Few studies have examined differences in autism spectrum disorder (ASD) phenotype between children from multiplex and simplex families at the time of diagnosis. The present study used an age- and gender-matched, community-based sample (n = 105) from the southwestern United States to examine differences in ASD symptom severity, cognitive…

While advances in intensive neonatal care have greatly improved survival rates among preterm infants, incidence of neurodevelopmental disorders in this group is still high, with autism spectrum disorder (ASD) being one of the most frequent. To this end, we conducted a social-communication intervention aimed at investigating efficacy in…

Studies are needed to better understand the broad autism phenotype in young siblings of children with autism. Cognitive, adaptive, social, imitation, play, and language abilities were examined in 42 non-autistic siblings and 20 toddlers with no family history of autism, ages 18-27 months. Siblings, as a group, were below average in expressive…

Cognitive and language skills of 39 siblings of children with autism (SIBS-A) and 39 siblings of typically developing children (SIBS-TD) at ages 4, 14, 24, 36, and 54 months were compared. Twelve of the 39 SIBS-A revealed a delay in cognition and/or language (including one child diagnosed with autism) compared to only two SIBS-TD. Developmental…

This paper reports on the developmental progression of a sample of 48 adolescents and young adults with autism who were previously assessed at preschool age and again in the mid-school period. In contrast to the earlier period when about one-third of the children made dramatic gains, cognitive and language skills tended to remain stable or decline…