Study: Psychopaths Not Neurally Equipped to Have Concern for Others
First examination of neural processes related to empathy in psychopathic individuals (Apr. 24)
Prisoners who are psychopaths lack the basic neurophysiological “hardwiring” that enables them to care for others, according to a new study by neuroscientists at the University of Chicago and at the University of New Mexico.
“A marked lack of empathy is a hallmark characteristic of individuals with psychopathy,” said lead author Jean Decety, PhD.
Psychopathy affects 20% to 30% of the U.S. prison population, compared with approximately 1% of the general population. Relative to non-psychopathic criminals, psychopaths are responsible for a disproportionate amount of repetitive crime and violence in society.
“This is the first time that neural processes associated with empathic processing have been directly examined in individuals with psychopathy, especially in response to the perception of other people in pain or distress,” Decety said.
The results of the study, which could help clinical psychologists design better treatment programs for psychopaths, were published online in JAMA Psychiatry.
The researchers tested 80 male prisoners between the ages of 18 and 50 years at a correctional facility. The prisoners were assessed for levels of psychopathy using standard measures. They were then studied with functional magnetic resonance imaging (fMRI) technology to determine their responses to a series of scenarios depicting people being intentionally hurt. They were also tested on their responses to seeing short videos of facial expressions showing pain.
The participants in the high psychopathy group exhibited significantly less activation in the ventromedial prefrontal cortex, the lateral orbitofrontal cortex, the amygdala, and the periaqueductal gray parts of the brain, but more activity in the striatum and the insula, when compared with control participants, the study found.
The high response in the insula in psychopaths was an unexpected finding, as this region is critically involved in emotion and somatic resonance. Conversely, the diminished response in the ventromedial prefrontal cortex and amygdala is consistent with the affective neuroscience literature on psychopathy. This latter region is important for monitoring ongoing behavior, for estimating consequences, and for incorporating emotional learning into moral decision-making, and plays a fundamental role in empathic concern and in valuing the well-being of others.
“The neural response to distress of others, such as pain, is thought to reflect an aversive response in the observer that may act as a trigger to inhibit aggression or to prompt motivation to help,” the authors write in the paper. “Hence, examining the neural response of individuals with psychopathy as they view others being harmed or expressing pain is an effective probe into the neural processes underlying affective and empathy deficits in psychopathy.”