The Heart of Embodied Morality: Investigating the Role of the Evolved Developmental Niche on Autonomic Regulation

Optimal social and moral capacities are dependent upon healthy neurobiological functioning.Both require autonomic regulation that involves the capacity to regulate stress coupled with the ability to adapt to changing contexts.Converging evidence from numerous fields demonstrates that the neurobiological underpinnings of these behaviors are shaped by early experience and the caregiving environment.Extensive neurobiological immaturity in childhood results in malleability to environmental influences, especially in the first year of life, with neurobiological alterations that often persist into adulthood, influencing social and moral capacities.

In order to examine the influence of early experience on autonomic regulation, a longitudinal study was conducted with mothers and their children: early life experience was assessed at 12 months according to consistency with the evolved developmental niche (EDN), the ecological system of care evolved to foster human health. Respiratory sinus arrhythmia (RSA; vagal functioning) for both members of the dyad was assessed five years later.RSA was measured across three conditions: baseline, stress and recovery.RSA is a transdiagnostic biomarker for emotional regulation, psychopathology, social adaptability and is an online metric of parasympathetic functioning.Due to its wide influence in numerous social and moral behaviors, RSA was utilized as an online biomarker for healthy neurobiological functioning, examining both tonic vagal tone and flexibility of vagal functioning.Few studies have examined vagal flexibility, especially in the context of examining the influence of early experience.

For mothers, latent growth curve models demonstrated that childhood history of positive home climate predicted higher mean levels of RSA across all conditions whereas childhood social embeddedness predicted both tonic and flexible parasympathetic regulation.For children, harsh touch at 12 months predicted lower levels of vagal functioning across all conditions, suggesting a more stressed tonic level of general functioning.In this way, aspects of EDN-consistent experience predicted both tonic and flexible vagal functioning later in life.The results support the notion that provision of the EDN in childhood may promote overall parasympathetic functioning and autonomic flexibility, supporting the neurobiological architecture needed for healthy social and moral behaviors.