Summary: Research has revealed that adolescents with conduct disorder exhibit significant changes in brain structure, particularly a smaller cerebral cortex. Findings indicate reduced surface area and volume in multiple brain regions, which may affect behavior, cognition, and emotion.
The study suggests that these brain differences may help guide future diagnostic and treatment approaches. This study highlights the need for more effective interventions for conduct disorder.
Key Facts:
Brain differences: Youth with conduct disorder have reduced cortical surface area and subcortical volume. Behavioral impact: Affected areas are important for controlling problem behavior. Research implications: The findings could lead to better diagnosis and treatment of conduct disorder.
Source: NIH
Neuroimaging studies of young people who exhibit persistent patterns of disruptive, aggressive, and antisocial behavior, known as conduct disorder, have revealed significant changes in brain structure.
The most striking difference was in a smaller region of the brain’s outer layer, known as the cerebral cortex, which is important for many aspects of behavior, cognition and emotion.
The study, co-authored by researchers at the National Institutes of Health (NIH), appears in the Lancet Psychiatry journal.
“Conduct disorder represents one of the highest burdens of mental health disorders among youth. However, conduct disorder is understudied and underestimated.”
“Understanding the brain differences associated with this disorder brings us one step closer to developing more effective diagnostic and treatment approaches, ultimately aiming to improve long-term outcomes for children and their families,” said co-author Daniel Pyne, M.D., Ph.D., chief of the Division of Developmental and Affective Neuroscience at NIH’s National Institute of Mental Health.
“An important next step will be to follow the children over time to determine whether the differences in brain structure identified in this study are the cause of conduct disorder or a long-term consequence of living with the disorder.”
The researchers examined standardized MRI data from young people aged 7 to 21 years old who participated in 15 studies conducted around the world.
The analysis compared the surface area and thickness of the cerebral cortex, as well as the volume of deeper subcortical brain regions, between 1,185 youth diagnosed with conduct disorder and 1,253 youth without conduct disorder.
Additional analyses compared cortical and subcortical brain measures between boys and girls based on age of symptom onset (childhood vs. adolescence) and levels of empathy and other prosocial traits (high vs. low).
Youth with conduct disorder had lower total cortical surface area and lower surface area in 26 of 34 individual regions, and two of these regions also had significant changes in cortical thickness.
Youth with conduct disorder also had lower volumes in several subcortical brain regions, including the amygdala, hippocampus, and thalamus, which play central roles in controlling behaviors that are challenging for people with conduct disorder.
Some of these brain regions, such as the prefrontal cortex and amygdala, have been linked to conduct disorder in previous studies, but this is the first time that other regions have been implicated in conduct disorder.
Associations with brain structure did not differ between boys and girls, and were found across conduct disorder subgroups based on age at onset and levels of prosocial traits. Young people who showed signs of more severe disorders, indicated by low empathy, guilt and remorse, showed the most brain changes.
These findings, from the largest, most diverse and most thorough study of conduct disorder to date, are consistent with growing evidence that conduct disorder is linked to brain structure. The study also provides new evidence that brain changes are more widespread than previously shown, involving all four brain lobes and both cortical and subcortical regions.
These findings offer new avenues for investigating potential causal relationships between structural brain differences and symptoms of conduct disorder and for targeting brain regions as part of clinical efforts to improve diagnosis and treatment.
The study was co-led by Dr. Yidian Gao of the University of Birmingham and Dr. Marlene Staginnus of the University of Bath and conducted by the international Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) – Antisocial Behavior Working Group. The ENIGMA Consortium was funded by multiple NIH institutes through the NIH Transnational Alliance to Fund Big Data to Knowledge Centers of Excellence.
About this Behavioral Disorders and Neurodevelopment Research News
Author: Haley Kamin
Source: NIH
Contact: Hayley Kamin – NIH
Image: This image is provided by Neuroscience News
Original research: Open Access.
“Cortical structure and subcortical volumes in conduct disorder: a collaborative analysis of 15 international cohorts from the ENIGMA Antisocial Behavior Working Group,” Daniel Pyne et al., The Lancet Psychiatry
Abstract
Cortical structure and subcortical volumes in conduct disorder: A collaborative analysis of 15 international cohorts from the ENIGMA Antisocial Behavior Working Group.
background
Conduct disorder is one of the most burdensome childhood psychiatric disorders, yet its neurobiology remains unclear. Inconsistent findings limit our understanding of the role of structural brain changes in conduct disorder. This study aimed to identify the most robust and reproducible structural brain correlates of conduct disorder.
Method
The ENIGMA Antisocial Behavior Working Group conducted a collaborative analysis of structural MRI data from 15 international cohorts. Eligibility criteria were that the mean age of the sample was 18 years or younger, data on sex, age, and conduct disorder diagnosis were available, and there were at least 10 participants with conduct disorder and at least 10 typically developing participants. 3D T1-weighted MRI brain scans of all participants were preprocessed using the ENIGMA standard protocol.
General linear models were used to assess between-group differences in cortical thickness, surface area, and subcortical volumes, adjusting for age, sex, and total intracranial volume. Group-by-sex and age interactions, and comparisons of DSM subtypes (childhood onset vs adolescence onset, and low vs high levels of callous-unemotional traits) were explored. Individuals with a history of conduct disorder did not participate in the study.
Investigation result
We collected individual participant data for 1185 youth with conduct disorder (339 females (28.6%), 846 males (71.4%)) and 1253 typically developing youth (446 females (35.6%), 807 males (64.4%)). Mean age was 13.5 years (SD 3.0, range 7–21 years). No information on race and ethnicity was available.
Conduct disordered youth had smaller surface areas and total surface areas of 26 cortical regions (Cohen’s d 0.09–0.26) compared with typically developing youth. Cortical thickness differed in the caudal anterior cingulate cortex (d 0.16) and the lateral wall of the superior temporal sulcus (d –0.13). Conduct disordered youth also had smaller volumes of the amygdala (d 0.13), nucleus accumbens (d 0.11), thalamus (d 0.14), and hippocampus (d 0.12).
Most differences remained significant after adjusting for ADHD comorbidity or intelligence quotient. No group by sex or age interactions were detected. Few differences were found between DSM-defined conduct disorder subtypes. However, individuals high on callous-unemotional traits showed more extensive variance compared with controls than individuals low on callous-unemotional traits.
interpretation
“Our findings provide solid evidence of subtle but widespread brain structural changes, primarily in surface regions, in conduct disorder across subtypes and gender. These findings provide further support that brain changes may contribute to conduct disorder, warranting further consideration of this underrecognized disorder in research and clinical practice.”
Funding
Academy of Medical Sciences and Economic and Social Research Council.
