Add to ORKGThis paper investigates the relation between cognitive abilities and behavior in strategic-form games with the help of a novel experiment. The design allows us first to measure the cognitive abilities of sub- jects without confound and then to evaluate their impact on behavior in strategic-from games. We find that subjects with better cognitive abilities show more sophisticated behavior and make better use of information on cognitive abilities and preferences of opponents. Al- though we do not find evidence for Nash behavior, observed behavior is remarkably sophisticated, as almost 80% of subjects behave near optimal and outperform Nash behavior with respect to expected pay-offs