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: 5.13). 04/2011; 48(2):194-215. DOI: 10.1016/j.cortex.2011.04.007
Source: PubMed


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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    • "neuroimaging level atypical lateralized brain activity has been found in many studies during rest , simple or complex task performance ( Sieg et al . , 1995 ; Chabot and Serfontein , 1996 ; Ernst et al . , 1998 ; Baving et al . , 1999 ; Tamm et al . , 2006 ; Hale et al . , 2009 ; Cortese et al . , 2012 ; Cubillo et al . , 2012 ) . This might suggest that atypical laterality is present in ADHD , but had not reached a specific degree or threshold to affect dimensionally the behavioral performance ( e . g . , reaction time ) . The threshold might be reached if ADHD scores are close to the clinical cut - off ( 65 or higher ) . Evidence in favor of this suggestion"
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    • "This enables the OFC to serve as a specialized short term memory buffer, monitoring which recent actions were rewarded and predicting which future actions are most likely to be rewarded (Kahnt et al., 2010). Individuals with ADHD show relatively low sensitivity to reward related information as compared with NC, evident in lower neural activity levels in the ventral striatum (Ströhle et al., 2008), and poor OFC responsiveness to reward (Cubillo et al., 2012; Wilbertz et al., 2012). The anterior insula plays a critical role in mediating between the ventral and dorsal executive networks (primarily in the right hemisphere), and it exhibits significant functional connectivity to dorsal prefrontal brain regions involved in goal-directed behavior (Eckert et al., 2009). "
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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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