Possible Biomarker for ADHD
Research presented at the annual meeting of the Radiological Society of North America (RSNA) has identified abnormalities in the brains of children with attention deficit/hyperactivity disorder (ADHD) that may serve as a biomarker for the disorder.
Using functional magnetic resonance imaging (fMRI), researchers studied 18 typically developing children and 18 children diagnosed with ADHD (age range 9 to 15 years). While undergoing fMRI, the children engaged in a test of sustained attention in which they were shown a set of three numbers and then asked whether subsequent groups of numbers matched the original set. For each participant, fMRI produced a brain activation map that revealed which regions of the brain became activated while the child performed the task. The researchers then compared the brain activation maps of the two groups.
Compared to the normal control group, the children with ADHD showed abnormal functional activity in several regions of the brain involved in the processing of visual attention information. The researchers also found that communication among the brain regions within this visual attention-processing pathway was disrupted in the children with ADHD.
According to the authors, this tells us is that children with ADHD are using partially different functional brain pathways to process this information, which may be caused by impaired white matter pathways involved in visual attention information processing. “Much of the research conducted on ADHD has focused on the impulsivity component of the disorder however, inattention is an equally important component of this disorder and our findings contribute to understanding the pathology of inattentiveness in ADHD.”