We describe the development of 236 children with Angelman syndrome (AS) using the Bayley Scales of Infant and Toddler Development, Third Edition. Multilevel linear mixed modeling approaches were used to explore differences between molecular subtypes and over time. Individuals with AS continue to make slow gains in development through at least age…

This study examined whether parent-reported atypical development in their child's first year was associated with age of diagnosis and age when parents first needed to consult a specialist about their child's development. It involved 423 children who participated in the Australian Autism Biobank. Most parents retrospectively identified [greater or…

New motor skills can shape how infants communicate with their caregivers. For example, learning to walk allows infants to move faster and farther than they previously could, in turn allowing them to approach their caregivers more frequently to gesture or vocalize. Does the link between walking and communication differ for infants later diagnosed…

CDKL5 deficiency disorder (CDD) results in early-onset epilepsy and lifelong cognitive and motor impairments. With no validated measure for communication in CDD, this study evaluated the psychometric properties of the Communication and Symbolic Behavior Scales-Developmental Profile Infant Toddler Checklist (CSBS-DP ITC). Caregivers (n = 150;…

A growing literature supports the feasibility and validity of telehealth-based assessments for autism spectrum disorder (ASD). Better understanding families' experiences is crucial for sustained use beyond the COVID-19 pandemic. This study qualitatively examines caregiver experiences with the Telehealth Evaluation of Development for Infants (TEDI)…

Parents participating in a prospective longitudinal study of infants with older siblings with autism completed an autism screening questionnaire and were asked about any concerns relating to their child's development, and children were administered an interactive assessment conducted by a researcher at 14 months. Scores on the parent questionnaire…

Research indicates that individuals with autism spectrum disorder (ASD) are superior at local processing while the integration of local features to global percepts is reduced. Here, we compared infants at familiar risk for ASD to typically developing infants in terms of global coherence processing at 5 months of age, using steady state visually…

This study investigated early posture development prospectively in infants at heightened (HR) vs. low risk (Low Risk; LR) for ASD. Fourteen HR infants diagnosed with ASD (HR-ASD), 17 HR infants with language delay (HR-LD), 29 HR infants with no diagnosis (HR-ND), and 25 LR infants were videotaped at home for 25 min during everyday activities and…

Infants show shifting patterns of visual engagement to faces over the first years of life. To explore the adaptive implications of this engagement, we collected eye-tracking measures on cross-sectional samples of 10-25-month-old typically developing toddlers (TD;N = 28) and those with autism spectrum disorder (ASD;N = 54). Concurrent language…

We delineate the sequence that typically developing infants pass tasks that assess different early social cognitive skills considered precursors to theory-of-mind abilities. We compared this normative sequence to performance on these tasks in a group of autistic (AUT) children. 86 infants were administered seven tasks assessing "intention…

Specific developmental concerns can distinguish between an early versus later diagnosis of autism spectrum disorder (ASD). Caregiver survey responses of children = 9 years-of-age (2012) with ASD were used to evaluate developmental concerns and associations with age of diagnosis [early (< 3 years: n = 106) vs. later (= 3 years: n = 432)] using…

This study examines whether parental report of social-communicative and repetitive behaviors at 12 months can be helpful in identifying autism spectrum disorder (ASD) in younger siblings of children with ASD [high-risk (HR)-siblings]. Parents of HR-siblings and infants without a family history of ASD completed the First Year Inventory at…

This study examined the developmental profile of male infants with fragile X syndrome (FXS) and its divergence from typical development and development of infants at high risk for autism associated with familial recurrence (ASIBs). Participants included 174 boys ranging in age from 5 to 28 months. Cross-sectional profiles on the Mullen Scales of…

An emerging focus of research on autism spectrum disorder (ASD) targets the identification of early-developing ASD endophenotypes using infant siblings of affected children. One potential neural endophenotype is resting frontal electroencephalogram (EEG) alpha asymmetry, a metric of hemispheric organization. Here, we examined the development of…

Thyroid hormones are critical for normal brain development. This study examined autism spectrum disorders (ASD) and thyroid stimulating hormone (TSH) levels measured in mid-pregnancy maternal serum and infant blood after birth. Three groups of children born in Orange County, CA in 2000-2001 were identified: ASD (n = 78), developmental delay…