Relations Between Hypothalamic-Pituitary-Adrenal Axis and Autonomic Nervous System Activity and Children’s Executive Functions in Environments of Early-life Stress
Stephen Braren1, Annie Brandes-Aitken1, Clancy Blair1; 1New York University
Exposure to early-life environments of stress can influence the development and functioning of cognitive processes such as executive functions (EF). The relation between EF and stress has been associated with both hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system (ANS) activity, although most related research has not examined these two physiological systems in tandem. In the current study, we used data from a large, longitudinal sample (N=1292) of low-income children to investigate concurrent functioning of HPA axis and ANS activity in relation to EF. Children were seen in their homes at 48 and 58 months of age and participated in a battery of EF tasks. At 48 months, three child saliva samples were collected and assayed for cortisol, and electrocardiography was recorded before (baseline) and during (reactivity) the EF tasks to measure respiratory sinus arrhythmia (RSA) and inter-beat interval (IBI). Results revealed that baseline cortisol levels were positively associated with working memory and inhibitory control at 48 months. At 58 months, baseline RSA was negatively associated with inhibitory control and baseline IBI was negatively related to working memory. IBI reactivity was positively associated with working memory at 48 and 58 months and attention shifting at 58 months. Conversely, RSA reactivity was negatively associated with working memory at both ages and attention shifting at 58 months. These results provide insight into how ANS and HPA axis activity differentially relate to children’s EF, and point to possible mechanisms of risk and resilience in contexts of adversity that warrant further investigation.
Topic Area: EXECUTIVE PROCESSES: Working memory