TY - JOUR
T1 - Executive and intellectual functions in attention-deficit/hyperactivity disorder with and without comorbidity
AU - Trani, Michela Di
AU - Casini, Maria Pia
AU - Capuzzo, Francesca
AU - Gentile, Simonetta
AU - Bianco, Giuseppe
AU - Menghini, Deny
AU - Vicari, Stefano
PY - 2011/6
Y1 - 2011/6
N2 - Background: Recent neuropsychological theories have targeted deficient executive functions (EF) as the main characteristic of Attention Deficit Hyperactivity Disorder (ADHD), but the nature of the neuropsychological deficits remains elusive and findings are heterogeneous. In particular, it is still unclear whether ADHD subtypes and comorbidity affect intellectual and executive functioning, because large variability has been found in different patient populations. Furthermore, the role of IQ in EF deficits in individuals with ADHD has been debated. Methods: The aim of the present research was to study in detail the relationship between EF, ADHD subtypes, and comorbid diagnosis by taking into account the potential role of IQ. For this purpose, 23 children (aged from 5 to 16. years; 20 males and 3 females) with a diagnosis of ADHD were selected. Results: Data show no differences between children with different subtypes of ADHD on measures of EF, but they evidence differences on EF measures in children with different comorbidities (internalizing versus externalizing disorder). Namely, compared to the internalizing disorders group, the children with externalizing disorders obtained significantly lower scores on different measures of EF (i.e., verbal working memory and categorical fluency), but these differences were strictly dependent on IQ level. Conclusions: Comorbidity patterns, rather than ADHD subtypes, appear to be more valid for defining the neuropsychological features of the ADHD endophenotype. Moreover, general intelligence seems to play a substantial role in the cognitive processes underling the disorder, especially in relation to externalizing aspects.
AB - Background: Recent neuropsychological theories have targeted deficient executive functions (EF) as the main characteristic of Attention Deficit Hyperactivity Disorder (ADHD), but the nature of the neuropsychological deficits remains elusive and findings are heterogeneous. In particular, it is still unclear whether ADHD subtypes and comorbidity affect intellectual and executive functioning, because large variability has been found in different patient populations. Furthermore, the role of IQ in EF deficits in individuals with ADHD has been debated. Methods: The aim of the present research was to study in detail the relationship between EF, ADHD subtypes, and comorbid diagnosis by taking into account the potential role of IQ. For this purpose, 23 children (aged from 5 to 16. years; 20 males and 3 females) with a diagnosis of ADHD were selected. Results: Data show no differences between children with different subtypes of ADHD on measures of EF, but they evidence differences on EF measures in children with different comorbidities (internalizing versus externalizing disorder). Namely, compared to the internalizing disorders group, the children with externalizing disorders obtained significantly lower scores on different measures of EF (i.e., verbal working memory and categorical fluency), but these differences were strictly dependent on IQ level. Conclusions: Comorbidity patterns, rather than ADHD subtypes, appear to be more valid for defining the neuropsychological features of the ADHD endophenotype. Moreover, general intelligence seems to play a substantial role in the cognitive processes underling the disorder, especially in relation to externalizing aspects.
KW - ADHD
KW - Comorbid diagnosis
KW - Executive function
KW - Intelligence quotient
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U2 - 10.1016/j.braindev.2010.06.002
DO - 10.1016/j.braindev.2010.06.002
M3 - Article
C2 - 20692779
AN - SCOPUS:79955883454
VL - 33
SP - 462
EP - 469
JO - Brain and Development
JF - Brain and Development
SN - 0387-7604
IS - 6
ER -