Significant Differences in Brains of Teens With Conduct Disorder

Significant Differences in Brains of Teens With Conduct Disorder
Significant Differences in Brains of Teens With Conduct Disorder

Compared with their peers, male youths with severe antisocial behavior problems appear to have significant differences in brain structure, suggesting their problem behavior stems from early life changes in brain development, according to a study by an international team published in the Journal of Child Psychology and Psychiatry.

First author Prof. Graeme Fairchild, associate professor in abnormal psychology at the University of Southampton in the United Kingdom, and colleagues used magnetic resonance imaging (MRI) to examine the brain structure of teenage and young adult men diagnosed with conduct disorder.

Conduct disorder is a cluster of persistent behavioral problems displayed in childhood and adolescence, such as aggressive and destructive behavior, stealing, and lying. In older children, it can also include staying out all night and use of weapons.

Researchers note that evidence already exists that the brains of people with serious behavior problems are different, but this tends to be simplistic and focused in limited regions, such as the amygdala - the brain’s emotion center.

However, conduct disorder is a complex behavioral disorder, and one might expect the brain differences to be more complex and affect more than one brain region, they suggest.

Therefore, in their investigation, the team looked for brain regions with similar or different thicknesses as this might indicate coordinated or non-coordinated development between regions.

For the study, researchers carried out MRI brain scans on 58 male teenagers and young adults diagnosed with conduct disorder. They also included 25 peers without such a diagnosis, as typically developing, “healthy” controls. The participants were all aged 16-21.

  Early and Late Starters

Researchers found that participants with childhood onset conduct disorder - sometimes referred to as “early starters” - had a strikingly higher number of cases where brain regions had the same thickness as controls, reported.

In contrast, the participants with adolescent-onset conduct disorder - sometimes termed “late starters” - had a lower number of cases where brain regions had the same thickness compared with controls.

Researchers confirmed the findings with a separate, independent sample of 37 participants with conduct disorder and 32 healthy controls. All participants in the second sample were male, aged 13-18.

Fairchild says the differences between the youths with both forms of conduct disorder and their healthy peers “show that most of the brain is involved, but particularly the frontal and temporal regions of the brain.”

He argues that the findings are “compelling evidence” that conduct disorder is a “real psychiatric disorder,” and not just an exaggerated form of teenage rebellion as some experts have suggested.

However, the findings do not explain how the changes come about. For example, to what extent are they influenced by people’s genes, and to what extent are they affected by the environment they are raised in?