Distinctive Brains of Psychopaths

This article was originally published in Maclean’s magazine on January 22, 1996. Partner content is not updated.

In British author Philip Kerr's futuristic novel, A Philosophical Investigation, scientists can determine whether a man is prone to violent criminal behavior by administering a brain scan to detect an abnormality.
This article was originally published in Maclean’s magazine on January 22, 1996. Partner content is not updated. In British author Philip Kerr's futuristic novel, A Philosophical Investigation, scientists can determine whether a man is prone to violent criminal behavior by administering a brain scan to detect an abnormality.

Distinctive Brains of Psychopaths

In British author Philip Kerr's futuristic novel, A Philosophical Investigation, scientists can determine whether a man is prone to violent criminal behavior by administering a brain scan to detect an abnormality. The government in the 1992 book has used the technology to construct a database of potential serious offenders. Kerr's protagonist is one of them. But when he breaks into the central computer to erase his name, he obtains the master list of other bad apples and proceeds to kill them to rid society of his "brothers." While that novelist's scenario may strike contemporary readers as farfetched, a Canadian academic is currently engaged in groundbreaking research that could ultimately produce a brain scan that would single out psychopaths. And while that is not the aim of University of British Columbia psychologist Robert Hare, his studies have shed new light on the remarkable inner workings of society's most troubled - and predatory - individuals. "We as a society are paying an enormously high cost because of this damaging disorder," says the 61-year-old Hare, a soft-spoken world authority on psychopaths. "We need to find out what makes these people tick in order to tackle the problem at its roots."

While researchers have long known what psychopaths do, they have only recently begun to learn why. In 1991, Hare and two graduate students published a landmark study suggesting that the brains of psychopaths underutilize regions that integrate emotion and memory with other information. The findings supported the long-held suspicion that the destructive behavior of psychopaths had a neurobiological basis. And while Hare is not yet prepared to draw that conclusion definitively, he and his team have made several startling discoveries about the brains of psychopaths that may eventually lead to a treatment for their now incurable disorder.

The term psychopath itself is much misunderstood and misused, especially by authors of pop fiction and Hollywood screenwriters. In the film Silence of the Lambs, the 1991 Oscar winner as best picture, a prison psychiatrist calls serial killer Hannibal "the Cannibal" Lecter a "pure psychopath." In fact, experts like Hare say that Lecter does not really qualify as a psychopath at all. "He's just insane," deadpans the professor.

In his 1993 book, Without Conscience: the Disturbing World of the Psychopaths Among Us, Hare says that confusion arises because people routinely mix up the words "psychopath" and "psycho," which is a slang expression for psychotic. The distinction is that individuals who are actively psychotic are out of touch with reality because they suffer from delusions, hallucinations or other disordered states. When they commit a violent crime, they are often found not guilty by reason of insanity and are incarcerated in a psychiatric facility rather than a jail. Psychopaths, on the other hand, are rational and quite aware of the difference between right and wrong.

Clinical psychologists have refined the definition of a psychopath over decades of research. Typically, psychopaths are charming, self-interested, glib and impulsive individuals. They often brag about grandiose life ambitions but utterly lack the skills or discipline to achieve any of their goals. Psychopaths are easily bored and crave immediate self-gratification. When caught in a lie, they quickly switch topics - or shift blame - with no apparent embarrassment. They do not form deep or meaningful attachments, and often end up hurting people who get close to them. While they are intellectually aware of society's rules, they feel no guilt when they break them.

Viewed through that prism, Hare says that Paul Bernardo, a serial rapist who graduated to serial killing, is clearly a psychopath rather than a psychotic. "Bernardo was a cold-blooded predator lacking in remorse," declares Hare. "He is a perfect example of a psychopath."

But unlike Bernardo, most psychopaths are not in jail. Hare says that the disorder does not necessarily lead to violent criminal behavior. In fact, many psychopaths find wealth and success as highly manipulative corporate careerists, as thugs on professional sports teams or as unscrupulous politicians. Experts estimate that about one per cent of the general population consists of psychopaths, while roughly one-fifth of the inmates in the country's prisons falls into the category.

But whether a criminal or a white-collar con artist, all psychopaths share a profound lack of empathy and remorse for the harm they do to others. Researchers have long suspected that the condition stems from abnormal brain function in the processing of emotion and language, rather than environmental factors such as a traumatic childhood. Hare's work is adding weight to that hypothesis. In his breakthrough 1991 study, Hare compared the brain waves of a group of normal subjects with those of psychopaths. The latter were selected from a prison population using the Psychopathy Checklist, a questionnaire Hare developed in 1980 for classifying psychopaths that has since been adopted by researchers, correctional authorities and police forces around the world.

The subjects were asked to perform a simple task: hit a button as soon as they recognized a word flashed on a computer screen. While monitoring the subjects' brain waves, the researchers alternated nonsensical strings of letters with neutral words such as "table," and emotionally evocative words like "maggot" and "cancer." What they found was that normal subjects spent more time processing emotion-laden words than the psychopaths. "When you see a word like 'cancer,' you have all sorts of associations - fear, or you think of someone who's had cancer," says Hare. "But for psychopaths, the word 'cancer' and the word 'table' had the same emotional connotations - which is to say, not very many. It's as if they're emotionally color-blind."

Even more staggering were the findings of a study conducted by New York City psychiatrist Joanne Intrator, with Hare's collaboration, at the Bronx Veterans Administration hospital in 1993. The investigators employed the same language test, this time injecting the subjects with a radioactive tracer and scanning color images of their brains. As normal subjects processed the emotion-laden words, their brains lit up with activity, particularly in the areas around the ventromedial frontal cortex and amygdala. The former plays a crucial role in controlling impulses and long-term planning, while the amygdala is often described as "the seat of emotion." But in the psychopaths, those parts of the brain appeared to remain inactive while processing the emotion-laden words. That, says Hare, helps explain why a psychopath's conscience is only half-formed. "I showed the scans to several neurologists," recalls Hare. "They said that it did not even look like a human brain. One of them asked, 'Is this person from Mars?' "

Hare's next experiment will be even more sophisticated. Slated to begin at the University of British Columbia in May, it will be run by graduate students Andra Smith and Kent Kiehl. (The latter happened to grow up three blocks from serial killer Ted Bundy's home in Tacoma, Wash., which prompted Kiehl to take up his line of study.) The researchers plan to apply the same linguistic test to 32 subjects, half of whom are psychopaths housed in a maximum-security federal prison near Vancouver. Most of those volunteers, who will be transported in shackles under armed guard, have committed violent crimes, including rapes and murders.

Hare says that the study - which was turned down for funding by the federal Medical Research Council last year, and is now privately supported by the B.C. Medical Services Foundation - will provide a better picture of what is going on inside a psychopath's brain. The reason: it will take advantage of the university's 18-month-old, state-of-the-art General Electric magnetic resonance imaging (MRI) facility - and the expertise of its scientists, radiologist Bruce Forster and physicist Alex MacKay. The unit itself, visible through a window from a control room, is a small white room equipped with a gurney that slides along a horizontal track into a short tunnel. That is where subjects lie as the machine probes their brains with magnetic torque. When Hare and his colleagues tested the procedure on a psychopathic subject last fall, the convict viewed the computer prompts through mirrors aimed at a rear-projected screen. And because the MRI is thrown off by any metal in its vicinity, the subject had to respond by pressing a touch-pad connected to a computer by fibre optics instead of a keyboard or joy stick wired with metallic cable. Capturing brain images at the rate of one every 40 milliseconds or so, the experiment effectively creates a video of the psychopath's brain as it processes emotional information.

But the researchers caution that further studies will be necessary to definitively answer the question of whether psychopaths' brains are wired differently than those of normal people. The search for a biological basis for psychopathy could lead to a treatment. If the condition arises from a breakdown in a neurotransmitter - chemicals that move signals between neurons - the behavior of psychopaths could be modified with drugs in the same way that dopamine substitutes help patients with Parkinson's disease. That day may be a long way off, but the psychopathic brain - once as perplexing as the reckless behavior it produces - is coming gradually into focus.

Maclean's January 22, 1996