Functional MRI detects impaired brain activity, functional connectivity in children with ADHD
MONDAY, Nov. 28 (HealthDay News) -- Functional magnetic resonance imaging (fMRI) of the brains of children with attention-deficit/ hyperactivity disorder (ADHD) show disturbances in the functional connectivity between the visual sensory cortex and the prefrontal cortex, according to a study presented at the annual meeting of the Radiological Society of North America, held from Nov. 27 to Dec 2 in Chicago.
Xiaobo Li, Ph.D., from the Albert Einstein College of Medicine in New York City, and colleagues investigated whether impairments in brain activation and functional connectivity are detectable in children with ADHD during a visual attention working-memory task. In total, 20 children (age, 10.8 ± 2.1 years) with ADHD and 15 healthy children (age, 12.5 ± 2.3 years) underwent fMRI while engaged in a visual attention working-memory task.
The investigators found that, in a group analysis, children with ADHD had significantly reduced activity in the precentral gyrus bilaterally, and significantly increased activity in the left middle occipital cortex (MOC), compared to controls. Functional connectivity analysis of the left MOC revealed that children with ADHD had a significant reduction in the functional connectivity with the right prefrontal cortex, left middle temporal cortex, and lingual gyrus. Functional connectivity in the right medial frontal cortex was significantly reduced.
"Our results, while preliminary, demonstrate that disturbances exist in functional connectivity between the visual sensory cortex and the prefrontal cortex in children with ADHD. This finding may underlay deficits in working memory in the absence of visual sensory stimuli in ADHD," the authors write.