Scans of the psychopaths’ brains looked different from both non-psychopathic criminals and non-offenders, showing noticeable abnormalities in their white and gray matter—both of which are involved with connecting brain regions. Using fMRI imaging, a team of researchers looked at the brain signaling of 50 men: 12 violent offenders—all people with antisocial personality disorder and psychopathy who had been convicted of murder, rape, attempted murder or grievous bodily harm—20 violent offenders with antisocial personality disorder but not psychopathy, and 18 non-offenders. While their brains were being scanned, the men completed an image matching test that measured their ability to change their behavior and choices based on feedback they were getting from the game. In the group of criminals who were psychopathic, the scientists observed lower volumes of gray matter in brain regions involved in empathy, moral reasoning, and the processing of social emotions such as guilt and embarrassment. The authors write that many of the characteristics of psychopathy appear very early in age, and if caught early enough, interventions could alter brain structure. “As most violent crimes are committed by men with this early-onset stable pattern of antisocial and aggressive behavior, interventions that target the specific underlying brain mechanisms and effect change in the behavior have the potential to significantly reduce the rate of violent crime,” the authors write.
– Psychopaths just don't grasp punishment the way normal people do. So say researchers who used MRI scans to analyze the brains of 12 violent psychopathic criminals, 20 violent criminals who are not psychopaths, and 18 healthy controls who are not criminals. It turns out that the psychopath cohort had a much harder time changing their behaviors and choices when playing an image matching game, as well as adapting when the rules of the game changed, reports Time. Abnormalities were seen in brain regions that process things like moral reasoning, guilt, and embarrassment. This may explain why previous research has shown that rehabilitation using negative reinforcement like punishment rarely works on psychopaths. "Psychopathic offenders are different from regular criminals in many ways," one researcher tells LiveScience. "Regular criminals are hyper-responsive to threat, quick-tempered, and aggressive, while psychopaths have a very low response to threats, are cold, and their aggressive behavior is premeditated." On the plus side, researchers hope that earlier behavioral interventions in young kids could potentially change actual brain structure and function, though not much is yet understood about how one's genes and upbringing contribute to the making of cold-blooded, psychopathic killers. (Psychopaths also seem to have a terrible sense of smell.)