Brain Imaging and Conduct Disorder: Temporal Lobe Abnormalities

Conduct disorder is a complex behavioral disorder with significant risk for later adult psychopathology.

There is increasing evidence for a biological basis for conduct disorder.

Twin studies show a significant genetic contribution to the disorder.

Brain imaging studies also point to biological factors in conduct disorder.

Gregory Wallace and colleagues recently published a structural MRI study of conduct disorder in 22 adolescents between the ages of 10 and 18. Conduct disorder subjects were compared to a group of 27 age-matched controls on imaging measures.

This study focused on measures of brain cortex thickness, brain surface area and degree of brain folding or gyrus formation.

Conduct disorder was linked to the following brain structural abnormalities:

• Reduced cortical thickness in the superior temporal lobes
• Reduced gyrus formation in the ventromedial frontal cortex
• Reduced volume of the the amygdala and striatum (putamen and pallidum) 

The research group also found a negative correlation between superior temporal lobe thickness and psychometric measures of callousness/unemotional styles.

The mechanism for the temporal lobe to be involved in the symptoms of conduct disorder is unclear. Cortical thinning in this region has been found in adults with psychopathy. 

The authors note that amygdala/temporal lobe integration is necessary for stimulus-reinforcement learning. This integration may explain some of the deficits found in the current study.

This study will be important for continuing research in the genetics and pathophysiology involved in conduct disorder. Intervention strategies will need to address potential biological deficits contributing to the behavioral and learning problems in conduct disorder.

Readers with more interest in this research can access the free full-text manuscript by clicking on the PMID link in the citation below.

Image of brain with superior temporal lobe highlighted in green is an iPad screen shot from the Brain Tutor app.

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Wallace GL, White SF, Robustelli B, Sinclair S, Hwang S, Martin A, & Blair RJ (2014). Cortical and subcortical abnormalities in youths with conduct disorder and elevated callous-unemotional traits. Journal of the American Academy of Child and Adolescent Psychiatry, 53 (4), 456-650 PMID: 24655655