome are easier to rear than children with other developmental disabilities. We assessed whether mothers of children with developmental disabilities would demonstrate a consistent Down syndrome advantage as their children aged from 12 to 18 years. Results did not…