Raine and Yang suggest, based on research, that "antisocial groups" such as psychopaths may know what is moral, but they may lack a feeling of what is moral.
A moral "feeling," which seems to be related to the brain's prefrontal cortex and amygdala, is what takes the recognition that an act is immoral and translates that recognition into behavioral inhibition, Raine and Yang wrote. "It is this engine that functions less well in antisocial, violent and psychopathic individuals."
Jesus Pujol of the Hospital de Mar, Barcelona, Spain, and colleagues did a study published in 2012 to analyze how psychopaths' brain responses to moral dilemmas might contrast with that of non-psychopaths.
Researchers used functional magnetic resonance imaging on 22 criminal psychopathic men and 22 healthy men who were not offenders. They found that most participants gave similar responses to moral dilemmas used in the study, whether they were psychopathic or not.
But their brains told a different story: The psychopaths tended to show less activation in the medial frontal and posterior cingulate cortices in response to moral dilemmas. Researchers also found differences in the psychopaths' brains in an analysis of functional connectivity -- that is, they found impairment in the connections between some brain regions involved in morality and other areas.
Pujol's group's more recent study, published this month in the journal Biological Psychiatry, also found weakened connections in psychopaths' brains that may affect their moral reasoning. Specifically, they found that structures associated with emotion showed reduced connectivity to prefrontal areas, and enhanced connectivity in an area associated with cognition.
The results suggest that, in criminal psychopaths, the brain does not adequately use emotional information to control behavioral responses.
