Children who cruelly disregard other people’s pain and psychopathic criminal offenders show dysfunction in similar brain regions— but new research finds that the changes may lead in opposite directions.
Two new studies add to conflicting literature that sometimes shows reduced activation in some nodes of a brain network involved in emotion and at other times enhanced activity. What the researchers can agree on is that the same critical circuits go awry when people who are exceptionally callous and brutal witness the pain of others.
One particularly important hub, tucked into the folds of the cortex on the border of the frontal and temporal lobes on both sides of the head, is called the insula. This region monitors the state of the mind and body: it “knows” what’s going on in the gut and the heart and how pain, need and pleasure feel, whether from heartburn, heart attack or heartache. Because the insula monitors your own emotional and physical states, it’s also important for empathizing with others.
“What does the insula really do? It helps us to feel, to be aware of our feelings,” says Jean Decety, professor of psychology and psychiatry at the University of Chicago and lead author of one of the new studies, which was published in JAMA Psychiatry.
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Decety and his colleagues studied 80 inmates, who were classified as either high, intermediate or low on scores measuring psychopathic traits. The 27 highest-scoring criminals met clinical criteria for psychopathy, which is defined by near complete lack of empathy and cold, manipulative and predatory behavior.
Participants were scanned while viewing images of people in pain or in similar situations that were not painful. For example, one image depicted someone’s hand being slammed in a car door by another person; another showed the same hand in a similar position near a car door, but not being hurt. The inmates also viewed videos of people’s faces, some expressing pain.
Unexpectedly, the researchers found significantly increased activity in the anterior insula while the psychopaths saw people in pain, compared to inmates who were not psychopathic. “I would have anticipated that it should have decreased and here we have the opposite,” says Decety. Prior research had shown that this area is the most consistently activated in research on normal people feeling empathy for pain.
“It is clearly an important study for advancing our understanding of empathy difficulties in adults with psychopathy,” says Essi Viding, professor of developmental psychopathology at University College London and lead author of the second study. He was not involved in Decety’s research.
What might explain these results? The researchers are not sure, but one potential theory involves the orbitofrontal cortex (OFC), another node in the empathy circuit, which may help people distinguish their own feelings from those related to others and determine whether behavior is socially appropriate. “The insula just tells you ‘I feel something,’ But feeling for someone, that’s the OFC and they do not activate the region,” says Decety.
Viding’s study, which was published in Current Biology, looked at the brain responses of boys with behavioral problems to images of people in pain. He compared 37 boys who engaged in behavior including stealing, fighting and bullying other kids to 18 “normal” boys of the same age. The average age of the participants was nearly 14 and they were rated on antisocial behavior by parents and teachers before being scanned. The researchers also measured “callous/unemotional traits”— a collection of cruel, uncaring and insensitive behaviors that is often seen in children who grow up to be psychopaths, although some kids do outgrow the problem.
The study found that children with conduct problems generally had reduced activity throughout the brain’s empathy network. “As a group, children with conduct problems show reduced activity in brain areas associated with empathy for pain when they view photos of others in pain,” says Viding.
“This is an invaluable study,” says Adrian Raine, professor of criminology and psychiatry at the University of Pennsylvania, who was not associated with the research. He adds, regarding the findings of reduced activation specifically associated with callousness, not just conduct problems, “The suggestion that this is an early neurobiological marker of adult psychopathy is very provocative, and potentially important.”
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Viding says that the findings could result from a reduced response to pain in general among kids who are callous and unemotional. “It may be that these children have atypical arousal response to pain,” she says, “For example, those children who are most callous may not feel pain as keenly as their peers and this may in turn mean that they find observing pain less distressing.” Similarly, prior research shows that callous children are less fearful than others— and the same is true for psychopaths. A reduction in the ability to feel both fear and pain might make such people less concerned about inducing such feelings in others.
But Viding cautions that just because these differences are seen on brain scans, it doesn’t mean that these children are genetically destined to misbehave. “Research very clearly indicates that behavioral disorders are a result of a dynamic interplay between genetic and environmental risk factors over development,” she says, “In other words, children are not born this way, nor could we use brain scans to detect whether they are or not.”
She adds, “I think it is important to be mindful of the fact that the power of neuroscience research in this area is not in trying to ‘pick out’ the next psychopath, but in developing a better understanding of how these children see the world around them. Once we understand their strengths and weaknesses better, we can also fine-tune our interventions to help these children and their families.”
Although the contradictions in the research suggest it may be a long time before the roots of psychopathy are fully understood, helping these children to better empathize could potentially prevent them from bearing poisonous fruit.