The effect of acute stress on executive function in children: Moderation by parasympathetic nervous system activity.

Executive functions (EF) are crucial for children's self-regulation and academic performance. Thus, understanding factors that can undermine or promote children's EF skills, such as stress and parental social support, may inform interventions. The present experimental study tested the impact of acute stress on subsequent EF performance on four tasks assessing working memory, cognitive flexibility, and inhibitory control in 181 children ages 9 to 11 years old (M = 9.91, SD = .56). The study also examined whether parental social support prior to stress would buffer the effects of acute stress on EF, by randomly assigning children to one of three conditions: stress preceded by parent support, stress without parent support, and control (no stress task). Children in the two stress conditions experienced significantly greater physiological stress, indicated by higher cortisol and parasympathetic reactivity (p's < .001). However, the effect of condition on EF performance was not significant, F(8, 328) = 1.5, p = .16, Wilks λ = .93. Measures of physiological stress reactivity (cortisol, sympathetic and parasympathetic nervous system reactivity) were examined as moderators. Parasympathetic reactivity, as reflected by change in respiratory sinus arrythmia, was a significant moderator in the association between acute stress and inhibitory control, with children performing better under stress conditions if they had greater parasympathetic reactivity. This study suggests that children's executive function skills can be amplified or impaired in the context of mild acute stressors, and that mixed results in the literature may be due to individual differences in the activity of stress-response systems like the parasympathetic nervous system.