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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
Anonymous
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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
Anonymous
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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."

cont...
Article Continues...

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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.

Article Continues

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#27 - 08/02/02 12:41 PM Re: Brain studies and Psychopaths
Anonymous
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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
Anonymous
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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."

Article Continues...

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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.

Article Continues...

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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.

Article Continues...

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#32 - 10/25/02 08:12 PM Re: Brain studies and Psychopaths
Anonymous
Unregistered


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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#33 - 10/27/02 02:58 PM Re: Brain studies and Psychopaths
Anonymous
Unregistered


Into the mind of a killer

Brain imaging studies are starting to venture into the legal minefield of research into criminal psychopathy. Alison Abbott reports from one of the most controversial frontiers of neuroscience.

Cesare Lombroso, the nineteenth-century 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.

Into the Mind of a Killer continues...

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#35 - 10/27/02 03:27 PM Re: Brain studies and Psychopaths
Anonymous
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Evaluation of Frontal Ventral Contribution to the Psychopathy Syndrome in a Cognitive Neuropsychological Context

Dominique Lapierre (Department of Psychology, UQAM)

Issues and Research Objectives

The purposel of this research is to establish the involvement of specific regions of the brain, the prefrontal ventral regions (orbital and median), in psychopathy.

The prefrontal regions of the brain include the frontal ventral regions and the frontal dorsolateral cortex. These two regions of the prefrontal lobe are closely linked to several other structures in the brain: they receive afferents from them and emit efferents to them. For each of the regions, the connections to other regions are different, implying specialization and different roles for each. Thus, the frontal ventral regions would then play a specific role in the processing of olfactory information. These regions would also handle integration of sensory information with that coming from the organism’s internal environment. The frontal ventral regions are also connected to the frontal dorsolateral cortex, a link that would be the basis of mediation of internal processes by external perceptions, according to the motivational significance accorded to these.

In addition to the analysis of the anatomical links between the various regions, the study of the effects of lesions also provides information on the functioning of the prefrontal regions. When lesioned, the functioning of these regions is disturbed and there appear deficits such as: lack of spontaneity, pathological inertia, impulsiveness, disinhibition and alteration of the consciousness of the self. The functions of the prefrontal regions include direction of attention, discrimination of the importance of stimuli, formation of intent, development of a plan of action, execution of the action and analysis of the results obtained. More specifically, the ventral regions are above all responsible for the social and emotional adjustment of the individual, whereas the dorsolateral regions are more centered on regulation and integration of the cognitive functions. When prefrontal lesions occur during childhood, the symptoms seem to demonstrate interference in the development of introspection, social judgment, empathy, abstract reasoning and planning.

continued...

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#36 - 09/08/04 08:44 PM Re: Brain studies and Psychopaths
Dianne E. Offline

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Registered: 11/15/02
Posts: 2788
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Source: University Of Southern California
Date: 2004-03-11

USC Study Finds Faulty Wiring In Psychopaths

Psychopaths have physical abnormalities in two key brain structures responsible for functions ranging from fear detection to information processing, a USC clinical neuroscientist has found in two studies that suggest a neuro-developmental basis to the disorder.

Adrian Raine, a professor of psychology and neuroscience in the USC College of Letters, Arts & Sciences, focused his research on two parts of the brain: the hippocampus, a portion of the temporal lobe that regulates aggression and transfers information into memory; and the corpus callosum, a bridge of nerve fibers that connects the cerebral hemispheres.

"Scientists have implicated different brain regions with respect to antisocial and aggressive behavior, and all are important and relevant," Raine said.

"But it goes beyond that to the wiring. Unless these parts of the brain are properly wired together, they'll never communicate effectively. They'll never result in appropriate behavior," he said.

Although the neurobiological roots of psychopathy are still being explored, the key behavioral features of a psychopath have been clearly defined

USC Study Finds Faulty Wiring In Psychopaths article continues...

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#37 - 06/06/05 10:22 AM Re: Brain studies and Psychopaths [Re: Dianne E.]
Dianne E. Offline

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Registered: 11/15/02
Posts: 2788
Loc: United States
Inside the psychopath
Moving ahead on diagnosis and possible treatment


Scientists may slowly be closing in on the psychopath.

New research tools, from brain scans to psychological tests, are yielding more sophisticated insights into what makes psychopaths such cold-blooded predators, raising the prospect of improved tests to identify them and possibly even treatment.

''We can treat most other emotional disorders pretty successfully, and we will be able to treat this one soon,'' said Dr. James Blair, a researcher at the National Institute of Mental Health.

Psychologists estimate that one in every 100 people is unfeeling enough to qualify as a psychopath, with an especially heavy concentration among criminals. The ranks include serial killers such as Ted Bundy, who charmed and killed dozens of young women in the 1970s, and cannibal-murderer Jeffrey Dahmer, who fatally seduced 17 men and boys before he was caught in 1991, as well as a great many other people who never commit a crime punishable by law, but go through life heartlessly using and manipulating others without remorse.

Blair is an admitted optimist, but even skeptical scientists say that the last few years have brought progress, as researchers have largely reached agreement on how to define a psychopath and have begun pinpointing what happens in their brains.

Even the last few weeks have brought intriguing new findings. Among them: A psychological test designed to detect unconscious or frowned-upon attitudes picked up a decided tendency among psychopathic murderers to have abnormally positive attitudes toward violence, British researchers reported in the May 29 edition of the journal Nature.

No one has ever pinned down that attitude among psychopaths before, said Nicola Gray, coauthor of the Nature paper, because they relied on explicit questions, and psychopaths lie a lot.

Spinal taps on more than 50 imprisoned criminals in Sweden produced new evidence that psychopaths may have an imbalance of the brain chemicals serotonin and dopamine, according to a paper in last month's Journal of Neurology, Neurosurgery and Psychiatry.

Experiments using brain scanners while psychopaths perform various tasks also have been accumulating.

They suggest that ''the psychopath finds it difficult to process, handle, or use emotional material in the same way the rest of us do,'' said Robert D. Hare, professor emeritus of psychology at the University of British Columbia and widely considered the world's foremost authority on psychopaths.

Of course, that is the obvious problem, the very definition of a psychopath: They lack normal feelings, like empathy and remorse. And researchers have known for decades that psychopaths also tend to show some unusual physical responses: They sweat less and generally exhibit less distress when exposed to frightening or threatening stimuli, for example.

But research is now focusing on the brain abnormalities in psychopaths, said Dr. Bruce Price, chief of neurology at McLean Hospital in Belmont.

And, he said, ''the seismic shift is that, up until a decade or so ago, this was the realm of psychologists and sociologists. We now are at the point where biological science can try to make sense of this.''

That point has been reached partly thanks to new tools like brain scanners, researchers say, but also partly thanks to Hare's development of a broadly accepted clinical standard for who is a psychopath, a test called the PCL-R, or psychopathy checklist-revised

Inside the Psychopath continues...

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#38 - 06/06/05 08:22 PM Re: Brain studies and Psychopaths [Re: Dianne E.]
Dianne E. Offline

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Registered: 11/15/02
Posts: 2788
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Brain potentials implicate temporal lobe abnormalities in criminal psychopaths

AbstractA prominent hypothesis of psychopathy posits it may result from abnormalities in orbital frontal cortex. However, damage to orbital frontal cortex does not lead to the full constellation of symptoms observed in psychopathy suggesting that other brain regions are implicated in the disorder. Here we report a study showing that incarcerated psychopaths’ brain potentials elicited by salient stimuli were characterized by abnormal late negativities that were more than twice the amplitude as those observed in incarcerated non psychopaths. The psychopath’s ERP abnormalities are similar to those observed in patients with temporal lobe damage. These data support the new hypothesis that psychopathy may best be conceptualized as a disorder of the paralimbic system – a system which embraces parts of the temporal lobe and frontal lobe, including orbital frontal cortex.

Psychopathy is a personality disorder defined by a cluster of interpersonal, affective and behavioral characteristics, including glibness, impulsivity, poor behavioral controls, and lack of empathy, guilt, and remorse

1,2. Psychopathic individuals are known to commit a disproportionately large amount of violent crime relative to non psychopathic individuals 3. Although there is agreement regarding the assessment and classification of psychopathy in forensic contexts, relatively little is known about the relevant brain disturbances. Historically, clinicians and researchers have made indirect inferences about the brain regions involved in psychopathy by examining changes in behavior following brain damage. For example, the case of Gage 4, which implicated the frontal lobes in psychopathic behavior 5,6. Subsequent studies of patients with frontal lobe damage suggest that orbital frontal cortex plays a pivotal role in mediating many behaviors related to psychopathy 7. Selective damage to the orbital frontal cortex leads to a condition termed ‘acquired sociopathic personality’ characterized by problems with motivation, empathy, planning and organization, impulsivity, irresponsibility, and insight. These data suggest that some aspects of psychopathy may map onto the (dys)function of orbital frontal cortex. However, the ‘acquired sociopathy’ model does not appear to fully account for the constellation of symptoms observed in psychopathy. For example, patients with orbital frontal damage rarely show instrumental or goal directed aggression – a cardinal feature of psychopathy 8. ‘Acquired sociopathic’ patients also do not exhibit the callousness commonly observed in psychopathic individuals. Similarly, patients with ‘acquired sociopathy’, unlike psychopathic individuals, are characterized by lack of insight and motivation, hoarding behavior, mood disturbances, and failure or inability to make long term plans. Psychopathic individuals, on the other hand, often enjoy making grandiose life plans – they just fail to follow through with them. Thus, while ‘acquired sociopathy’ appears to model some features of psychopathy, the two disorders differ in many respects. This raises the possibility that disturbances in brain regions other than orbital frontal cortex may contribute to psychopathy.

Studies employing event-related brain potentials (ERPs) in psychopathy have shown that during performance of a variety of cognitive and language paradigms psychopaths’ ERPs are characterized by late (500 ms post-stimulus on average) negativities 9-13. The psychopaths’ late ERP negativities are often two to three times the size as those observed in control participants. One common denominator of the studies which have observed late ERP negativities in psychopaths is that the eliciting stimuli were task relevant or salient. That is, the experimental context was manipulated in such a way as to require the participants to immediately process the stimuli. However, the interpretation that the primary processing deficit in psychopaths is related to the salience of the stimuli is hampered by the fact that the tasks shown to elicit the late ERP abnormalities in psychopaths often included relatively complex stimuli and decision making tasks. Thus, it has been difficult to isolate the neurocognitive processes underlying the late ERP negativities observed in psychopaths. Here we use an auditory ‘oddball’ task to selectively manipulate the salience of the stimuli. In oddball tasks, participants are instructed to respond (or count) low probability stimuli (i.e., salient stimuli) and to discriminate them from frequently occurring standard stimuli. The oddball task has been extensively studied and the elicited ERPs are abnormal in a variety of disorders, such as schizophrenia, depression and alcoholism. The neural systems engaged in oddball target detection are well understood and include structures in the inferior lateral frontal cortex and medial and anterior lateral temporal lobes 14-20. Our primary prediction was that during processing the salient stimuli psychopaths’ ERPs would be characterized by late ERP negativities. ERPs were recorded from 80 incarcerated participants, classified into psychopathic and nonpsychopathic groups according to scores on the Hare Psychopathy Checklist-Revised (PCL-R) 1, while they performed an auditory ‘oddball’ target detection task. Consistent with our hypothesis, analyses of the electrophysiological data revealed that psychopathic inmates, relative to demographically matched nonpsychopathic inmates, showed an aberrant large late ERP negativity during target detection (N550; see Figures 1-4). Psychopaths also had an enlarged N2b and a slightly reduced fronto-central P3 during target detection. The N550 ERP negativity was nearly twice the amplitude in psychopaths as in nonpsychopaths (see Figures 1 and 4). These data demonstrate that a simple salient stimulus discrimination between two tone types is sufficient to elicit the late ERP negativities in psychopaths. Thus, the late ERP negativities do not appear to be necessarily related to language stimuli or other complex task demands. However, the functional significance of these late ERP negativities in psychopaths still remains unclear. The auditory oddball task has been well studied in psychiatric patient populations and in patients with neurological conditions. Examination of this literature reveals that ERP studies of auditory oddball target detection in patients with selective damage to medial and anterior lateral temporal lobe indicate that abnormalities in the scalp recorded waveforms include a large early negativity (N2b), mildly reduced fronto-central positivity (P3), and an enlarged late negativity (N550) 21-23. This sequence of electrophysiological abnormalities appears to be exclusive to patients with medial and anterior lateral temporal lobe lesions or damage (see Figure 4). That is, these abnormalities have not been observed in patients with frontal lobe or parietal lobe damage during similar tasks 21,24. A comparison of the ERPs elicited by salient target stimuli for the psychopaths and the patient studies are shown in Figure 4. The similarities exist at the multiple ERP components with the enhancement of the N2b, mild reduction of the P3, and enlarged late ERP negativity. Additional support for the view that psychopathy is associated with medial and anterior lateral temporal lobe function comes from hemodynamic imaging studies of psychopathy 25-27. These studies suggest that during processing of certain types of linguistic and emotional stimuli the anterior superior temporal gyrus 25, amygdala 26,27, and hippocampus 28appear to be dysfunctional in psychopaths relative to controls. Further support for the hypothesis of abnormal medial and anterior lateral temporal lobe function in psychopathy comes from behavioral studies in patients with temporal lobe epilepsy. There is some evidence that suggests patients with temporal lobe epilepsy have a high incidence of psychopathic-like behavior 29.

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Removal of the dysfunctional anterior temporal lobe in these epilepsy patients appears to reduced hostility, increase warmth and empathy in social relationships and decrease inappropriate sexual behavior 29. Overall, these converging results are consistent with the hypothesis that medial and anterior lateral temporal lobe structures play a prominent role in psychopathy. It is relevant to note the medial and anterior lateral aspects of the temporal lobe may be conceptualized as part of the larger paralimbic system. The paralimbic system, defined by similarities in the structure of neurons and number of layers of cortex, was described by Brodmann (1909). The paralimbic system embraces classic limbic structures such as the amygdala and hippocampus and also includes anterior superior temporal gyrus, cingulate cortex and, interestingly, the orbital frontal cortex. Abnormalities in several functions of this circuitry, including error monitoring, response inhibition, and affective processing, have been observed in psychopathy. For example, regional abnormalitiesduring affective processing have recently been observed in the anterior and posterior cingulate in psychopathy 26. Additionally, brain imaging studies 30and behavioral studies of patients with brain damage to the anterior cingulate 31suggest this structure also plays a prominent role in response inhibition, a process consistently found to be dysfunctional in psychopathy 10,32. It is probable that the orbital frontal cortex plays a crucial role in the neuronal circuitry involved in psychopathy. However, dysfunction of the orbital frontal cortex does not fully account for the constellation of symptoms that comprise psychopathy. A broader view, including medial and anterior lateral temporal lobe structures and perhaps other regions of the paralimbic system, appears to account more fully for the diverse symptoms observed in psychopathy. In summary, the data from the present study suggest that psychopathy is associated with functional abnormalities in the medial and anterior lateral aspects of the temporal lobe. The medial and anterior lateral aspects of the temporal lobe are part of a larger paralimbic system which includes the anterior and posterior cingulate and orbital frontal cortex. These results, in conjunction with converging evidence from Page 7 electrophysiological and hemodynamic studies in psychopathy and with studies of lesion patients, suggest that psychopathy may best be conceptualized as a disorder of the paralimbic system rather than a disorder of a single brain region (i.e., orbital frontal cortex).

Page 8 Methods Participants. A total of 80 male inmates (ages 18-55) from a maximum-security prison near Vancouver, British Columbia volunteered for the study. Participants were free from any reported serious head injury or neurological impairment and had no DSM-IV Axis I diagnosis. IQs were normal to above normal and the mean years of formal education were greater than 10 years. The Hare Psychopathy Checklist-Revised was used to assess psychopathy 1. Inmates with a PCL-R score of 30 or above were defined as Psychopaths (n=41; mean PCL-R score 33.1 (SD 2.04)) and those with a PCL-R score below 30 were defined as Nonpsychopaths (n=39; 20.61 (SD 6.17)). Inter-rater reliability for two raters for a subset of the inmates (n=30) was .83. The mean age and years of formal education were 32.3 and 33.8, and 10.7 and 11.3 years for Psychopaths and Non Psychopaths, respectively. The National Adult Reading Test (NART) and Quick tests were used to assess IQ. NART and Quick scores for Psychopaths were 110.4 (SD 8.6) and 104.2 (SD 11.4) and for Nonpsychopaths they were 109.1 (SD 9.9) and 104.6 (SD 8.8), respectively. There were no group differences in age, years of formal education, NART or Quick scores (all Psychopath’s > .50). Each inmate was paid $5.00 for the PCL-R interview and $10.00 for the experiment. The total of $15.00 was equivalent to 2 days prison wage. The study was approved by Institutional and University ethical review boards, and participants gave written informed consent. Stimuli. The target (1500 hz tones), novel (e.g., random sounds) and standard (1000 hz tones) stimuli were presented with a probability of .10, .10 and .80, respectively (200 ms duration; 1000-1500 ms random inter-stimulus interval). Participants were instructed to respond as quickly and accurately as possible (hand counterbalanced across participants) to the target stimuli and to ignore the standard and novel stimuli.



Event-related Potential Recording. Scalp potentials were recorded from 29 electrode sites (nose reference). Electroocularogram was monitored from two electrodes located on the lateral and supra orbital ridges of the right eye. After excluding four participants for excessive artifacts (all Nonpsychopaths), there were no significant group differences in the number of trials averaged in any condition. The ERPs were digitally filtered with a zero-phase shift 30 Hz low pass filter. Three components were analyzed at midline sites by measuring the peak amplitude, relative to a 100 millisecond prestimulus baseline, in the following latency windows 175-265 ms (N2), 275-425 ms (P3), and 425-625 ms (N550). Repeated measures ANOVAs (Group: Psychopath and Nonpsychopath X Condition (Target, Novel, and Standard stimuli) x Site (Prefrontal (Fpz), Frontal (Fz), Fronto-central (Fcz), Central (Cz), Parietal (Pz) and Occipital (Oz) were performed separately for the N2, P3, and N550. ResultsBehavioral data. There were no significant group differences in the percentage of correct hits [Psychopaths 95.6 (SD 8.9); Nonpsychopaths 98.2 (SD 3.0)] reaction times [Psychopaths 424 ms (SD 79.3); Nonpsychopaths 433.6 ms (SD 74.8)] or numbers of false alarms to novel [Psychopaths 1.2 (SD 1.5); Nonpsychopaths 1.69 (SD 2.19)] or standard stimuli [Psychopaths 10.6 (SD 6.53); Nonpsychopaths 11.79 (SD 5.8]; all Psychopath’s > .15. N2 peak amplitude analyses. The N2 was larger for Psychopaths than for Nonpsychopaths (Main effect of Group: F (1, 74) = 5.17, Psychopath < .026), an effect most pronounced for target and novel stimuli [Group x Condition interaction, F (2, 148) = 3.75, Psychopath < .030** - Greenhouse-Geisser].

10P3 peak amplitude analyses. There were no significant group differences at midline sites in the amplitude of the P3 for any stimuli. However, there was a significant correlation between the amplitude of the P3 and psychopathy scores at frontal (r= -. 23, Psychopath < .05 at scalp site F8) and central sites (r= -.19, Psychopath < .05 at scalp site C4). N550 peak amplitude analyses. The N550 elicited by target stimuli was significantly larger for Psychopaths than for Nonpsychopaths at frontal and central sites (Group x Condition x Site interaction: F (10, 740) = 2.84, Psychopath < .024 – Greenhouse-Geisser).

11Figure Legends Figure 1. Grand mean ERPs (both samples) for target stimuli for psychopaths (dashed) and nonpsychopaths (solid). By convention, negative amplitude is plotted up. Tick marks are in units of 100 milliseconds. Figure 2. Grand mean ERPs (both samples) for novel stimuli for psychopaths (dashed) and nonpsychopaths (solid). By convention, negative amplitude is plotted up. Tick marks are in units of 100 milliseconds. Figure 3. Grand mean ERPs (both samples) for standard stimuli for psychopaths (dashed) and nonpsychopaths (solid). By convention, negative amplitude is plotted up. Tick marks are in units of 100 milliseconds. Figure 4. Figure Legend: Comparison of the ERP elicited by auditory oddball stimuli in criminal psychopaths (present data), patients with temporal lobe damage (Yamaguchi & Knight, 1993) and patients who had undergone anterior temporal lobectomy for the treatment of intractable epilepsy (Johnson, 1989). All three groups are typified by an enhanced N2b, diminished frontal P3, and enlarged late negativity (N550), relative to control participants. All plots are from fronto-central electrode sites and are scaled to similar amplitude and epoch.


Figure 4. Nonpsychopaths Controls Controls Psychopaths Temporal lobe damaged patients Temporal lobectomy Parietal lobe damaged patients Kiehl et al. Yamaguchi & Knight (1993) Johnson (1989)400 800ms 500 1000ms

Acknowledgements: This research was supported in part by grants from the Medical Research Council (MRC) of Canada, the British Columbia Health Services, the British Columbia Medical Services Foundation and funds from the Schizophrenia Division, Department of Psychiatry, University of British Columbia. The first author was supported by the Michael Smith Graduate Scholarship, Medical Research Council of Canada. The second author was supported by a Natural Sciences and Engineering Research Council of Canada Fellowship. These data were collected while the authors were at the University of British Columbia. We would like to thank the staff and inmates at the Regional Health Center, Abbotsford, B.C., Canada for their support and cooperation.

References1. Hare, R. D. Manual for the Hare Psychopathy Checklist-Revised (Multi-Health Systems, Toronto, 1991). 2. Hare, R. D. Without conscience: The disturbing world of the psychopaths among us (Pocket Books, New York, 1993). 3. Hemphill, J. F. (U British Columbia, Canada, 1999). 4. Harlow, J. Passage of an iron rod through the head. Boston Medical Surgical Journal 34, 389-393 (1848). 5. Damasio, H., Grabowski, T., Frank, R., Galaburda, A. M. & Damasio, A. R. The return of Phineas Gage: clues about the brain from the skull of a famous patient. Science 264, 1102-5 (1994). 6. Stuss, D. T., Gow, C. A. & Hetherington, C. R. "No longer gage": Frontal lobe dysfunction and emotional changes. Special Section: The emotional concomitants of brain damage. Journal of Consulting & Clinical Psychology 60, 349-359 (1992). 7. Damasio, A. R. Decartes' error: Error, reason, and the human brain (Grosset / Putnam, New York, 1994). 8. Anderson, S. W., Damasio, H., Tranel, D. & Damasio, A. R. Long-term sequelae of prefrontal cortex damage acquired in early childhood. Developmental Neuropsychology18, 281-296 (2001). 9. Kiehl, K. A., Hare, R. D., McDonald, J. J. & Liddle, Psychopath. F. Reduced P3 responses in criminal psychopaths during a visual oddball task. Biological Psychiatry 45, 1498-1507 (1999). 10. Kiehl, K. A., Smith, A. M., Hare, R. D. & Liddle, Psychopath. F. An event-related potential investigation of response inhibition in schizophrenia and psychopathy. Biol Psychiatry48, 210-21 (2000). 11. Kiehl, K. A., Hare, R. D., McDonald, J. J. & Brink, J. Semantic and affective processing in psychopaths: An event-related potential study. Psychophysiology 36, 765-774 (1999). 12. Williamson, S., Harpur, T. J. & Hare, R. D. Abnormal processing of affective words bypsychopaths. Psychophysiology 28, 260-273 (1991). 13. Forth, A. E. & Hare, R. D. The contingent negative variation in psychopaths. Psychophysiology 26, 676-682 (1989). 14. Halgren, E. et al. Intracerebral potentials to rare target and distractor auditory and visual stimuli. II. Medial, lateral and posterior temporal lobe. Electroencephalography and Clinical Neurophysiology 94, 229-50 (1995). 15. Halgren, E. et al. Intracerebral potentials to rare target and distractor auditory and visual stimuli. I. Superior temporal plane and parietal lobe. Electroencephalography and Clinical Neurophysiology 94, 191-220 (1995). 16. Clarke, J. M., Halgren, E. & Chauvel, Psychopath. Intracranial ERPs in humans during a lateralized visual oddball task: II. Temporal, parietal, and frontal recordings. ClinicalNeurophysiology 110, 1226-44 (1999). 17. Clarke, J. M., Halgren, E. & Chauvel, Psychopath. Intracranial ERPs in humans during a lateralized visual oddball task: I. Occipital and peri-Rolandic recordings. Clinical Neurophysiology110, 1210-25 (1999).

1818. Clark, V. Psychopath., Fannon, S., Lai, S., Benson, R. & Bauer, L. Responses to rare visual target and distractor stimuli using event-related fMRI. Journal of Neurophysiology 83, 3133-3139 (2000). 19. Kiehl, K. A., Laurens, K. R., Duty, T. L., Forster, B. B. & Liddle, Psychopath. F. Neural sources involved in auditory target detection and novelty processing: An event-related fMRI study. Psychophysiology 38, 133-142 (2001). 20. Kiehl, K. A., Laurens, K. R., Duty, T. L., Forster, B. B. & Liddle, Psychopath. F. An event-related fMRI study of visual and auditory oddball tasks. Journal of Psychophysiology 21, 221-240 (2001). 21. Yamaguchi, S. & Knight, R. T. in Slow potential changes in the brain (eds. Haschke, W., Roitbak, A. I. & Speckmann, E.-J.) 71-84 (Birkhauser, Boston, 1993). 22. Johnson, R. J. & Fedio, Psychopath. Task-related changes in P300 scalp distribution in temporal lobectomy patients. Electroencephalography and Clinical Neurophysiology. Supplement40, 699-704 (1987). 23. Johnson, R. J. Auditory and visual P300s in temporal lobectomy patients: evidence for modality-dependent generators. Psychophysiology 26, 633-50 (1989). 24. Knight, R. T., Scabini, D., Woods, D. L. & Clayworth, C. C. Contributions of temporal-parietal junction to the human auditory P3. Brain Research 502, 109-116 (1989). 25. Kiehl, K. A. et al. Temporal lobe abnormalities in semantic processing by criminal psychopaths as revealed by functional magnetic resonance imaging. Psychiatry Research: Neuroimaging (in press). 26. Kiehl, K. A. et al. Limbic abnormalities in affective processing by criminal psychopaths as revealed by functional magnetic resonance imaging. Biological Psychiatry 50, 677-684 (2001). 27. Veit, R. et al. Brain circuits involved in emotional learning in antisocial behavior and social phobia in humans. Neuroscience Letters 328, 233-6 (2002). 28. Laakso, M. Psychopath. et al. Psychopathy and the posterior hippocampus. Behavioural Brain Research 118, 187-193 (2001). 29. Hill, D., Pond, D. A., Mitchell, W. & Falconer, M. A. Personality changes followingtemporal lobectomy for epilepsy. Journal of Mental Science 103, 18-27 (1957). 30. Liddle, Psychopath. F., Kiehl, K. A. & Smith, A. M. An event-related fMRI study of response inhibition. Human Brain Mapping 12, 100-109 (2001). 31. Swick, D. & Turken, A. U. Dissociation between conflict detection and error monitoring in the human anterior cingulate cortex. Proc Natl Acad Sci U S A 99, 16354-9 (2002). 32. Lapierre, D., Braun, C. M. J. & Hodgins, S. Ventral frontal deficits in psychopathy: Neuropsychological test findings. Neuropsychologia 33, 139-151 (1995).

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#39 - 08/24/05 10:35 AM Re: Brain studies and Psychopaths [Re: Dianne E.]
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Brain Differences In Adolescents, Psychopaths, Lend To Their Impulsive, Risk-taking Behavior
Date: 2004-11-02

The next time you find yourself wondering, “Teenagers! Why do they do that?”, look to their adolescent brains. New research suggests that the risk-taking behaviors seen in adolescents may be attributed to their still developing brains. Another study explores the brain basis for the risk-taking behaviors of psychopaths.

New research—in both humans and animals—shows differences in the structure and functioning of adolescent brains compared with preadolescents or adults that correspond to such teenage behaviors as immature decision making, increased risk taking, and impulsive behaviors. As a result of this research, scientists now urge that puberty be studied as a separate stage of development—one distinctly different from the life stages of children or adults.

“Adolescents' brains seem to bias their decision-making capabilities in the direction of favoring short-term benefits, even when these benefits are weighed against potential long-term detriments,” says Jonathan Cohen, MD, PhD, of the department of psychology at Princeton University.

In one study, Gregory Berns, MD, PhD, and his colleagues at Emory University School of Medicine found that hyperactivity in the reward circuits of adolescent brains compared with adult brains may underlie adolescents' immature decision making.

Brain Differences In Adolescents, Psycho...ior...continues

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#40 - 08/24/05 11:04 AM Re: Brain studies and Psychopaths [Re: Dianne E.]
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What makes a psychopath?
By Caroline Ryan
BBC News Online health staff

Many people tell the odd white lie - taking a day off "sick" or halving the amount they spend on a shopping trip.

But most feel a little bit guilty about the deception.

Scientists have now found that twinge of conscience can be seen in increased activity in the brain.

In short, it takes more effort to lie than to tell the truth.

But people with psychopathic tendencies find lying as easy as telling the truth.

The reason is that when children develop the ability to deceive - around the age of three of four - they also develop the ability to empathise.

BBC article continues...

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#12391 - 11/30/11 09:13 PM Re: Brain studies and Psychopaths [Re: Dianne E.]
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Science News

Weaker brain links found in psychopaths
Decreased communication between emotional and executive centers may contribute

By Laura Sanders
11/30/11

Brain differences might help explain psychopaths’ cold, calculated and often antisocial behavior, and perhaps even point out better ways to treat or prevent the disorder, a study of Wisconsin prison inmates suggests.

Compared with a group of 13 non-psychopathic criminals, a group of 14 psychopaths had weaker connections between an area near the front of the brain called the ventromedial prefrontal cortex, or vmPFC, and the amygdala, a pair of almond-shaped structures deep in the brain. Earlier studies have hinted that this particular link is important for emotional regulation and aggression.

Neuroscientist Michael Koenigs of the University of Wisconsin–Madison and colleagues discovered the weaker connection by taking a mobile brain scanner to a medium-security prison. Psychopaths are overrepresented in prison populations thanks to their lack of empathy and tendency toward antisocial behavior.

After interviewing inmates and scrutinizing their disciplinary records to determine whether they were psychopaths, the scientists conducted two kinds of brain scans. The first measured the strength of brain connections called white matter tracts, which are bundles of nerves that serve as information superhighways that shuttle information between different brain regions. It was those scans that revealed the weaker link between the vmPFC and the amygdala in psychopaths, the team reports November 30 in the Journal of Neuroscience.

In the second kind of brain scan, the team assessed which brain regions were coordinating their activity while the prisoners were daydreaming. Normally, the vmPFC and right amygdala work in tandem. But in psychopaths this coordination is lower, the team found.

Finding a breakdown in vmPFC connections was particularly intriguing to Koenigs. Neurologists have long observed that after damage to this area, people can take on personality traits that are reminiscent of psychopathy, including diminished empathy and irresponsible behavior. The results offer direct evidence that the link between the vmPFC and the amygdala is compromised in psychopaths.

“This article does a marvelous job of integrating what we know about brain function,” says experimental psychologist Robert Hare of the University of British Columbia in Vancouver, who was not involved in the study. “What’s striking is that it’s confirming what clinicians have suspected and discussed and talked about. Now we’re getting down to the real nitty-gritty here.”

Hare cautions that identifying what’s different in the brains of psychopaths isn’t the same thing as figuring out the cause of psychopathy. The weakened connections seen in the Wisconsin study could be a by-product of some other environmental or genetic factor commonly found among psychopaths.

“We have a chicken and an egg, in a sense,” he says. “There’s a tendency, certainly among people in the criminal justice system, to take any of these deficits and say, ‘Wow, we have a psychopath who has all these behavioral problems, and now we have this brain anomaly or dysfunction that seems to match, therefore one caused the other.’”

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