ADHD News & Research

ADHD and Conduct Disorder Cause Similar Brain Changes, New Study Says

MRI scans of adolescents with ADHD or conduct disorder traits show physical brain changes in overlapping regions, demonstrating a link between these two conditions.

September 18, 2018

Emotional dysregulation is a core, and often overlooked, symptom of attention deficit disorder (ADHD or ADD). It is commonly comorbid with mood disorders including oppositional defiant disorder, anxiety, and depression. Yet no physical link between ADHD and emotional instability disorders was documented — until last month.

A recent study1, conducted by the Swedish Karolinska Institutet and published in Molecular Psychiatry, finds biological similarities between ADHD and conduct disorder traits. The study’s researchers examined magnetic resonance imaging (MRI) scans of 1,093 adolescents. They found similar changes in the brains of youth with ADHD and those with conduct disorder traits. Both conditions manifested as reduced brain volume, and smaller surface area of the frontal lobe and nearby regions.

These findings suggest that the two conditions are related, and should be considered in tandem when diagnosing symptoms. Researchers hope their findings will lead to better understanding and treatment of patients with emotional symptoms and instability.

This study was part of the IMAGEN project, a European research mission dedicated to understanding biological, psychological, and environmental influences on adolescent brain development and mental health.


1Frida Bayard, Charlotte Nymberg Thunell, et al. “Distinct brain structure and behavior related to ADHD and conduct disorder traits.” Molecular Psychiatry, 14 August 2018. doi: 10.1038/s41380-018-0202-6