CHICAGO — Seeing a hand slammed in a car door makes most people cringe. But others seem to lack such empathy, which might help explain why some are capable of repeatedly inflicting pain on others.
Now a study suggests that adolescents with aggressive conduct disorder — characterized by physical aggression, bullying and disregard for rules — may have robust rather than blunted reactions to others’ pain. Such adolescents may even get pleasure out of viewing other people in discomfort, Jean Decety of the University of Chicago reported February 15 at the annual meeting of the American Association for the Advancement of Science.
Using fMRI, Decety and his colleagues scanned the brains of eight adolescents with aggressive conduct disorder and eight adolescents without the disorder while showing them video clips of accidental, but painful situations.
Both groups showed activity in regions of the brain associated with pain, including the anterior cingulate cortex, insula and somatosensory cortex. But adolescents with conduct disorder showed a greater activation of these pain regions and also showed activity in the amygdala and ventral striatum, areas of the brain tied to reward responses.
“They do, so to speak, share the pain of others,” Decety said at the meeting. “But instead of finding it negative, they enjoy it.”
Those with stronger reactions in these reward areas also scored higher on standard scales for daring and sadism and reported more acts of aggression.
When viewing clips of people intentionally inflicting pain, adolescents with conduct disorder showed brain activity patterns suggesting, as expected, that they have trouble controlling their emotion, the researchers reported. Their study appears in the February issue of Biological Psychology.
Decety said the findings may have implications for intervention programs. Negative feedback, for example, may not work with adolescents who gain pleasure from such a response.
“If you enjoy it, you do it again,” Decety said.