Background: While delays in cognitive development are detectable during early development in Down syndrome, the neuropsychological and biomedical underpinnings of cognitive skill acquisition in this population remain poorly understood. Method: To explore this issue, 38 infants with Down syndrome [mean chronological age = 9.65 months; SD = 3.64]…

Background: Several studies show that socio-economic status (SES) is related to the developmental trajectories of children with typical development (TD). However, few studies have analysed this relationship regarding children with neurodevelopmental disorders such as Down syndrome (DS). In this paper, we analyse the impact of SES in the…

Background: Sleep affects children's cognitive development, preparedness for school and future academic outcomes. People with Down syndrome (DS) are particularly at risk for sleep-disordered breathing (SDB). To our knowledge, the association between SDB and cognition in preschoolers with DS is unknown. Methods: We assessed sleep by using…

Background: Despite an increase in international studies examining the experiences of parents with intellectual impairments and their children, few have utilised population-based data. This study investigated the behavioural and cognitive outcomes of 3-year-old US children of mothers with intellectual impairments compared with children of mothers…

Background: Individuals with Williams syndrome (WS) show difficulties in attributing false beliefs, whereas they are better at attributing emotions. This study examines whether being asked about the emotion linked to a false belief, instead of explicitly about the belief, facilitates performance on theory of mind (ToM) tasks. Method: Thirty…

Background: Impairment in initiating joint attention (IJA) is associated with autism spectrum disorder (ASD) in children, although it is unclear when impairments arise. Due to the early development of IJA use and late diagnosis of ASD, groups at high-risk of ASD, such as infants with an older sibling with ASD (ASIBs) and infants with fragile X…

Background: Individuals with fragile-X syndrome exhibit developmental delay, hyperexcitation and social anxiety; they also show lack of attention and hyperactivity. Few studies have investigated whether levels of functioning change with increasing age. Here, we explored developmental changes across adolescence in the cognitive and behavioural…

Background: Williams syndrome (WS) is associated with a distinct cognitive-behavioural phenotype including mild to moderate intellectual disability, visual-spatial deficits, hypersociability, inattention and anxiety. Researchers typically characterise samples of individuals with WS by their intellectual functioning and adaptive behaviour. Because…

Background: There is conjecture regarding the profile of cognitive development over time in children with Down syndrome (DS). Characterising this profile would be valuable for the planning and assessment of intervention studies. Method: A systematic search of the literature from 1990 to the present was conducted to identify longitudinal data on…

Background: Individuals with Williams syndrome (WS) show a disharmonic linguistic profile with a clear pattern of strengths and weaknesses. Despite their sociable nature, atypical socio-communicative abilities and deficits in communication and relationship with others have been found. Aim: The aim of the present study was to investigate whether…

Background: Girls with fragile X syndrome (FXS) have a wide range of cognitive and language abilities. The range of language outcomes experienced by girls with FXS, however, has been relatively unexplored. The purpose of this exploratory study was to examine receptive and expressive language, with a focus on vocabulary and syntax, in a group of…

Background: Marshall-Smith syndrome (MSS) is an infrequently described entity characterised by failure to thrive, developmental delay, abnormal bone maturation and a characteristic face. In studying the physical features of a group of patients, we noticed unusual behavioural traits. This urged us to study cognition, behavioural phenotype and…

Characterising how socio-cognitive abilities develop has been crucial to understanding the wider development of typically developing children. It is equally central to understanding developmental pathways in children with intellectual disabilities such as Down's syndrome. While the process of acquisition of socio-cognitive abilities in typical…

Background: It has been suggested that children with intellectual disabilities (ID) have motor problems and higher-order cognitive deficits. The aim of this study was to examine the motor skills and executive functions in school-age children with borderline and mild ID. The second aim was to investigate the relationship between the two performance…

Background: The present study was aimed at investigating working memory (WM) and executive functions capacities in individuals with Williams syndrome (WS) as compared with mental-age matched typically developing (TD) children. Method: In order to serve the study goal, a sizeable battery of tasks tapping WM as well as attention, memory, planning,…