Shared Positive Affect: An Early Behavioral Risk Marker for Autism Spectrum Disorders?

Abstract

PSYCHOLOGY

SHARED POSITIVE AFFECT: AN EARLY BEHAVIORAL RISK MARKER FOR AUTISM SPECTRUM DISORDERS?

CAITLIN R. MCMAHON

Dissertation under the direction of Professor Wendy L. Stone This project examined the early social-emotional behavior of shared positive affect and its component behaviors (i.e., eye contact and smiling) in a sample of younger at-risk siblings of children with autism (Sibs-ASD) and a comparison group of younger siblings of typically developing children (Sibs-TD). In this dissertation I compare the groups on the frequency and duration of these behaviors as well as comparing these behaviors to outcome measures of autism symptomatology. This research showed that Sibs-TD, on average, demonstrate more frequent occurrences and longer duration episodes of positive affect, and specifically shared positive affect, than Sibs-TD. No differences emerged between the groups on measures of social attention (i.e., eye contact). The predictive validity of the coded measure of shared positive affect was supported by its significant negative correlations with multiple measures of autism symptomatology at follow-up. The implications for considering shared positive affect as an early behavioral risk marker in early screening for autism spectrum disorders are discussed.