Purpose: Gesture delay in autistic infants and toddlers has been widely reported. The developmental trajectory of gesture production during early childhood is understudied. Thus, little is known about the possible changes of gesture production over time. The present study aimed to document the development of gesture production in autistic children…

Studies have shown that there are differences between the presentations of males and females diagnosed with autism. There remains a developing understanding about how the presentation of autism differs between boys (hereafter referred to as 'assigned males at birth') and girls (assigned females at birth). This study sought to investigate the…

Robust evidence supports the efficacy of early autism intervention. Despite broad consensus that earlier intervention leads to better outcomes, evidence for this has been limited to correlational studies. This study examined timing effects of the Early Social Interaction (ESI) model, a parent-implemented intervention, using a complete crossover…

Feasible and accurate assessment tools developed for non-specialists are needed to scale community-based models of autism evaluation. The purpose of this study was to evaluate use of the Screening Tool for Autism in Toddlers and Young Children (STAT) when used by primary care practitioners (n = 10) across a statewide system of early diagnosis set…

Autism is often associated with early developmental delays in language and motor skills. However, little is known about the complex dynamic processes that drive the co-development of such early difficulties. The aim of the present study was to model the parallel growth of language and motor skills in a cohort of infants and to explore differences…

Purpose: The study explored longitudinally the course of vocabulary and general language development in a group of infants with Down syndrome (DS) compared to a group of typically developing (TD) infants matched on nonverbal mental ability (NVMA). Method: We compared the vocabulary and general language trajectories of the two groups in two ways:…

Inconsistent findings regarding sex differences in cognition have been found in people with autism spectrum disorder (ASD). This study evaluated sex differences in cognitive-developmental functioning in a large clinical sample of young children diagnosed with ASD. The sample included children 18-68 months of age who received the Mullen Scales of…

It is well established that deictic gestures, especially pointing, play an important role in children's language development. However, recent evidence suggests that other types of deictic gestures, specifically show and give gestures, emerge before pointing and are associated with later pointing. In the present study, we examined the development…

Background and Aims: The purpose of this exploratory study was to expand existing literature on prelinguistic vocalizations by reporting results of the first home-based longitudinal study examining a wide variety of behaviors and characteristics, including early vocalizations, across infants at low and elevated risk of autism spectrum disorder…

This study explores the cognitive development of children born to adolescent mothers within South Africa compared to existing reference data, and explores development by child age bands to examine relative levels of development. Cross-sectional analyses present data from 954 adolescents (10-19 years) and their first-born children (0-68 months).…

There is a critical need for validated screening tools for autism spectrum disorder in very young children so families can access tailored intervention services as early as possible. Few screeners exist for children between the recommended screening ages of 18-24 months. This study examined the utility of a new autism-specific parent-report…

Atypical motor development has frequently been reported in infants at elevated likelihood for autism spectrum disorder. However, no previous study has used detailed motion capture technology to compare infant siblings of children with autism spectrum disorder and infant siblings with no familial history of autism spectrum disorder. We investigated…

Autism spectrum disorder symptom emergence is heterogeneous, yet literature comparing young children diagnosed early versus later is relatively scant. Toddlers diagnosed with autism spectrum disorder between 12 and 18 months (n = 20), 19 and 24 months (n = 65), or 25 and 41 months (n = 27) were compared on demographics, developmental functioning,…

Purpose: Differences in communication development impact long-term outcomes of children with autism. Previous research has identified factors associated with communication in children with autism, but much of the variance in communication skill remains unexplained. It has been proposed that early differences in sensory responsiveness (i.e.,…

We examined differences between children with autism spectrum disorder and typically developing children over an 8-month period in: (a) longitudinal associations between expressive and receptive vocabulary and (b) the extent to which caregiver utterances provided within an "optimal" engagement state mediated the pathway from early…