Multisystem Stress Activity in Early Childhood Aggression and Callous-Unemotional Behaviors.

• In Event: Multisystem Stress Activity and Subtypes of Aggression in Three Developmental Periods.

Abstract

Both the sympathetic nervous system (SNS) and hypothalamic-pituitary-adrenal axis (HPA axis) have been implicated in the development of externalizing problems, with higher levels thought to represent risk for emotionally-driven behaviors and lower levels thought to represent callous behavior (e.g., Hagan et al., 2020). Considering the coordination between these systems may provide unique information, as the SNS and HPA-axis involve semi-independent, but potentially complementary, processes in responses to stress and threat (Koss & Gunnar, 2018). The Adaptive Calibration Model (ACM; Del Giudice et al., 2011) suggests that individuals with a vigilant profile (i.e., high SNS and HPA-axis activity) are prone to engage in reactive aggression and impulsivity, whereas those with an unemotional profile (i.e., low SNS and HPA-axis activity) demonstrate callous-unemotional (CU) behaviors. Prior work in early childhood on these profiles predicting externalizing behavior is mixed (Hagan et al., 2020), and no studies have tested the role of the unemotional profile with CU behaviors in early childhood. This study tests associations between basal SNS and HPA-axis activity (measured using salivary cortisol and α-amylase [sAA], respectively) and their interaction with forms of aggression and CU behaviors in early childhood. We expected the unemotional profile to be associated with CU behaviors, and the vigilant profile to be associated with physical and relational aggression (which likely represent reactive behavior with CU behaviors controlled).

The sample consists of 201 preschoolers (Mage = 51.71 months, SD = 3.72 months, 47.8% female) from an ongoing longitudinal study. Measures were collected during the fall of participants’ pre-kindergarten year. Saliva was collected across three consecutive days in the morning at home or school depending on Covid-19 restrictions, and samples were averaged to create indexes of basal sAA and cortisol. Cortisol and sAA levels were highly internally consistent across the three collection days (Cronbach αs = .76 - .85). CU behaviors were measured using parent report on the Inventory of Callous-Unemotional traits (Frick, 2004). Physical and relational aggression were measured using teacher report on the Preschool Social Behavior Scale (Crick et al., 1997). All measures were internally consistent (Cronbach αs > .80). Nested path analyses were conducted in Mplus Version 8.7 (Muthén & Muthén, 1998 – 2022) with models first tested including only main effects of sAA and cortisol, and then adding interaction terms. Time and location of saliva collection and gender were controlled.

Descriptive statistics and bivariate correlations are presented in Table 1. Results from path analyses are depicted in Figure 1. The main effects model provided excellent fit [χ2(10) = 6.43, p = .78; RMSEA = .00; CFI = 1.00; SRMR = .04]. sAA was significantly positively associated with physical aggression, and marginally positively associated with relational aggression. No significant effects of cortisol or associations with CU behaviors emerged. Interaction terms did not significantly improve model fit [deltaχ2(3) = 2.60, p = .46] and were nonsignificant. Findings provide additional evidence for elevated SNS activity as a risk factor for aggression in early childhood, and add to the equivocal literature on the ACM in this developmental period.

Authors

• Gretchen R. Perhamus, State University of New York at Buffalo (SUNY Buffalo)
  Presenting Author

• Jamie M. Ostrov, State University of New York at Buffalo (SUNY Buffalo)

• Dianna Murray-Close, University of Vermont