Know someone who uses "uh" and "um" a lot, and cause-and-effect conjunctions like "because" and "so that"? Well, not to exaggerate, but your friend may be a psychopath. Researchers recently interviewed 52 convicted murderers in an effort to suss out the linguistic tendencies of psychopaths—and found that they see the world in mundane this-so-that terms, ignore higher-level needs, and tend to mask their madness by pausing to say "uh" and "um," LiveScience reports.
"This pattern suggested that psychopaths were more likely to view the crime as the logical outcome of a plan (something that 'had' to be done to achieve a goal)," write the authors of the study. "In lay terms, psychopaths seem to have little or no 'conscience.'" The study is driven by the idea that people choose some words—like nouns and verbs—but utter little, functional words unconsciously. The research may help police track psychopathic killers who write online, because people use some of their speech habits when writing. (Click through to see who is more cautious—psychopaths or stockbrokers.)