Does perceived chronic stress really impair decision-making capacity? Evidence when deciding under varying computational demands

Chronic stress is a modern health epidemic, yet whether its impairing effects on basic cognitive capacities generalise to higher-order decision-making remains underexplored. To address this, we conducted a large (n=355), pre-registered online experiment measuring perceived chronic stress (PCS), five cognitive capacities, and decision-making capacity (via the knapsack optimisation task). This paradigm provides an objective, preference-free measure of decision-making capacity, allowing us to systematically modulate the computational demands of each decision. Surprisingly, in a broadly representative US sample, higher PCS within a `normal' range had no credible relationship with decision-making capacity or cognitive performance, even on computationally demanding decisions. However, post-hoc analyses provided a more nuanced picture, tentatively suggesting that young adults, the tertiary educated, and those with lower processing speed may be more vulnerable to chronic stress's effects. These results challenge a generalised view of stress's impact, hinting at a potential reconciliation of differential effects observed across the literature.