Metacognition and diagnostic decision-making: short "blips" of knowledge and the consequences of overconfidence

When making decisions under uncertainty, we rely on the information we currently have. Presumably, the more information we have, the better our decisions turn out to be. What, though, drives our motivation to seek more information? The current research investigated people's confidence judgments in one's current information and their relationship to seeking more information when making diagnoses when presented with a sequence of medical symptoms. In Experiment 1, we explored people's confidence judgments in relation to the accumulation of information they received. In Experiment 2, we tested whether a participant's confidence levels would guide the decision to seek more information. The results showed that (1) people had the most overconfidence with a short period of exposure to medical knowledge (as opposed to a long period or none at all) and (2) that overconfidence was associated with choosing not to seek more information. In short, a "blip of knowledge" can lead to an illusion of knowing, which, in turn, could lead to a sub-optimal decision when it comes to medical diagnosing.