Children with extreme behavioral issues have suppressed response to other's pain, states a latest study.
Researchers examined brain scans of children suffering from conduct disorders such as aggression, cruelty to others and anti-social behavior.
Some children also showed 'callous-unemotional traits,' that means a lack of guilt or compassion.
"Brain-imaging data indicate that the brain regions that seem disrupted in adults with psychopathy are also functioning in a typical fashion in children with conduct problems and callous, unemotional traits," said study researcher Essi Viding, a professor of developmental psychopathology at University College London.
The research studied 55 participant boys aged between 10 and 16. Out of these, 37 showed conduct disorder and 18 were normal. They were shown photos of hands and feet of people in painful situations and non-painful situations. At the same time they underwent functional magnetic resonance imaging (fMRI), a system to detect the measure of blood flow to various parts of the brain. The more blood flow to a part, the more active the brain region.
In the painful situation photos, hands were about to be chopped off or foot was stuck in a door and the non-painful photos showed somewhat similar images but not as raw or extreme. For instance, a hand was shown next to a knife.
Three different brain areas that play a role in empathy were focused upon. In these three areas studied, children with the disorder showed reduced brain activity after they saw the photos of painful situations.
But researchers warned that not every child with conduct disorder reacted the same way and by no means this suggests that all the children with the condition will be psychopaths once they grow into adults.
"It may be that these children have atypical arousal response to pain - 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 than their peers," Viding said. "This is just one possibility that needs to be explored further."
