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#21 - 07/18/02 10:30 PM Brain Studies and Psychopaths
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Images of violence: What use are psychopaths' brain scans?
BioMedNet
24 April 2001

High-tech scans suggest that the brains of psychopaths are not like other brains. As with DNA databanks of criminals, this information currently presents more problems than it solves.

Lawyers seeking evidence to save their clients in death penalty hearings in the United States are now focusing on brain scans, says Canadian psychologist Robert Hare, the man who developed the standard diagnostic test for determining if someone is a psychopath.

"Defense attorneys are ... beginning to look at any angle that will free their clients of culpability," Hare told BioMedNet News. "They are now looking at new developments in the neurobiology of psychopathy."

After hearing about recent research into psychopathic behavior and biology, Hare said, one lawyer told him that until now, a diagnosis of psychopathy was the kiss of death for his client in a death-penalty case. "Maybe," the lawyer said, "it will become the kiss of life."

Hare developed the diagnostic Psychopathy Checklist (PCL-R). Having studied psychopaths for more than 25 years, he estimates that they comprise 1% of the general population and 15 to 20% of the prison population.

While legal and medical experts interviewed by BioMedNet News agree that biological studies will not provide an exit pass from death row, they might someday leads to new therapies. They also might suggest ways society could protect itself from the predators who, experts agree, can feel neither empathy nor guilt.

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#22 - 07/04/02 01:46 PM Re: Brain studies and Psychopaths
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Psychobabble
The UCB
Department of Psychology Newsletter
From Nature, 410, 15 March 2001. www.nature.com

Csare Lombroso, the nineteenth-entury Italian criminologist, was the first to argue on scientific grounds that criminals are born, not made. Drawing on emerging theories of evolution and genetics, and the contemporary fad for phrenology, he concluded that those with a 'criminal mind' could be identified by deformations of their skulls. It all seemed reasonable at the time. But the facts did not fit the theory, and Lombroso's research was later discredited.

Today, many psychiatrists accept that some people who fall foul of the criminal justice system suffer from a condition--psychopathy--that is as much an illness as, for example, schizophrenia. Environmental factors may help to determine whether this 'illness' is expressed in the form of violent, criminal behaviour, but a growing number of experts argue that the underlying condition is biological. "More and more data are leading to the conclusion that psychopathy has a biological basis, and has many features of a disease," says Sabine Herpertz, a psychiatrist at the RWTH-Aachen University in Germany.

Several researchers are now using the latest brain imaging techniques in an attempt to find out what is different about the brains of psychopaths. They hope that these studies will lead to a fundamental biological understanding of psychopathy, and perhaps even to drug treatments for the condition.


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#25 - 07/05/02 02:06 PM Re: Brain studies and Psychopaths
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Scientists search for the seat of evil

USA Today
05/10/2001

At the forefront of the brain or buried near its stem is the glue of civility. It is here, science believes, that nature first raises its hand in discipline.

And it is here, it appears, that America's No. 1 villain is unable to summon the punitive pang of remorse.

When Oklahoma City bomber Timothy McVeigh meets his court-ordered demise on May 16, it is expected that he will leave the world stage in much the manner he entered it. Defiant. Unapologetic.

It's the same manner in which serial killer Ted Bundy left us in 1989 and Unabomber Ted Kaczynski remains today. The same manner in which Emile Raby confessed to a gruesome rape and attempted murder in Baton Rouge 12 years ago.

"I saw no remorse in him," recalls retired Baton Rouge police Lt. Julius O'Brien. "The ones that do it in cold blood, it doesn't take long after you interview them to see what you have. There's no feeling when they look at you and there is nothing in the eyes."

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#26 - 07/18/02 10:30 PM Re: Brain studies and Psychopaths
Anonymous
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Clues to a murderer's mind

BBC News
Psychopaths

Unlike psychotics, psychopaths appear to be sane. They can be charming and manipulative, but they are also capable of extreme acts of violence without any sense of remorse. Some 90% of serial killers are psychopathic.

Professor Robert Hare, an expert in psychopathic behaviour, measured the brainwaves of psychopaths as they were shown a series of neutral and emotional words.

He found that unlike healthy patients, the brain activity in psychopaths was no different when they were exposed to words such as "cancer" and "death".

Word deep

Professor Hare said: "Language and words for psychopaths are only word deep, there is no emotional colouring behind it.

A psychopath can use a word like 'I love you' but it means nothing more to him than if he said 'I'll have a cup of coffee'."

Professor Hare then carried out brain scans on psychopaths while they were exposed to graphic and upsetting images.

Once again, he found almost no activity in the part of the brain activated in healthy people exposed to the same images.

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#27 - 08/02/02 12:41 PM Re: Brain studies and Psychopaths
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Are psychopathic children 'blind' to fearful, sad expressions?

Crime Times
Vol. 7, No. 3, 2001 Page 3&4

Children with psychopathic tendencies have difficulty recognizing sadness and fear, according to a new British study.

D. Stevens and colleagues studied nine children who exhibited symptoms of psychopathy, and nine control children. Each child viewed sad, fearful, happy, and angry facial expressions, and listened to voices expressing these emotions. "The children with psychopathic tendencies showed selective impairments in the recognition of both sad and fearful facial expressions and sad vocal tone," the researchers say. In contrast, they did not have difficulty recognizing happy or angry expressions, or fearful, happy, and angry vocal tones.

The researchers suggest that the impairment of their psychopathic subjects may reflect early dysfunction of the amygdala, a structure located within the temporal lobes of the brain. Previous research indicates that individuals with amygdala damage due to strokes or viral infections have difficulty identifying facial expressions of fear.

The findings of Stevens et al. correlate with an earlier study by British researchers (including one member of Stevens' team). In that study last year, Derek Mitchell and James Blair showed films of people expressing different emotions to psychopathic children and adults. Both young and adult psychopaths had difficulty recognizing fearful expressions.

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#28 - 08/02/02 12:50 PM Re: Brain studies and Psychopaths
Anonymous
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PET STUDY: LOOKING INSIDE THE MINDS OF MURDERERS

What stops us from killing an irritating neighbor, a disloyal friend, or a total stranger with a pair of shoes we'd like to own? Or -- to rephrase the question -- what fails to stop some people from committing such murders?

The answer may lie, at least in part, in our frontal lobes. Much of the behavior that makes us "civilized"-self-control, maturity, judgment, tactfulness, reasoning-is regulated by this area of the brain. But new research suggests that a specific region of the frontal lobes, the prefrontal cortex, may function very differently in murderers than in the rest of us.

PET (positron emission tomography) measures the uptake of glucose, the "fuel" of the brain, by different brain areas. In a preliminary study, Adrian Raine and colleagues used PET to study differences between 22 murderers (or individuals who had unsuccessfully attempted to commit murders) and 22 carefully matched control subjects during cognitive testing.

The researchers found that the murderers had much lower levels of glucose uptake in the prefrontal cortex than controls. The differences were not related to age, gender, handedness, ethnicity, motivation, history of head injury, or presence of schizophrenia. In addition, no subjects were taking psychoactive drugs at the time of the test.

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#29 - 08/02/02 01:05 PM Re: Brain studies and Psychopaths
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PSYCHOPATHS: FINDINGS POINT TO BRAIN DIFFERENCES
Crime Times Vol. 3, No. 2, 1997 Page 4&5


Psychopaths are characterized by shallow emotions, impulsiveness, irresponsibility, egocentricity, and a lack of empathy or guilt. Robert Hare, who specializes in the study of psychopaths—who make up as much as a quarter of the prison population—characterizes them as "intraspecies predators who use charm, manipulation, intimidation, and violence to control others and to satisfy their own selfish needs." Their egocentricity, Hare says, makes psychopaths particularly dangerous; a recent FBI study, for instance, found that almost half of law enforcement officers who died in the line of duty were killed by psychopathic individuals.

"Lacking in conscience and in feelings for others," Hare says, psychopaths "cold-bloodedly take what they want and do as they please, violating social norms and expectations without the slightest sense of guilt or regret."

Traditionally, psychopathic behavior has been blamed on familial or sociological factors. Increasing evidence indicates, however, that psychopathic behavior stems not from bad parenting or a poor environment, but from fundamental differences in the psychopathic brain. Christopher Patrick et al. reported in 1995 (See related article, Crime Times, Vol. 1, No. 1/2, Page 6) that psychopaths have smaller heart rate changes and skin conductance changes in response to fear-provoking sentences than do control subjects, indicating that the processes that provoke emotions in normal subjects are defective in psychopaths. And research by Dominique LaPierre (See related article, Crime Times Vol. 1, No. 4, Page 6) suggests that the prefrontal cortex, an area of the brain involved in long-term planning and judgment, does not function normally in psychopathic subjects.

Additional studies support and extend this research, indicating that psychopaths' brains are somehow different than those of normal people. One series of studies, also by Christopher Patrick et al., compared the "startle" reaction of psychopaths and non-psychopaths.

Patrick and colleagues showed pleasant, neutral, and unpleasant slides to psychopathic prisoners. Several times during each group of slides, a loud burst of noise was delivered through subjects' headphones. Normally, the researchers note, "the protective startle reflex evoked by an abrupt, intense stimulus increases reliably during exposure to aversive or fearful stimuli, a phenomenon known as fear-potentiated startle." Thus, the startle response should be heightened when a subject views an unpleasant slide. Conversely, the reaction normally is inhibited when a pleasant slide is viewed.

In the experiments, non-psychopathic prisoners indeed reacted more strongly to the noise when they were viewing unpleasant slides, and less strongly during pleasant slides. "For psychopaths," the researchers note, "this normal pattern was not obtained. Instead of showing heightened startle reactions during exposure to aversive slides, the reactions of psychopaths were actually inhibited, relative to neutral slides."

Other studies by Patrick et al. have produced similar results. The researchers conclude that "the absence of normal startle potentiation in psychopaths during exposure to aversive pictures or warning cues signifies a deficit in the capacity for defensive response mobilization, which is the essence of fear."

The two hallmarks of psychopathy are emotional detachment and antisoical behavior, but Patrick et al. have found that only emotional detachment is linked to abnormal responses to unpleasant slides. This indicates, they say, that the "fear deficit" of psychopaths "is tied specifically to the affective/interpersonal component of psychopathy."

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#30 - 08/02/02 01:09 PM Re: Brain studies and Psychopaths
Anonymous
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Brainwave tests reveal abnormalities in psychopathy, conduct disorder

Crime TImes
Vol. 5, No. 4, 1999 Page 3

Two new studies, both using event-related potentials (ERPs), report that criminal psychopaths and teenagers with conduct disorder have abnormal responses to stimuli.


Kent Kiehl and colleagues studied a particular brainwave response, known as the P300, in 11 psychopathic and 10 non-psychopathic prison inmates. (Psychopaths, who are characterized by egocentricity, shallowness, manipulativeness, deceitfulness, selfishne ess, and lack of empathy, remorse, or guilt, are generally more dangerous and far less responsive to rehabilitation efforts than other prisoners.)

The researchers measured subjects’ response to a visual “oddball” task, in which the participants responded to a low-probability visual stimulus. The P300 response to an “oddball” task, Kiehl et al. say, “is thought to be sensitive to changes in the alloc cation of attentional resources and processes involved in contextual updating and decision making.”

The researchers report that among non-psychopathic subjects, the amplitude of the P300 was larger when target stimuli appeared than when other stimuli appeared. “In contrast,” they say, “psychopaths failed to show reliable P300 amplitude differences betwe een the target and non-target conditions,” and exhibited a smaller amplitude P300 in response to target stimuli than did other subjects. In addition, the psychopaths’ P300 response was less lateralized, which the researchers say is interesting in light of f f evidence indicating that psychopathy is associated with weak or abnormal lateralization of the cerebral hemispheres.

The researchers also found that the psychopaths exhibited an abnormal late centro-frontal negative wave (N550) when target stimuli were presented. This is the first study to identify this abnormality among psychopaths doing a task that did not require lin nguistic processing.

Overall, the researchers say, their findings suggest that “psychopaths are abnormal in their ability to mobilize and rapidly focus attention to stimuli to which they are required to respond. Once focused, it may be extremely difficult for them to remobilize and switch attentional resources.”

Conduct disorder: similar findings
Lance Bauer and Victor Hessel-brock used a similar visual oddball task to measure the P300 responses of 257 subjects between the ages of 15 and 20, and found that “P300 amplitude was smaller among subjects reporting a greater number of conduct problems prior to age 15 vs. those reporting fewer problems of this type.” This finding, they say, adds to evidence indicating that conduct problems are associated with subtle brain dysfunction. One interesting finding, they add, was that P300 amplitude reductions were noted only in the posterior region in conduct-disordered teens younger than 16, while reductions were seen only over the frontal region in older conduct-disordered teens.

Noting that a family history of alcohol or drug dependency did not have a significant effect on P300 amplitude, the researchers suggest that P300 decrements associated with substance abuse by other studies may in fact be related to undiagnosed conduct disorder.

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#31 - 08/02/02 01:22 PM Re: Brain studies and Psychopaths
Anonymous
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THE PSYCHOPATHIC BRAIN: NEW FINDINGS

Crime Times
Vol. 1, No. 4 , 1995, Page 6

Crime Times recently reported evidence, from a study by Adrian Raine, that abnormalities in the prefrontal cortex of the brain may be linked to violent crime (See Crime Times, Vol. 1, No. 1/2, Page 1). Now a Canadian study suggests that psychopathic behavior also may be linked to deficits in this region of the brain.

Dominique LaPierre et al. compared 30 psychopaths to 30 non-psychopathic criminals, using tests that measure the functioning of two different areas of the prefrontal cortex (the orbitofrontal and frontal ventromedial areas). Their data, the researchers say, revealed that "the psychopaths were significantly impaired on all the orbitofrontal- ventromedial tasks" in comparison to the non-psychopathic criminal controls. No differences were seen when tests measured the function of other areas of the frontal cortex.

One particularly interesting discovery was that psychopathic subjects were quite impaired on a test requiring them to select the verbal label for an odor. (The test was selected because patients known to have orbitofrontal damage do poorly at this task.) "This... finding is particularly important," the researchers say, "in the sense that it cannot readily be explained socioculturally, thus presenting a new and convincing argument for brain-based etiology of this disorder."

LaPierre and colleagues note that their findings are not surprising in light of the striking similarities between psychopaths and patients with prefrontal cortex damage. "Both the psychopath and the orbitofrontal or ventromedial frontal patient show an exaggerated preoccupation with sexual matters, acting in a promiscuous and impersonal maladaptive way," they say. "Both are remarkable for their lack of social and ethical judgment. Both neglect long-term consequences of their actions, choosing immediate gratification over careful planning."

The researchers caution, however, that the deficits they discovered may not, in and of themselves, explain psychopathic behavior. They note that a number of brain regions are involved in inhibiting inappropriate behavior, and that a disruption in any part of this "behavior inhibition circuit" could cause the disinhibition, distractibility, and sensation-seeking behaviors characteristic of psychopaths.

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#32 - 10/25/02 08:12 PM Re: Brain studies and Psychopaths
Anonymous
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Notes on the video "The Mind of the Psychopath"

DESCRIPTION

This program opens in the middle of an interview with Patrick Frisell, serving time for manslaughter in a Canadian prison describing his chances for parole. The narrator describes Frisell's participation in a study of psychopathy conducted by Dr. Robert Hare of the University of British Columbia. Hare defines psychopathy as a clinical construct characterized by a cluster of behaviors. The cluster includes interpersonal, affective, and socially deviant behaviors.

The narrator describes specific behaviors related to psychopathy as: callous, impulsive, manipulative, glib, egocentric, predatory, grandiose, with a lack of empathy and emotional affect. Hare reviews his twenty-five year history studying the psychopathic personality and the development a various measuring tools. The narrator describes the Hare Psychopathy Check List-Revised (PCL-R). The assessment procedure involves the integration of file information and collateral data gather by a trained clinician shown interviewing a client.

Frisell is seen walking to Hare's laboratory where he will participate in a lexical decision task requiring him to press a key in response to neutral words, non-words, and emotional words. His brain is monitored by means of EEG during the task. Hare discusses the results with Frisell. The narrator describes yet another brain measuring technique involving magnetic resonance imagining. A rotating computerized image of Frisell's brain reveals no structural anomalies.

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