The Frontal Cortex

The Evolution of Psychopaths

The latest issue of Nature has a thought-provoking article on new research trying to understand the psychopathic brain. On most psychological tests, psychopaths appear perfectly normal. Their working memory isn’t impaired, they use language normally, and they don’t have reduced attention spans. In fact, several studies have found that psychopaths have slightly above average IQ’s.

So what causes the psychopath pathology? The problem seems to reside in the emotional brain: psychopaths have tremendous difficulty sympathizing with the emotions of others. When normal people are shown staged videos of strangers being subjected to pain – like a powerful electrical shock – they automatically generate a visceral emotional reaction. Their hands start to sweat and their blood pressure surges. But psychopaths feel nothing. It’s as if they were watching a blank screen. Most people react differently to emotionally charged verbs like kill or rape than to neutral words like sit or walk, but not psychopaths. The words all seem equivalent.

In the Nature article, Robert Hare, the psychologist who led the development of the PCL, or Psychopathy Checklist, speculates on why psychopaths exist:

Hare has used the PCL-SV to estimate that maybe 1 percent [of the general population] are psychopathic, even if they have never committed a crime, according to research presented recently at a meeting on psychopathy research. “Some psychopathic features are not necessarily a bad thing for society – in some professions they may even help,” says Hare. “Too much empathy, for example, on the part of a police office or a politician would interfere with the job.”

Here’s another article on the possible evolutionary origins of psychopathic violence.

Hat Tip: Mind Hacks

Comments

  1. #1 pbutler@igc.org
    December 13, 2007

    Jonah Lehrer: Their working memory isn’t impaired, they use language normally, and they don’t have reduced attention spans. In fact, several studies have found that psychopaths have slightly above average IQ’s.

    The conclusive rebuttal to anyone who says Bush is a psychopath…

  2. #2 alice
    December 13, 2007

    Very cute, pbutler.

    So what I would like to know is where did they get the psychopaths to begin with?

    We know they didn’t come from the White House, but what defines them as psychopaths? who then can be tested to find out what reactions psychopaths have?

    maybe I should read the article.

  3. #3 alice
    December 14, 2007

    yes, the information was hidden in the article…

    “Patient 13 has scored the maximum
    possible on the Psychopathy Checklist-
    Revised (PCL-R) rating scale, the ubiquitous
    tool psychiatrists use to identify the personality
    and behavioural traits that define the clinical
    syndrome ‘psychopathy’.”

  4. #4 the Big Conductor
    December 14, 2007

    Seems also to overlap with autism, which is also determined by, among a few other things, a lack of empathetic capacity.. but most autistics just tend to be very inwardly drawn, not outwardly violent.. hopefully. too many adverbs, i know ;P

  5. #5 agnostic
    December 14, 2007

    The *Human Nature* article linked to makes a small mistake: they say that there is evidence of psychopathy being a frequency-dependent strategy, but that further evidence will be needed to see if that’s true in less advanced societies.

    There’s no “but” there, even if both clauses are true. Psychopathy almost surely evolved after the transition to agriculture — too hard to get away with it in smaller H-G groups.

  6. #6 Jonathan Vos Post
    December 14, 2007

    “… in some professions they may even help…” See this fine book presenting his research to the mainstream audience:

    Snakes in Suits: When Psychopaths Go to Work by Paul Babiak & Robert D. Hare, Regan Books, 2006.

    The following reminds me uneasily about the blogosphere:

    “. . . many psychopaths come across as having excellent oral communication skills. In many cases, these skills are more apparent than real because of their readiness to jump right into a conversation without the social inhibitions that hamper most people. They make use of the fact that for most people the content of the message is less important than the way it is delivered. A confident, aggressive delivery style–often larded with jargon, cliches, and flowery phrases–makes up for the lack of substance and sincerity in their interactions with others.” (op cit, p.38).

  7. #7 Kapitano
    December 14, 2007

    A question:

    Normal people (however you define that term) can be desensitised to the suffering of others. Soldiers fighting in a war – those who don’t become shellshocked – become insensitive to killing and wounding. Indeed, people with ordinary lives sometimes have to “harden their hearts” just to do their jobs.

    So, are there observable difference in body chemistry and behavior between those who are forced to adopt a psychopathic-type personality, and those who seem to be born with it?

  8. #8 Mary
    December 14, 2007

    What I want to know is, why is it that disorders are always estimated to occur in 1 percent of the population? Schizophrenia, bipolar disorder, more obscure stuff like anosmia, and now this…. Maybe the numbers are less than 1 percent and people are just being sloppy with their rounding? Or (half-joking here) maybe there’s 1 really screwed-up percent of the population made up of schizophrenic, bipolar psychopaths who can’t smell anything?

  9. #9 Paradigm
    December 17, 2007

    From what I’ve read psychopathy consist of two components: impulsiveness and callousness. Since impulsiveness is at the core of ADHD it seems unlikely that their working memory would not be impaired or that they should have above average intelligence. In his book “Without conscience” Hare also goes on quite a bit about their odd use of language.

  10. #10 DrSteve
    December 19, 2007

    I’m pleased you used the word ‘sympathy’. It’s much more appropraite for the lack the psychopath has than ‘empathy’ – the word almost universally used. (Without empathy how could psychopaths be such great conmen?)

  11. #11 Arky
    October 8, 2010

    Psychopathic traits in police or politicians is NOT a good thing. Maybe from a personal standpoint of career advancement, but it hurts society by giving these people no qualms over corruption.

    What confuses me is the typical description of a sociopath/psychopath has them with both lots of empathy and no empathy just using those two words in different ways. They have lots of empathy in the sense that they are aware of what other people’s emotions are usually in a heightened way that allows them to effectively manipulate them, but at the same time they don’t care about those emotions.

    What if the genetic aspect is the perceptiveness rather than the lack of guilt? Maybe if someone is too emotionally perceptive they can’t handle the pain of all the negative things in the world nearly everyone is exposed to and the brain responds by shutting down the part that “cares” while still keeping up the part of empathy that “perceives”, turning what remains of their emapathy into a weapon.

    Another thing I’ve heard these people rarely care about the consequences even for themselves. Maybe this is a general deficit in “caring” rather than one specific to “caring about others”, these people don’t even really care about themselves either. The psychopath is 100% about the moment.

  12. #12 Andra Farwick
    August 8, 2011

    ur eyes r fairly

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