11. “Um”s and “Uh”s
LiveScience discussed a study in which researchers interviewed 52 convicted murderers in order to analyze their “linguistic tendencies.” They found that the convicts used “uh”s and “um”s more frequently than normal people. This may be because they mutter some words unconsciously, while carefully selecting which words to say. This could also be a result of psychopaths having little to no conscience, causing them to see a crime as the logical outcome of a plan.