Artificial intelligence technology has aided researchers in learning more about psychopaths, which has lead to two new traits found in most people with psychopathic tendencies.
The "psychopathic stare" is a big sign someone is psycho. It involves "intense eye contact and piercing eyes." Scientists found that the pupils of psychopaths don't dilate when viewing scary or graphic images. They'll also hold an intense gaze for long periods of time when lying to others or trying to persuade them.
They also found that psychopaths don't move their heads much when they're speaking to others.