Phelan-McDermid syndrome (PMS), caused by "SHANK3" haploinsufficiency, lacks natural history data. We report the trajectory of adaptive behavior from a prospective, longitudinal, natural history study. English-speaking people aged 3-21 years with a PMS molecular diagnosis were followed over 2 years. We analyzed longitudinal Vineland…

This study investigated the bidirectional effects of change in maladaptive behaviors among adolescents and adults with fragile X syndrome (FXS) and change in their intergenerational family relationships over a 7.5-year period. Indicators of the intergenerational family relationship between premutation carrier mothers and their adolescent or adult…

Objective: This study aimed to investigate the relationship between Cognitive Disengagement Syndrome (CDS) symptoms in children/adolescents and their parents within the Turkish population, examining the association with co-occurring ADHD symptoms, peer/social relationships, and total difficulties. Method: The study included 229 parents aged 18 to…

In this study, we examined trajectories of specific domains of behavior problems (i.e., attention problems, depression/anxiety, and aggressive behavior) from age 6 to 18 in a sample of 55 children with fragile X syndrome. We also examined autism status and early parenting as predictors of subsequent behavioral trajectories. We found that attention…

Klinefelter syndrome (47,XXY) is associated with problems in social interaction and behavioral adaptation. Sixteen adolescents and adult men with 47,XXY enrolled in a pilot-study evaluating the effectiveness of Social Management Training (SMT), a novel neurocognitive-behavioral treatment program targeted at improving social, emotional, and…

This study examined trajectories of daily living skills, behavior problems, body mass index (BMI), and health conditions spanning nearly a decade in adolescents and adults with fragile X syndrome (N = 134; age range at study end = 19-49 years), examining influences of sex and autism spectrum disorder (ASD) symptoms. Hierarchical linear modeling…

School psychologists are asked to provide a number of different services in schools, including evaluating and providing recommendations to educators and parents on children and adolescents with rare genetic conditions. One genetic disorder with physical, cognitive, and behavioral features is Prader-Willi syndrome (PWS). PWS is a unique genetic…

Purpose: Pragmatic language skills are often impaired above and beyond general language delays in individuals with neurodevelopmental disabilities. This study used a multimethod approach to language sample analysis to characterize syndrome- and sex-specific profiles across different neurodevelopmental disabilities and to examine the congruency of…

The present investigation explored long-term relationships of behavioral symptoms of adolescents and adults with developmental disabilities with the mental health of their mothers. Fragile X premutation carrier mothers of an adolescent or adult child with fragile X syndrome (n = 95), and mothers of a grown child with autism (n = 213) were…

Many males with FXS meet criteria for ASD. This study was designed to (1) describe ASD symptoms in adolescent and young adult males with FXS (n = 44) and (2) evaluate the contributions to ASD severity of cognitive, language, and psychiatric factors, as well as FMRP (the protein deficient in FXS). A few ASD symptoms on the ADOS-2 were universal in…

Literature on the level of adaptive functioning and relative strengths and weaknesses in functioning of individuals with Williams syndrome (WS) was reviewed. The electronic databases PsycINFO, PubMed, Expanded Academic, Web of Science, Scopus and ProQuest were searched electronically for relevant articles and dissertations using the search terms…

The primary objectives of the current prospective longitudinal study were to (a) describe social functioning outcomes and (b) identify childhood predictors of social functioning in young adults with (22q11.2DS). Childhood predictors of young adult social functioning were examined. Family environment and parental stress in adolescence were…

Problem behavior of 52 children with Williams syndrome ages 6 to 17 years old was examined based on both parent and teacher report. Generally good inter-rater agreement was found. Common areas of problem behavior based both on parent and teacher report included attention problems, anxiety difficulties, repetitive behaviors (e.g., obsessions,…

The present study examined trajectories of adaptive behavior, behavior problems, psychological symptoms, and autism symptoms in adolescents and adults with fragile X syndrome (n = 147) over a three-year period. Adaptive behavior significantly increased over time, particularly for adolescents, and the severity of behavior problems decreased over…

Few published studies have reported on the psychological well-being of family members of individuals with Rett syndrome (RTT). Eighty-seven mothers of girls and women with RTT completed a questionnaire survey about their daughters' behavioral phenotype, current health, and behavior problems, and their own and a sibling's well-being. Mothers…