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.
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 A collection of nuclei found in the temporal lobe. The amygd... 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?
A 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
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
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