Cognition Research Today is a free monthly online journal that collates and summarizes the latest research about Cognition, including details on psychology, neuroscience, memory, brain theory.

Early social-communicative and cognitive development of younger siblings of children with autism spectrum disorders.

Stone WL, McMahon CR, Yoder PJ, Walden TA

Kennedy Center, Department of Pediatrics, Vanderbilt University, Nashville, TN 37203, USA. wendy.stone@vanderbilt.edu

OBJECTIVE: To compare the early social-communicative development of younger siblings of children with autism spectrum disorders (ASDs) with that of younger siblings of children with typical development, using parental report and child-based measures. DESIGN: Group comparison. SETTING: Vanderbilt University, between July 1, 2003, and July 31, 2006. PARTICIPANTS: Younger siblings of children with ASD (n = 64) and younger siblings of children with typical development (n = 42) between the ages of 12 and 23 months (mean, 16 months). Main Exposure Having a sibling with an ASD. OUTCOME MEASURES: Child-based measures included a cognitive assessment; an interactive screening tool assessing play, imitation, and communication; and a rating of autism symptoms. Parental report measures were an interview of social-communicative interactions and a questionnaire assessing language and communication skills. RESULTS: Younger siblings of children with ASD demonstrated weaker performance in nonverbal problem solving (mean difference [MD], 5.91; 95% confidence interval [CI], 2.48-9.34), directing attention (MD, 0.52; 95% CI, 0.07-0.97), understanding words (MD, 33.30; 95% CI, 3.11-63.48), understanding phrases (MD, 4.56; 95% CI, 1.85-7.27), gesture use (MD, 1.49; 95% CI, 0.51-2.47), and social-communicative interactions with parents (MD, 1.32; 95% CI, 0.27-2.37), and had increased autism symptoms (MD, 2.54; 95% CI, 1.05-4.03), relative to control siblings. A substantial minority of the ASD sibling group exhibited lower performance relative to controls. Significant correlations between child-based measures and parental reports assessing similar constructs were found (r = -0.74 to 0.53; P range, .000-.002). CONCLUSION: The weaker performance found for children in the ASD sibling group may represent early-emerging features of the broader autism phenotype, thus highlighting the importance of developmental surveillance for younger siblings.

Published 3 April 2007 in Arch Pediatr Adolesc Med, 161(4): 384-90.
Full-text of this article is available online (may require subscription).

© 2005-2008 Cognition Research Today. All Rights Reserved.