Neuroimaging: Kiehl & Hoffman (2011)

One particularly groundbreaking report was written by Kiehl and Hoffman in 2011. It reviewed studies that explored the neurological associations related to the behaviors behind psychopathy, specifically the areas related to moral reasoning, something that the psychopath can conceptualize and mimic rather than authentically experience. Their research also indicates a difficulty in understanding emotional context and with inhibiting their behavior.

In 2007, a neuroimaging technique called functional MRI (fMRI) that maps blood oxygenation levels in the brain was granted to a prison in New Mexico. There, researchers collected data from 1,100 inmates to capture how psychopathic and non-psychopathic individuals process emotional information. Prison, obviously enough, is the best place to study psychopathy - the unsuccessful ones, at least.

To study the neurobiology of moral reasoning, prisoners were shown a series of photo slides and asked to rate the moral context of the scenarios. Kiehl and Hoffman report that although there was no significant difference in the behavior of psychopaths and non-psychopaths recognizing the moral content of the scenarios, the psychopaths “showed decreased activation in the right posterior temporal cortex and increased activation in the amygdala,” (p. 18). The amygdala, specifically, is connected to the sensation of fear, and dysfunction in these regions may lead to a lack of understanding in how to elicit a proper response to environmental and social cues (Anderson & Kiehl, 2014).

Affective memory relates to how memories associated with emotions are stored in the brain. To study this, the test subjects were asked to recall words that included words with emotional associations as well as neutral associations. The findings showed that although psychopathic subjects remembered just as many affective (emotional) words as the non-psychopathic subjects, yet showed reduced activity in paralimbic regions of the brain and the amygdala in the psychopathic individuals. There was also increased activity in the frontal cortex, which is an area that is associated with cognitive processing. These findings suggest that psychopathic individuals rely more on intellectually knowing what an affective word means, rather than internally processing the experience of such words.

Finally, the researchers studied response inhibition. A “go-no-go” task is associated with the ability to withhold an automatic response. On a screen, test subjects were shown an “X” or a “K” in rapid succession and were asked to press a button every time the “X” appeared, but not the “K”. When they did not press the button following the “K”, it is called a response inhibition. Results showed that psychopathic individuals were much less likely to inhibit their response when the “K” stimulus appeared. 

“the regions of the brain involved in inhibition overlap the paralimbic regions, primarily the anterior and posterior cingulate….[and] may explain the psychopath’s poor behavioral controls, nomadicity, and generally impulsive lifestyle,” of both juveniles and adult psychopathic individuals (p. 19).

While Kiehl and Hoffman’s research exemplifies the psychopath’s difficulties in these faculties related to moral reasoning, they stress the fact that it does not excuse the unlawful behavior of psychopathic individuals.

Childhood Influences

If a child is born with predispositions for psychopathy, are they destined for a life of crime?

Many scholars have debated this possible connection. However, Kiehl and Hoffman (2014), who have studied psychopathy since 1999, state:

“There are studies galore that correlate the neglect and abuse of children to those children growing up with increased risks of depression, suicide, violence, drug abuse and crime. But there are currently no studies that correlate these environmental factors to psychopathy. On the contrary, a paper Hare and his colleagues presented in 1990 shows that on average there is no detectable difference in the family backgrounds of incarcerated psychopaths and nonpsychopaths. None of this means a baby born with a disposition for psychopathy is destined for it. But it does mean, as Hare has put it, “that their biological endowment—the raw materials that environmental, social, and learning experiences fashion into a unique individual—provides a poor basis for socialization and conscience formation.” (underlined for emphasis)

The ability of a child to properly socialize and form a conscious awareness of right and wrong as well as empathy and remorse can prevent some antisocial behaviors as they age, which may contribute to a decrease in deviant or unlawful behavior, interaction with law enforcement, and being labelled with childhood conduct disorder.

While scholars of psychopathy accept an idea that suggests that children who have a genetic or early developmental predisposition for psychopathy “blossom” into it as they interact with poor environments, the environment that they grow up in can also produce the type of adult psychopath who avoids crime and manages to function in society (Kiehl & Hoffman, 2014).