Developmental patterns of respiratory sinus arrhythmia from toddlerhood to adolescence.

Parasympathetic nervous system functioning as indexed by respiratory sinus arrhythmia (RSA) is widely used as a measure of physiological regulation. We examined developmental patterns of children's resting RSA and RSA reactivity from 2 to 15 years of age, a period of time that is marked by considerable advances in children's regulatory abilities. Physiological data were collected from a community sample of 270 children (116 males) during a...