Attention-deficit/hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder, which usually starts in childhood and often persists into adulthood. Much research has investigated whether there are structural differences between the brains of people with and without ADHD. Leading the ADHD working group of the international ENIGMA consortium, Martine Hoogman and Barbara Franke from Radboudumc earlier reported that such differences indeed existed. However, effect sizes of such findings were small on average. In the current study, Ting Li and Daan van Rooij, together with colleagues at the Human Genetics department of Radboudumc, the Donders Institute, and international ENIGMA colleagues, identified different subgroups of individuals based on brain alterations. Their findings are published in Journal of Child Psychology and Psychiatry, on March 30th 2021.
Using the large ENIGMA-ADHD cohort, consisting of 993 boys (aged 4 -14 years) and 653 adult men with and without ADHD, the researchers found that, based on subcortical profiles, boys could be stratified into four subgroups. Within each of the subgroups, the differences between those with and without ADHD were larger than in the total sample. This shows that among people with ADHD, there is considerable heterogeneity in the subcortical brain organization.
In adults, only three of these subgroups were seen in men without ADHD, while men with ADHD still showed all four subgroups. This may suggest that development of the subcortical organization of the brain occurs slightly differently in people with and without ADHD.