At the Interface Between Parasympathetic Activity and Self‐Regulation in Young Children: Introduction to the Special Issue

The parasympathetic nervous system (PNS) is highly responsive to changes in environmental conditions and serves an essential role in mobilising the metabolic resources required for young children to regulate their thoughts, emotions and behaviours. According to polyvagal theory, the PNS evolved to play a leading role in the neurophysiological response to situations that range from modestly challenging to engaging, and many situations in which young children must exercise volitional processes of self‐regulation conform to this description. Children's phasic parasympathetic activity during measures of volitional self‐regulation is often associated with their performance on those measures or with their performance on other assessments of self‐regulation, but the nature of the associations between PNS activity and performance on measures of volitional self‐regulation is highly variable. This heterogeneity complicates the interpretation of results obtained across different studies and inhibits our ability to formulate directional hypotheses about what patterns of phasic parasympathetic activity we would expect to observe as young children exercise volitional processes of self‐regulation in different situations. This special issue presents a set of papers that addressed these challenges by administering multiple measures of volitional self‐regulation to the same sample of children or by examining how children's characteristics and experience in their developmental environments may account for observed differences in their phasic PNS activity.