Kids' brains may hold clues to future criminals

Who is going to grow up to become a criminal or psychopath?

Current research in genetics and neuroscience may point towards answers to this question, opening up a whole host of ethical questions about culpability, justice and treatment.

"Is there truly freedom of will, as the law assumes? Freedom of will may not be as free as many of us may think," said Adrian Raine of the University of Pennsylvania.

Experiments by Raine have found that by looking at the brains of 3-year-old children, scientists could already see signs of potential trouble in the future. Raine discussed this research Monday at the American Association for the Advancement of Science annual meeting in Washington.

Those who had poor amygdala function at that time were more likely to become criminal offenders later in life, in the 20-year time span during which the scientists followed them. The amygdala is an almond-shaped brain area associated with fear, and it appears that a trend among offenders is that fear conditioning is impaired. Researchers did not directly measure amygdala function in a brain scanner, but used the children's fear responses to an anticipated punishment as a proxy for that.

In fact, adult psychopaths appear to have an 18% reduction of the volume of the amygdala compared with non-psychopaths. This difference might explain why psychopaths lack remorse, fear and guilt. (Interestingly, white-collar criminals actually show enhanced brain function in decision-making and other cognitive skills, according to Raine's unpublished research).

He also noted that a brain region called the orbital frontal cortex tends to be associated with being antisocial when its volume is smaller; as a group, men have a smaller orbital frontal cortex than women, which may help explain why men as a whole tend to commit more crimes than women.

Raine is not saying that this is a perfect predictive tool; it's not going to point to which individual child is going to commit a crime. Moreover, all of the data he reports is correlational, meaning he hasn't proven that these brain abnormalities cause criminal behavior. But it doesn't seem to make as much sense to think that living a criminal lifestyle would cause impaired fear conditioning, as it would the other way around, he said.

There is also evidence that what psychologists call "callous-unemotional traits" in childhood are risk factors for becoming a psychopath. Such traits include a lack of guilt about wrongdoings, absence of feelings or emotions, unhelpfulness to someone in need and unkindness to other children.

New research in the Journal of Abnormal Psychology, also presented at the conference, looked at more than 9,500 children when they were ages 7, 9 and 12 from the United Kingdom's Twin Early Development Study. Researchers led by Natalie Fontaine at Indiana University showed that children who had hyperactivity, peer problems and emotional problems at 12 years old tended to have had increased levels of such callous-unemotional traits and conduct problems earlier in childhood.

Because participants were twins, the researchers were also able to look at genetics, and found a strong heritability for boys with high levels of persistent callous-unemotional traits. For girls with these traits that did not change much over time, environmental factors seemed to be more important.

We can look at these associations, but biology and genetics are not destiny. There will never be a perfectly accurate predictor of who will grow up to be an offender, Raine said. And 80% of delinquent adolescents do not continue to offend in adulthood, said Dustin Pardini of University of Pittsburgh Medical Center.

But by better understanding how these behaviors developed, early interventions can be adjusted to specific needs, Fontaine said.

The question from all of this becomes: If psychopaths are the way they are because of brain abnormalities or genetic influences already apparent in childhood, and should they be punished as to the same degree as other criminals?

And if they should get special treatment, "Is that not a slippery slope toward Armageddon, where none of us are responsible for our actions, because all actions and behaviors come from our brain?" Raine said.

The extent to which biological factors should play a role in the justice system is an open and highly controversial question, as is the extent to which biological interventions should be developed to reduce crime, Raine said. Preliminary research has shown that omega-3 may reduce criminal offending in prison; this is just one line of future inquiry.

What do you think: If neurological and genetic factors out of a person's control contribute to criminal offending, do we need to rethink how they are punished? If we punish people to deter others from committing crimes, does that make sense if psychopaths aren't afraid of the consequences of their actions anyway? Share your thoughts in the comments.