A review of fronto-striatal and fronto-cortical brain abnormalities in children and adults with Attention Deficit Hyperactivity Disorder (ADHD) and new evidence for dysfunction in adults with ADHD during motivation and attention

Department of Child Psychiatry, Institute of Psychiatry, King's College London, UK.
Cortex (Impact Factor: 6.04). 04/2011; 48(2):194-215. DOI: 10.1016/j.cortex.2011.04.007
Source: PubMed

ABSTRACT Attention Deficit Hyperactivity Disorder (ADHD) has long been associated with abnormalities in frontal brain regions. In this paper we review the current structural and functional imaging evidence for abnormalities in children and adults with ADHD in fronto-striatal, fronto-parieto-temporal, fronto-cerebellar and fronto-limbic regions and networks. While the imaging studies in children with ADHD are more numerous and consistent, an increasing number of studies suggests that these structural and functional abnormalities in fronto-cortical and fronto-subcortical networks persist into adulthood, despite a relative symptomatic improvement in the adult form of the disorder. We furthermore present new data that support the notion of a persistence of neurofunctional deficits in adults with ADHD during attention and motivation functions. We show that a group of medication-naïve young adults with ADHD behaviours who were followed up 20 years from a childhood ADHD diagnosis show dysfunctions in lateral fronto-striato-parietal regions relative to controls during sustained attention, as well as in ventromedial orbitofrontal regions during reward, suggesting dysfunctions in cognitive-attentional as well as motivational neural networks. The lateral fronto-striatal deficit findings, furthermore, were strikingly similar to those we have previously observed in children with ADHD during the same task, reinforcing the notion of persistence of fronto-striatal dysfunctions in adult ADHD. The ventromedial orbitofrontal deficits, however, were associated with comorbid conduct disorder (CD), highlighting the potential confound of comorbid antisocial conditions on paralimbic brain deficits in ADHD. Our review supported by the new data therefore suggest that both adult and childhood ADHD are associated with brain abnormalities in fronto-cortical and fronto-subcortical systems that mediate the control of cognition and motivation. The brain deficits in ADHD therefore appear to be multi-systemic and to persist throughout the lifespan.

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Available from: Ana Cubillo, Oct 22, 2014
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    • "It has many connections to different areas of the brain. Research on the brain function of people with ADD has shown that frontal lobe dysfunction may cause the appearance of ADD symptoms [18]. The frontal cortex has an important role in controlling attention level, focusing, restraint, and patience. "
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    • "Another significant predictor of ADHD persistence was oppositional defiant disorder diagnosis, extending to adulthood a reported predictor of persistence from childhood studies (Barkley et al. 2008; Lara et al. 2009; Biederman et al. 2011; Riddle et al. 2013). This represents further evidence to a long lasting influence of oppositional defiant disorder in ADHD persistence and it is in line with data indicating that different circuitries may be dysfunctional in patients with ADHD that also present emotional dysregulation/irritability (Cubillo et al. 2012). Such Fig. 1. "
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    • "However, as in children, there is also evidence for widespread executive impairments [Biederman et al., 2011; Boonstra et al., 2005; Hervey et al., 2004; McLean et al., 2004] consistent with the notion that inhibitory deficits may exist as part of a more general pattern of executive dysfunction [Nigg, 2001]. Similarly, neuroimaging evidence in adult ADHD suggests functional abnormalities in a range of executive functions including response inhibition , working memory and task switching [Cortese et al., 2012; Cubillo et al., 2012]. However results are mixed, with adult patients showing reduced, increased or no difference in activation in fronto-striatal substrates during task performance [Carmona et al., 2012; Cubillo et al., 2010; Dibbets et al., 2009, 2010; Dillo et al., 2010; Epstein et al., 2007; Kooistra et al., 2010; Mulligan et al., 2011]. "
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