Attention-Deficit/Hyperactivity Disorder ADHD involves robust alterations in the cortical cerebral mantle, as shown in a recent article by Òscar Vilarroya and colleagues from the Neuroimaging Research Group at the IMIM-Hospital del Mar. These alterations are most prominent in brain regions involved in attention processing, and are more common in the childhood form of the disorder than in the adult one.
ADHD is a psychiatric and neurobehavioral disorder characterized by either significant difficulties of inattention or hyperactivity and impulsiveness or a combination of the two. Although it was initially regarded as a disorder exclusive to childhood – affecting about 3 to 5 percent of children globally -, nowadays its prevalence in adulthood is well established.
Previous research on children with ADHD has shown a general reduction of brain volume, but with a proportionally greater reduction in the volume of the left-sided prefrontal cortex. The researchers at the IMIM have now used anatomical brain MRI scans to analyse cortical thickness in 41 normal children and 43 children with ADHD, as well as three groups of adult individuals: 31 normal, 31 ADHD patients treated with stimulants and 24 medication-naïve ADHD patients.
The results, published in PLoS One, show several clusters of reduced laminar cortical thickness in ADHD patients in comparison to neurotypical individuals. These differences were primarily located in the dorsal attention network.
Hoekzema E, Carmona S, Ramos-Quiroga JA, Fernández VR, Picado M, Bosch R, Soliva JC, Rovira M, Vives Y, Bulbena A, Tobeña A, Casas M, Vilarroya O. Laminar thickness alterations in the fronto-parietal cortical mantle of patients with attention-deficit/hyperactivity disorder. PLoS One. 2012;7(12):e48286