Psychopaths' brains wired to seek rewards, no matter the consequences

March 14, 2010, Vanderbilt University
Abnormalities in how the nucleus accumbens, highlighted here, processes dopamine have been found in individuals with psychopathic traits and may be linked to violent, criminal behavior. Credit: Gregory R.Samanez-Larkin and Joshua W. Buckholtz

The brains of psychopaths appear to be wired to keep seeking a reward at any cost, new research from Vanderbilt University finds. The research uncovers the role of the brain's reward system in psychopathy and opens a new area of study for understanding what drives these individuals.

"This study underscores the importance of neurological research as it relates to behavior," Dr. Francis S. Collins, director of the National Institutes of Health, said. "The findings may help us find new ways to intervene before a personality trait becomes ."

The results were published March 14, 2010, in .

"Psychopaths are often thought of as cold-blooded criminals who take what they want without thinking about consequences," Joshua Buckholtz, a graduate student in the Department of Psychology and lead author of the new study, said. "We found that a hyper-reactive reward system may be the foundation for some of the most problematic behaviors associated with psychopathy, such as , recidivism and substance abuse."

Previous research on psychopathy has focused on what these individuals lack—fear, empathy and interpersonal skills. The new research, however, examines what they have in abundance—impulsivity, heightened attraction to rewards and risk taking. Importantly, it is these latter traits that are most closely linked with the violent and criminal aspects of psychopathy.

"There has been a long tradition of research on psychopathy that has focused on the lack of sensitivity to punishment and a lack of fear, but those traits are not particularly good predictors of violence or ," David Zald, associate professor of psychology and of psychiatry and co-author of the study, said. "Our data is suggesting that something might be happening on the other side of things. These individuals appear to have such a strong draw to reward—to the carrot—that it overwhelms the sense of risk or concern about the stick."

To examine the relationship between dopamine and psychopathy, the researchers used positron emission tomography, or PET, imaging of the brain to measure dopamine release, in concert with a functional magnetic imaging, or fMRI, probe of the brain's .

"The really striking thing is with these two very different techniques we saw a very similar pattern—both were heightened in individuals with psychopathic traits," Zald said.

Study volunteers were given a personality test to determine their level of psychopathic traits. These traits exist on a spectrum, with violent criminals falling at the extreme end of the spectrum. However, a normally functioning person can also have the traits, which include manipulativeness, egocentricity, aggression and risk taking.

In the first portion of the experiment, the researchers gave the volunteers a dose of amphetamine, or speed, and then scanned their brains using PET to view dopamine release in response to the stimulant. Substance abuse has been shown in the past to be associated with alterations in dopamine responses. is strongly associated with substance abuse.

"Our hypothesis was that psychopathic traits are also linked to dysfunction in dopamine reward circuitry," Buckholtz said. "Consistent with what we thought, we found people with high levels of psychopathic traits had almost four times the amount of dopamine released in response to amphetamine."

In the second portion of the experiment, the research subjects were told they would receive a monetary reward for completing a simple task. Their brains were scanned with fMRI while they were performing the task. The researchers found in those individuals with elevated psychopathic traits the dopamine reward area of the brain, the nucleus accumbens, was much more active while they were anticipating the monetary reward than in the other volunteers.

"It may be that because of these exaggerated dopamine responses, once they focus on the chance to get a reward, psychopaths are unable to alter their attention until they get what they're after," Buckholtz said. Added Zald, "It's not just that they don't appreciate the potential threat, but that the anticipation or motivation for reward overwhelms those concerns."

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1.8 / 5 (8) Mar 14, 2010
The issue of nature vs. nurture..
3.8 / 5 (4) Mar 14, 2010
Is the behavior driven by the brain or is the brain modified in response to the behavior?

Brain scans are increasingly used to bolster the proposal that bad behavior is 'hardwired' into the individual, but they could more easily be used to bolster the alternate proposal that the brain is remodeled in response to behavior.

3.7 / 5 (3) Mar 14, 2010
It will be interesting to try that method to visualize the results of giving patents other drugs like antidepressants, or cognitive enhancers.
4.5 / 5 (4) Mar 14, 2010
The issue of nature vs. nurture..

Score another point for nature, damn her cruel soul.

What I don't get about these studies is that I bet you'll find similar responses amongst high achieving entrepreneurs. Maybe it's a combination of excessive reward seeking with impaired risk or social systems.
3.7 / 5 (6) Mar 14, 2010

"What I don't get about these studies is that I bet you'll find similar responses amongst high achieving entrepreneurs. Maybe it's a combination of excessive reward seeking with impaired risk or social systems"

Another item of interest is the fact that "psychopathy" appears to be functionally identical to "entrepreneurialism". These individuals are only deemed "psycho- or socio-paths" when their behavior is perceived as violent.
Ironic, when you consider the real harm -ie violence- caused by insurance cos, banking and investment, and other "captains of industry". Mere collateral damage.
3 / 5 (4) Mar 14, 2010
I would like to test these theories on a few heads of state including UN Council Members. I would also like to test it on Federal Reserve Board Members, Big Pharma Reps, FDA + CDC Doctors, some Pentagon Officials, some Military Officials, Fox News Reporters... Who else is evil?
3.7 / 5 (3) Mar 14, 2010
Who else is evil?

How could I forget? We need to test those Monsanto people for psychosis.
1 / 5 (1) Mar 14, 2010
It may be of use to replicate the experiment, only exchanging LSD-25 for methamphetamine, and introducing LSD-25 into the system before the offer of a monetary reward. Use different humans, or re-do the experiment with LSD-25 employing the same agents. I would appreciate seeing the results.
1 / 5 (1) Mar 14, 2010
It may be of use to replicate the experiment, only exchanging LSD-25 for methamphetamine, and introducing LSD-25 into the system before the offer of a monetary reward. Use different humans, or re-do the experiment with LSD-25 employing the same agents. I would appreciate seeing the results.

Oh yeah, let's get a psychopath, inject him with LSD-25, put him on a table, and feed him into clanking MRI machine. That should make him very happy. But just in case let's be sure he's strapped-down and there's a policewoman standing by named Clarice. For the reward, promise him some liver and fava beans.

Sorry, I'm not making fun of you. Your post just struck me as funny when I first read it.

Seriously, that would be an interesting experiment.
1 / 5 (2) Mar 14, 2010

Seriously, that would be an interesting experiment.

Especially when LSD's "metaprogramming" capability is considered.
Given that environmental factors have been demonstrated to have some "rewiring" effect, both separately or in conjunction with inherited traits, why not give it a try? Call it experimental therapy and see how it flies. Most people are unfamiliar with or have forgotten Dr. Leary's work, anyway.
not rated yet Mar 14, 2010
@ Caliban -- hahaha, good point. I did lose perspective, being all dorky! I haven't looked into it's research legality recently -- does anyone know if it would be possible to employ LSD-25 in such a context at this point? It seems that the compound is perfect for 'bringing to light' various facets of a developed personality, be it psychopathic, 'normalized', sociopathic, et cetera. Studying its effects through PET, fMRI, and post-interview seems tantalizing...
1 / 5 (2) Mar 14, 2010
I seem to recall some recent study(s) in the UK. But, to my knowledge, it still remains prohibited for use in studies in US- or at least in above-ground studies.
Only my opinion, of course, but it's low cost and early promise for the very purposes we are discussing are exactly why it was immediately demonized by the powers that be- natch!
not rated yet Mar 14, 2010
The clinical hold on LSD research was lifted by the FDA in 2008. Already there is research targeted to help those with schizophrenia and bi-polar depression, among other conditions.
not rated yet Mar 14, 2010
@ SJO... thanks for the lead, checking it asap!
2.3 / 5 (3) Mar 15, 2010
You forgot the head of the present US executive administration and the other psychopaths, sociopaths, and narcissists in the legislative branch.
2.6 / 5 (5) Mar 15, 2010
The comments here are pretty sad.
5 / 5 (1) Mar 15, 2010
...and so seems socially constructed reality. Not to mention the dialects of most specialized fields of inquiry. Weeping? I choose instead to lighten the
not rated yet Mar 21, 2010
ironically, if a risky drug or treatment were developed to rewire the brains of psychopaths, the psychopathic traits might make them ignore the risks of such a procedure?

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