Researchers wanted to understand why people had this character trait and developed this lack of empathy. They went to a medium-security US prison, where 23% of the population is psychopathic. Contrary to what one might think, psychopathy is not a mental illness. Scientists define it rather as a personality disorder, a deviation from norms. Not all psychopaths are necessarily serial killers! On the other hand, they all have antisocial behavior. They never feel remorse, are incapable of normal human behavior as they fail to maintain relationships with others. In France, psychopathy would affect 2 to 3% of the population and more particularly men between 20 and 30 years old.
An analysis of the brains by MRI
The researchers chose to observe the brain activity of 212 detainees by functional MRI. The prisoners were divided into three groups according to their level of psychopathy: high, medium or low.
During this experiment, participants had to look at images representing physical pain such as a finger stuck in a door or a toe stuck under a heavy object.
The researchers then asked them to imagine that they themselves had experienced these accidents and then to think that others suffered them.
Psychopaths feel no empathy and experience pleasure.
When the psychopathic inmates imagined themselves in these painful situations, the researchers discovered on the scans a strong brain activity (even higher than normal) of the regions involved in empathy and pain. On the other hand, these regions of the brain failed to become active when the prisoners imagined that these situations were experienced by others.
Worse still, the psychopathic prisoners even showed increased activity in the region of the brain involved in pleasure.
This study was published in the magazine specializing in neuroscience: “Frontiers in Human Neuroscience”.
