Confidence ratings increase response thresholds in decision making.

Many mental processes are reactive - they are altered as a result of introspection and monitoring. It has been documented that soliciting trial-by-trial confidence ratings (CRs) reactively improves decision accuracy and lengthens response times (RTs), but the cognitive mechanisms underlying CR reactivity in decision-making remain unknown. The current study conducted two experiments and employed the drift-diffusion model (DDM) to explore why reporting confidence reactively alters the decision-making process. The results showed that CRs led to enhanced decision accuracy, longer RTs, and higher response thresholds. The findings are consistent with an increased conservatism hypothesis which asserts that soliciting CRs provokes feelings of uncertainty and makes individuals more cautious in their decision making.