Altered gray matter networks in the co-occurrence of autism spectrum disorder and attention deficit hyperactivity disorder.

Researchers studied brain scans from 196 people to understand how the brain differs when autism and ADHD occur together. They found that people with both conditions have unique brain network patterns that are different from having just autism or just ADHD alone. The severity of symptoms was linked to changes in a brain area called the amygdala, which is important for emotions. This research supports treating autism plus ADHD as its own condition rather than just two separate disorders.

This neuroimaging study examined brain structure differences in 196 participants across four groups: ASD with ADHD comorbidity, ASD-only, ADHD-only, and typically developing controls. Using MRI data from established databases and graph theory analysis, researchers constructed gray matter structural networks and measured topological properties. The study found both shared and unique brain network alterations across the three neurodevelopmental conditions compared to controls. Notably, in the ASD+ADHD group, symptom severity correlated with changes in amygdala connectivity patterns.

These findings provide neurobiological support for recognizing ASD+ADHD as a distinct diagnostic entity and suggest potential neural markers that could inform more targeted assessment and intervention approaches.

Results support comprehensive assessment for ASD+ADHD comorbidity and may inform development of neuroimaging biomarkers. Findings suggest need for tailored interventions addressing the unique neural profile of combined conditions rather than treating each disorder separately.

Study relies on existing database samples which may introduce selection bias. Cross-sectional design prevents establishing causal relationships. Sample characteristics and demographic details not fully specified in abstract. Replication in independent samples needed to confirm findings.

Although the comorbidity of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) (ASD+ADHD) is prevalent, the neurobiological mechanisms underlying this combined condition are not yet fully understood. Both ASD and ADHD have been associated with alterations in gray matter (GM) structural networks, suggesting that such altered GM networks may serve as potential markers for identifying this comorbid disorder. In this study, we compared the GM structural networks in ASD+ADHD, ASD without ADHD (ASD-only), ADHD without ASD (ADHD-only), and typically developing controls (TDc). Structural magnetic resonance imaging data of 41 individuals with ASD+ADHD, 53 individuals with ASD-only, 40 individuals with ADHD-only, and 62 TDc were obtained from the Autism Brain Imaging Data Exchange II and the ADHD-200 Sample databases.

Graph theory analysis was employed to construct individual GM structural networks for each participant, followed by the calculation of topological metrics based on these networks. Our analysis revealed both common and disorder-specific nodal centralities alterations across the ASD+ADHD, ASD-only, and ADHD-only groups, compared with TDc. A significant correlation was found between the severity of symptoms and altered nodal centralities in the amygdala in the ASD+ADHD group. These findings support the Diagnostic and Statistical Manual of Mental Disorders-5 diagnosis of ASD+ADHD.

Moreover, these findings provide novel neurobiological evidence for the ASD+ADHD comorbid state, which could lead to more targeted diagnostic and therapeutic approaches.