Shugao Xia, Abstract Co-Author: Nothing to Disclose

Ariane E. Kimball, Abstract Co-Author: Nothing to Disclose

Craig A. Branch PhD, Abstract Co-Author: Nothing to Disclose

Xiaobo Li, Presenter: Nothing to Disclose

Attention deficit/hyperactivity disorder (ADHD) has been associated with a deficit in working memory. Functional brain imaging studies have revealed evidence for alternations in the prefrontal cortex associated with working memory. The current study examined whether or not impairments in brain activation and function connectivity were detectable during a visual attention working memory task.

Participants were 20 children (age:10.8 ± 2.1) with ADHD and 15 healthy children (age: 12.5 ± 2.3). Brain activation and post-hoc functional connectivity were assessed with Functional magnetic resonance imaging (fMRI) scans while performing the visual attention working memory task.

Group analysis revealed significantly reduced activity in children with ADHD compared to controls in precentral gyrus bilaterally [L: (-50, -6, 28), BA 4; R: (48, -12, 12), BA 4 ] and significantly increased activity in left middle occipital cortex (MOC) [ (-28, -84, -14), BA 17 18 19]. Functional connectivity analysis of left MOC demonstrated significant decreases in functional connectivity with right prefrontal cortex [(-24, -84, 2), BA 9 10 11], left middle temporal cortex [(-58, -6, -8), BA 21], Ligual gyrus [(-34, -24, 2), BA 18 19] in children with ADHD, whereas significant decreases in functional connectivity were detected in the right medial frontal cortex [(-4, -4, 52), BA 6].

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.

fMRI can detect structural and functional deficits of cerebral cortex and is recommended as initial evaluation of  ADHD patients

Xia, S, Kimball, A, Branch, C, Li, X, Disturbed Brain Activity and Functional Connectivity during Visual Attention Working Memory Task in Attention Deficit/Hyperactivity Disorder.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11016070.html