Effects of acute stress on economic decision making under uncertainty

Many decisions have financial implications and economic theory provides a good framework for studying decision making processes. Economic decisions are often made in stressful situations, e.g., at the stock market, but the effects of stress on economic decision making have not been systematically investigated so far. The present study examines how acute stress influences economic decision making under risk using financially incentivized lotteries. We varied the domain of decision making (gains only, losses only, or mixed) as well as the advantageousness of the risky prospect. Importantly, no feedback was provided to isolate risk taking from learning processes. In a sample of 74 healthy young participants, 55 of whom underwent a stress induction protocol (Trier Social Stress Test for groups), we observed increased risk seeking for gains in those reacting to the stressor with a marked endocrine stress response (i.e., Cortisol respond-ers). This result shows that acute psychosocial stress affects economic decision making under risk independent of learning processes and points to the importance of Cortisol as a mediator of this effect.