Structural (left) and functional (right) MRI scan data shows that subjects with the violence-related version of the MAO-A gene (MAOA-L) had reduced volume and activity of the anterior cingulate cortex (blue area in front part of brain at left and corresponding yellow area in at right), which is thought to be the hub of a circuit responsible for regulating impulsive aggression. The color-coded areas show where subjects with the L gene type differed from subjects with the H gene type. Source: NIMH Clinical Brain Disorders Branch

A few months ago I wrote a two-part post about how fMRI and PET scan technology were able to detect differences in the brains of psychopaths compared to non-psychopathic individuals. This area of research has identified that psychopathy has a genetic component, and has even been used in court cases to determine sentencing.

Recently, I came across a story on NPR about a neuroscientist who studies these scans, and decided to analyze his own brain scans and those of his family to determine if psychopathy was present. What he found was more than a little disturbing to him…

Researchers at MIT have recently discovered more details about the “moral center” of the brain. They’ve identified the ventromedial prefrontal cortex (VmPC)–the same part of the brain that deals with emotions–as the morality area of the brain.

Individuals who have damage to this part of their brain are more likely to have difficulty engaging in moral reasoning. So, when they are presented with imaginary situations in which one person intentionally attempts to kill another person, individuals with damage to this area of the brain do not find the attempted murderer to be at fault.

In my last post, I discussed how Dr. Kent Kiehl, a neuroscientist, is using fMRI technology to detect brain abnormalities in people with psychopathy. His participants are prison inmates who score high on the PCL-R, a psychodiagnostic measure used to assess psychopathy. Once he determines that the participant is, in fact, a psychopath based on their PCL-R score, he takes scans of their brains using an fMRI to determine if there are brain differences between psychopathic participants and normal controls. He has found defects in the paralimbic system that he believes relate to psychopathy.

Interestingly, Dr. Kiehl’s research is being used by perpetrators to avoid prison or to reduce sentencing. One such case has plagued the Chicago area for over two decades. Brian Dugan, a 52-year-old man with a 13-year crime spree, including murders, rapes, arson, and burglaries, spanning the 1970s and 80s finally went to trial for his crimes in late 2009. For those interested in death penalty laws, this case has a lot of history, and contributed to the moratorium on the death penalty in Illinois due to the wrongful conviction of three men for one of the murders (Jeanine Nicarico) that Dugan committed.

Neuroscience is a fascinating field, yet one that I often find confusing to navigate. Interestingly, there has been some research in recent years attempting to find the coordinates of psychopathy within the brain. Interviews and articles about Dr. Kent Kiehl, in which he discusses his research using fMRI technology in an attempt to target the brain region involved in psychopathy, help break down the research into more manageable terminology.

Dr. Kiehl has identified a defect in the “the paralimbic system, a network of brain regions, stretching from the orbital frontal cortex to the posterior cingulate cortex, that are involved in processing emotion, inhibition, and attentional control” as the causes for psychopathy. Psychopathy is characterized by a lack of empathy and remorse, along with severe emotional detachment.