Stress-induced cortisol clouds the gut feeling in decision-making: a randomized controlled study

The notion of relying on instinctive feelings, like "following your gut," hints that bodily signals can aid in making decisions. However, stress tends to promote risk-taking, which calls into question the trustworthiness of gut feelings under stress and whether emotions consistently benefit decision-making. In a study involving 109 young adults (54 women), researchers randomly assigned half of the participants to a psychosocial stressor or a non-stressful control condition and subsequently assessed their cortisol reactivity levels.

The researchers then measured the participants' performance on the Iowa Gambling Task alongside their anticipatory skin conductance responses before each decision. The study found that stress-induced cortisol reactivity influenced the link between anticipatory skin conductance responses and risk-taking, but only in men. When men exhibited low cortisol reactivity and high anticipatory skin conductance responses, they were more likely to take risks in the gambling task.

Conversely, men with high cortisol reactivity and low anticipatory skin conductance responses also tended to engage in risk-taking. In comparison, women demonstrated no such effect and, on average, made more risky decisions than men. These findings suggest that cortisol may impair the gut feeling that typically protects against risky decisions, creating a sex-specific pathway through which stress may impact decision-making.