Contributions of infant vagal regulation at 1 month to subsequent joint attention abilities.

Since birth, humans develop an ability to regulate their inner states and behaviors, when facing demanding situations, in order to restore calmness and engage with other persons and the surrounding environment. The present study analyzed whether 1-month infant vagal regulation to auditory stimuli was associated with later joint attention abilities-responding to and initiating joint attention-in interaction with their mothers. Twenty-three infants were assessed and measures of respiratory sinus arrhythmia-RSA (baseline and vagal tone change during auditory stimulation) were used as index of vagal regulation. At 12-months, joint attention behaviors were assessed in a 10-min toy-play mother-infant interaction. Correlational analyses showed that lower baseline RSA and larger increases in vagal tone during auditory stimulation were related to more instances of joint attention behaviors at 12 months, especially responding to joint attention. Results suggest that distinct profiles of autonomic functioning may contribute to joint attention skills.