17 October 2011
Software identifies psychopaths
by Kate Melville
Using computer software to analyze the speech patterns of psychopathic killers shows they make readily identifiable subconscious word choices when talking, a finding with intriguing implications for law enforcement and social media networks. Details of the research appear in the journal Legal and Criminological Psychology.
"The words of psychopathic murderers match their personalities, which reflect selfishness, detachment from their crimes and emotional flatness," explained one of the study's authors, Jeff Hancock, a Cornell professor of computing. Hancock undertook the study with colleagues at the University of British Columbia.
For the study, the researchers analyzed stories told by Canadian psychopathic male murderers and compared them with convicted murderers who were not diagnosed as psychopathic. Each subject was asked to describe his crime in detail. Their stories were taped, transcribed and then subjected to computer analysis.
The findings showed that psychopaths used more conjunctions like "because," "since" or "so that," implying that the crime "had to be done" to obtain a particular goal. They also used twice as many words relating to physical needs - such as food, sex or money.
Non-psychopaths used more words about social needs; including family, religion and spirituality. Intriguingly, the psychopaths often included details of what they had to eat on the day of their crime.
Psychopaths were more likely to use the past tense, suggesting a detachment from their crimes, the study notes. They also tended to be less fluent in their speech, using more "ums" and "uhs." Hancock isn't sure why this is so, but speculates that the psychopath is trying harder to make a positive impression, needing to use more mental effort to frame the story.
"Previous work has looked at how psychopaths use language," Hancock concluded. "Our paper is the first to show that you can use automated tools to detect the distinct speech patterns of psychopaths."
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Source: Cornell University