Abstract: Self-assessing the decisions we make through confidence judgments helps us to optimize the control of our behaviour, particularly in our relationship with the environment. Metacognitive performance, for instance overconfidence, is variable among the population and it may have some consequences in the way we treat information. We present three experimental studies that explore the relationship between metacognition and information processing. In Hainguerlot et al (2018), we study how metacognition helps us to identify sources of information. In the other two studies, we focus on how information is used. In a second study, we observed that over-confidence negatively impacts performance when subject have access to an informative cue but we also observe that this negative impacts is not due to an increased conservatism. Advice taking is studied in a third study.