Developmental trajectories of respiratory sinus arrhythmia: Associations with social responsiveness

Abstract

The present longitudinal study examined relations between respiratory sinus arrhythmia (RSA) development and social responsiveness characteristics associated with autism spectrum disorders. Group‐based developmental trajectory modeling was used to characterize RSA development patterns in 106 typically developing children across 5, 10, 24, 36, and 48 months of age. A two‐group model fit of RSA development was found: a “typically” and “atypically” developing group. The typical group gradually increased in RSA across 5–48 months of age. The atypical group, however, increased in RSA from 5 to 24 months and demonstrated a plateau or “delay” in RSA development from 24 to 48 months. The atypical RSA development group also demonstrated more difficulties in parent‐reported social responsiveness at 48 months. The results support current literature that identifies RSA as a marker of social functioning level. © 2013 Wiley Periodicals, Inc. Dev Psychobiol 56: 317–326, 2014.