Chronic stress and executive functioning: A specification-curve analysis

Abstract

To investigate the association between chronic stress and executive functioning (EF), we assessed 514 young to middle-aged adults in three EF tasks (i.e., Number-Letter, 2-Back, Go/Nogo) that assessed shifting, updating, and inhibition. Chronic stress was assessed by various self-report measures and hair cortisol concentrations as indicators of subjective and objective chronic stress, respectively. In order to test the association between chronic stress and EF, we fit a structural equation model with a latent common EF factor predicted by subjective and objective chronic stress on Kaplan-Meier estimates of response times. Controlling for participants' sex, age household income and the delay between cognitive testing and hair sample collection, neither subjective nor objective chronic stress showed a meaningful association with common EF. Exploratory analyses suggested a moderation effect of income on the association between subjective chronic stress and common EF, with a smaller association for high-income participants. Additionally, we conducted a specification-curve analysis on the association between chronic stress and EF to assess the influence of different analysis choices on results in our dataset. This analysis confirmed the absence of a coherent association between chronic stress and EF by showing that the majority of analytical choices produced null effects and only a small number of analytical choices produced meaningful associations (negative or positive). Taken together, our findings suggest that common EF likely remains preserved under the influence of chronic stress. Our specification-curve analysis, however, also shows that chronic stress may also have either a positive or a negative effect on EF, depending on the choice of covariates and measures of chronic stress and EF. Consequently, more research on the role of these factors for the association between chronic stress and EF is needed to avoid the interpretation of non-replicable stress-EF associations caused by analytical choices or selection bias.

Keywords: Chronic stress; Cognitive control; Executive functioning; Hair cortisol; Specification curve.