Autonomic nervous system functioning in early childhood: responses to laboratory challenges, individual differences, and relations to child self-regulation

The goals of this study were (a) to examine children’s normative sympathetic and parasympathetic autonomic nervous system (ANS) responses toward distinct emotional and cognitive laboratory challenges from preschool to grade 1 and to compare the magnitude of ANS responses across these challenges, (b) to examine the associations between sympathetic and parasympathetic ANS responses during laboratory challenges, (c) to examine stability (or instability) and continuity (or change) in ANS functioning from preschool to grade 1, and (d) to examine profiles of children with distinct patterns of sympathetic and parasympathetic functioning in preschool, and to test whether these profiles differ with respect to children’s self-regulation outcomes in preschool and one year later. Two hundred and seventy-eight children and their caregivers (96% mothers) participated in laboratory assessments when children were in preschool, kindergarten, and first grade, and teachers reported on children’s behavior when children were in kindergarten. Children’s sympathetic and parasympathetic ANS responses were measured during 2 emotionally demanding and 2 cognitively demanding laboratory challenges in preschool, kindergarten, and first grade. Three self-regulation outcomes were assessed: (a) executive functioning, (b) emotional reactivity/regulation, and (c) behavioral regulation in the classroom. In preschool, executive functioning was measured using 3 tasks designed to assess working memory, inhibitory control, and cognitive flexibility; emotion regulation was observed during frustrating challenges; and mothers reported on children’s emotional reactivity. In kindergarten, teachers reported on children’s emotional reactivity and behavioral regulation composed of attention control, discipline/persistence, and work habits in the classroom. Although children, on average, demonstrated parasympathetic inhibition (RSA withdrawal) across all challenges, they showed sympathetic responsivity only during certain challenges. In particular, the cognitively demanding problem-solving Tangrams task, on average, elicited sympathetic activation (PEP shortening) across all time points, whereas the less challenging Go/No-Go task, did not lead to a change in sympathetic activity in preschool or kindergarten but led to sympathetic activation in grade 1. Four blocked-goal frustration tasks (Locked Box, Impossible to Open Gift, Puzzle Box, & Broken Toy) did not lead to a change in sympathetic ANS activity from baseline to task, whereas the two interpersonally upsetting tasks (Toy Removal and Not Sharing) led to sympathetic inhibition (PEP lengthening). There was a positive association between sympathetic and parasympathetic responsivity during only certain challenges (e.g., Tangrams & Locked Box in preschool, Not Sharing & Impossible to Open Gift in kindergarten), such that greater sympathetic activation was associated with greater parasympathetic withdrawal. There was moderate stability in ANS children’s responsivity across different tasks within the same assessment. There was modest stability in parasympathetic ANS responses but no stability in sympathetic responses toward laboratory challenges across time. In regards to developmental continuity/change, both baseline sympathetic and parasympathetic ANS activity increased from preschool to first grade. However, there was no clear pattern of change in children’s ANS responsivity toward the cognitively demanding laboratory challenges over time, suggesting that mean level ANS responsivity scores were mostly continuous over time. Finally, the latent profile analyses yielded four profiles of ANS functioning: (a) a buffered profile with moderate ANS responsivity, (b) a sensitive profile with high ANS responsivity, (c) a coinhibition profile, and (d) a vigilant profile. Children in the sensitive profile demonstrated better executive functioning than children in the buffered and the vigilant groups. The buffered profile showed lower levels of emotional reactivity than the sensitive profile, and better behavioral regulation than the sensitive, coinhibition, and vigilant groups. Profiles did not differ with respect to mothers’ report of emotional reactivity or observed emotion regulation