Knowing Neurons
Did You Know?Neurological and Psychiatric Disorders

The Psychopathic Brain: Broken and Free of Blame

What is it about a cold-hearted psychopath that intrigues us so?

People who are known psychopathic serial killers like Ted Bundy and John Wayne Gacy instill fear in us, but they also bring us some curiosity.  Perhaps the fear stems from our inability to comprehend and identify with their actions and the motives that drive them.  This is probably a good thing because it’s an indicator that we are not on the same playing field.

It has been suggested that, unlike the general population, psychopaths are incapable of experiencing the full range of human emotions.  However, they are experts at masking this inability and feigning them (Cleckley, 1941), making them potentially dangerous as members of a society.

Psychopathy is a personality disorder.  A stereotypical psychopath would be extremely egocentric and able to callously manipulate and deceive the people around him (or her) to help accomplish his personal goals.  If the people he manipulated got hurt in the process, he would not be able to feel empathy or remorse.

Why are these people like this?  Perhaps biology can shed some light on it.  Researchers have observed that criminal psychopaths differ in their physiology.  They don’t sweat or blink when they’re startled in the way most people do (Hare, 1971; Patrick, 1994).  Additionally, psychopaths process and respond to emotional images and language differently from other people (Hare et al., 1988; Patrick, 1994).  They also make abnormal moral judgments, such as endorsing harm to a person when the decision is personally profitable or beneficial enough (Koenigs et al., 2012).  All of this has led researchers to believe that psychopaths’ brains are not processing emotions normally.

Amygdala and ventromedial prefrontal cortex via Knowing Neurons
The ventromedial prefrontal cortex and amygdala work together to process and regulation emotion.  In psychopaths, the circuit between these two brain regions function abnormally. (Image via)

New brain imaging of psychopaths shows evidence that suggests functional differences in certain brain regions involved in emotion regulation and behavioral control.  Parts of the brain called the ventromedial prefrontal cortex and amygdala are two neural regions that are densely interconnected and work together to process and regulate emotion (Davidson, 2002; Kalin et al., 2004).  In psychopaths, the circuit between these two parts of the brain functions abnormally.  In tests, psychopaths were shown to process differently stimuli for fear conditioning, processing emotions, and moral decision-making (Birbaumer et al., 2005; Kiehl et al., 2001; Glenn et al., 2009).  But the story is more complicated than a neural circuit that simply does not activate when it should.  The brain is a series of interconnected networks, and it is likely that many other regions are involved in the disorder.

So, is it biology or environment?  It appears to be both.  Certain psychopathic traits are passed on genetically, and it has been suggested that genetic vulnerabilities may be worsened by environmental factors, like parenting style (Larsson, Viding, and Plomin, 2008).

Psychopaths have been shuffled between mental institutions, prisons, and society for hundreds of years.  We are a ways off from pinpointing the exact etiological and neurobiological underpinnings of the disorder, and as scientists try, the question of what the legal implications would be for people diagnosed as psychopaths is raised.  What if there was one spot in the brain that we could point to that would explain why psychopaths do not process, express, or use emotions like others?  Would this biological explanation reduce blame in the courtroom?  Is this person guilty or not guilty for crimes like murder?  Would such explanations lead to more or less punishment for these individuals?

Neurolaw via Knowing NeuronsA recent study found that U.S. state trial judges deliberating over hypothetical case descriptions delivered significantly shorter prison sentences to convicts diagnosed with psychopathy, but only when a “biomechanical” cause was listed for the disorder (Aspinwall et al., 2012).  This might lead us to believe that any personality trait or behavior that could be explained biologically could be used as an excuse for reduced sentences or fewer prosecutions.  But should that be the case?  Ultimately, the case could be made that biology can explain every behavior and personality trait.  Psychopathic inmates are the most dangerous criminals and the most likely to recommit crimes upon being released from prison (Hare, 2011).  We might want to regard leniency in the courtroom toward biological explanations of crimes with caution.

Psychopaths are a good example of what happens when emotional processing in the brain goes awry.  Although further research is needed to uncover the causes of psychopathy, the ultimate goal will be to develop potential treatments for the disorder, with the hopes of lessening the burden of this population on society.


Written by Mona Sobhani


The Psychopathic Brain: Broken and Free of Blame via Knowing Neurons


Aspinwall L.G., Brown T.R. & Tabery J. (2012). The Double-Edged Sword: Does Biomechanism Increase or Decrease Judges’ Sentencing of Psychopaths?, Science, 337 (6096) 846-849. DOI:10.1126/science.1219569

Birbaumer, N., Veit, R., Lotze, M., Erb, M., Hermann, C., Grodd, W., & Flor, H. (2005). Deficient fear conditioning in psychopathy: a functional magnetic resonance imaging study. Archives of general psychiatry, 62(7), 799. DOI:10.1001/archpsyc.62.7.799

Cleckley, H. (1941). The Mask of Sanity: An Attempt to Reinterpret the So-Called Psychopathic Personality, JAMA: The Journal of the American Medical Association, 117 (6) 493. DOI:10.1001/jama.1941.02820320085028

Davidson R.J. (2002). Anxiety and affective style: role of prefrontal cortex and amygdala, Biological Psychiatry, 51 (1) 68-80. DOI: 10.1016/S0006-3223(01)01328-2

Glenn, A. L., Raine, A., & Schug, R. A. (2009). The neural correlates of moral decision-making in psychopathy. DOI: 10.1038/mp.2008.104

Hare, R. D. (2011). Without conscience: The disturbing world of the psychopaths among us. Guilford Press.

Hare, R. D., Williamson, S. E., & Harpur, T. J. (1988). Psychopathy and language. In Biological contributions to crime causation (pp. 68-92). Springer Netherlands.

Hare R.D. & Quinn M.J. (1971). Psychopathy and autonomic conditioning., Journal of Abnormal Psychology, 77 (3) 223-235. DOI: 10.1037/h0031012

Kalin, N. H., Shelton, S. E., & Davidson, R. J. (2004). The Role of the Central Nucleus of the Amygdala in Mediating Fear and Anxiety in the Primate, Journal of Neuroscience, 24 (24) 5506-5515. DOI: 10.1523/JNEUROSCI.0292-04.2004

Kiehl, K. A., Smith, A. M., Hare, R. D., Mendrek, A., Forster, B. B., Brink, J., & Liddle, P. F. (2001). Limbic abnormalities in affective processing by criminal psychopaths as revealed by functional magnetic resonance imaging. Biological psychiatry, 50(9), 677-684. DOI: 10.1016/S0006-3223(01)01222-7

Koenigs M., Kruepke M., Zeier J. & Newman J.P. (2012). Utilitarian moral judgment in psychopathy,Social Cognitive and Affective Neuroscience, 7 (6) 708-714. DOI: 10.1093/scan/nsr048

Larsson H., Viding E. & Plomin R. (2008). Callous Unemotional Traits and Antisocial Behavior: Genetic, Environmental, and Early Parenting Characteristics, Criminal Justice and Behavior, 35 (2) 197-211. DOI: 10.1177/0093854807310225

Patrick C.J., Cuthbert B.N. & Lang P.J. (1994). Emotion in the criminal psychopath: Fear image processing., Journal of Abnormal Psychology, 103 (3) 523-534. DOI: 10.1037//0021-843X.103.3.523

Images adapted from Rutgers, Ocean/Corbis, and Oliver Sved/Shutterstock, and made by Jooyeun Lee and Kate Jones.  


  • knowingneurons

    Knowing Neurons is an award-winning neuroscience education and outreach website that was created by young neuroscientists. The global team members at Knowing Neurons explain complicated ideas about the brain and mind clearly and accurately using powerful images, infographics, and animations to enhance written content. With an extensive social media presence, Knowing Neurons has become an important science communication outlet and resource for both students and teachers.


Knowing Neurons is an award-winning neuroscience education and outreach website that was created by young neuroscientists. The global team members at Knowing Neurons explain complicated ideas about the brain and mind clearly and accurately using powerful images, infographics, and animations to enhance written content. With an extensive social media presence, Knowing Neurons has become an important science communication outlet and resource for both students and teachers.

8 thoughts on “The Psychopathic Brain: Broken and Free of Blame

  • Psychopaths are free of blame. I have had a two year ‘relationship’ with one which was quite impossible because their brains don’t grasp the concept of relationship. They are so egocentric by biology that there is nothing outside of themselves. It is difficult for the non-psychopath to comprehend but the longer they are with them the more disoriented and confused the person becomes. The psychopathic mind can do nothing but abuse and that is a fact and this will not change. I believe there should be a public awareness campaign to educate against the dangers of coming in to contact with a psychopath. It is estimated that 1 in 100 men (and less women) have the neurological make up a psychopath. Environment is a key factor in how much damage a psychopath is likely to do. The psychopathic traits are exaggerated when there has been a history of childhood abuse. Considering the high rate of domestic abuse, marriage break ups and violence normalized in the media, I think we can count on a future dominated by psychopathy. Or maybe the present is already dominated by it. We now have the knowledge through neuroscience of a problem that has plagued humanity in the psychopath. And it is in our humanity that we should solve this problem . If there was mandatory testing on the brains of the people who govern us, including corporate chiefs the public would be shocked. These tests would not eventuate for that very reason. In the U.S there is a combined degree in Law and Neuroscience (in Boston I think). This could be the starting point of how psychopathy can be evaluated in the legal domain but not necessarily bring justice. Public protection always seems to come ipso facto. I think it is now time for Neuroscience to leave the lab and go beyond te objectivism of science and partake in a public education on the inherent dangers of the psychopaths amongst us. I don’t seek to exact revenge upon them, they truly can’t help their behavior. Nor do I want society to remain vulnerable and ignorant or even paranoid of psychopathy. Science has never been neutral it is how the science has been applied which shapes the outcomes. A public education does not need to target individual psychopaths but it needs to educate on the general behaviors the psychopath employs. More importantly I think a general neuroscience course should be started in primary school. We should get to know and appreciate our own brains and then we would value them, and ourselves more. We should be facilitated in the awe of that which is between our ears! When we get to know our own body and being we are in a better place and less likely to be victims of psychopaths.

  • Great article! Until the lawyers and judges acknowledge the problems psychopathy creates, nothing will be done.

    I started my blog. for exactly this reason. My ex wife lied and fooled the court over and over. When I brought up her high conflict behavior and linked it to psychopathy, they turned a blind eye. No discussion or debate. The judges have flat out refused to address parental alienation because they recognize the origins are psychological and don’t wish to address psychopathy.

    • Kaaren

      To Goodmendidnothing. Psychopaths gravitate to positions of power and what better positions are there than Judges and lawyers?

      • Karen,

        You are absolutely correct. Lawyers and Judges. It does not matter what you think. Only what they think is important. You must be punished if you disagree.

        Look at my case and you can see how the judge put himself ahead of the best interest of children. Protecting children will admit a problem that existed long before and they chose not to see it.

        If they did what they were supposed to do they would have clean hands. Now they are covering up for their failure to adequately protect children from a foreseeable harm.

        They are all in denial over the damage they create.

  • Jennifer Smith, True Love Scam Recovery

    Thank you so much for this well researched, accurate, article. Until the courts, police, therapists and the like catch up to the reality that these people are what is behind many a “bad-boy”, abusive man, gold-digger female, mean politicians, endless corporate greed mongers and downright criminals – we as the victims of some of these monsters are waving the flag high declaring “relationships” with these freaks-of-nature are not relationships but impersonal crimes. Sociopaths go after the best of the best seeking trusting, loyal, good-hearted giving people with skills, persistence, money (any amount will do) or a specific citizenship to steal from, get a couch to sleep on, a place to shower, a facade to sit behind or a country to enter for their personal gain. The fallout of their twisted “normal” is many, many peoples’ harm, trauma, loss, devastation and unlimited danger – it must be reframed by each target or prey from the point of view of what these “people” truly are in order to recover and heal. – Keep on getting the word out.

Comments are closed.