Differential Brain Activation Patterns in Adult Attention-Deficit Hyperactivity Disorder (ADHD) Associated With Task Switching

Department of Clinical Psychological Science, Faculty of Psychology and Neuroscience, Maastricht University, the Netherlands.
Neuropsychology (Impact Factor: 3.27). 07/2010; 24(4):413-23. DOI: 10.1037/a0018997
Source: PubMed


The main aim of the study was to examine blood oxygen level-dependent response during task switching in adults with attention-deficit/hyperactivity disorder (ADHD).
Fifteen male adults with ADHD and 14 controls participated and performed a task-switching paradigm.
Behaviorally, no specific executive control problems were observed in the ADHD participants, although they did display more errors in general. The neuroimaging data did show remarkable differences between the ADHD and control adults: Adults with ADHD engaged more strongly the dorsal anterior cingulate cortex, middle temporal gyrus, precuneus, lingual gyrus, precentral gyrus, and insula than did the healthy controls during task switching. Controls displayed more task-related activity in the putamen, posterior cingulate gyrus, medial frontal gyrus, thalamus, orbitofrontal cortex, and postcentral gyrus.
ADHD adults did not display specific executive control problems at a behavioral level, but did engage different brain areas during task switching compared with healthy controls. The results are discussed in the framework of the executive frontostriatal circuitry, conflict detection, and attentional networks.

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Available from: Pauline Dibbets, Dec 19, 2013
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    • "Of the studies that have been conducted, several have shown decreased activation as well as functional connectivity in frontostriatal, frontocerebellar and frontoparietal networks (Bush et al. 1999, Valera et al. 2005, Wolf et al. 2009). Conversely, there are other studies in adults that show increased activation throughout the frontal, parietal and occipital lobes during tasks of executive function (Hale et al. 2007, Banich et al. 2009, Dibbets et al. 2010). It has been hypothesized that inconsistencies across studies of adult ADHD, as compared to child/adolescent ADHD, may be due to confounding factors such as the need for retrospective diagnoses, medication effects, symptom remission and comorbid disorders (Cubillo and Rubia 2010). "
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    • "We did not find much evidence for attentional shifting abnormalities in ADHD in behavior or BOLD signal. Few studies have examined shifting or cognitive flexibility in adults, with two studies using traditional task switching paradigms reporting inconsistent results, possibly due to different comorbidity and medication status [Cubillo et al., 2010; Dibbets et al., 2010]. It is difficult to interpret the present findings within the context of these studies as task requirements were very different, with infrequent shifting requiring no change in overt responding [Dodds et al., 2011]. "
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