Heterogeneity in hyperkinetic disorder
type: CreativeWork
description: It is increasingly recognised that the broadly defined behavioural phenotype of attention deficit – hyperactivity disorder (ADHD) is a heterogeneous condition and that this heterogeneity is seen across all levels of analysis from the genetic and environmental causes to the associated neuropsychological deficits, the clinical presentation and response to treatment. This work investigated whether the more restrictive and clinically homogeneous hyperkinetic disorder (HKD) phenotype is associated with reduced neuropsychological heterogeneity compared with the broader ADHD phenotype. Using a well known, broad based battery of neuropsychological tasks from the Cambridge Neuropsychological Test Automated Battery (CANTAB) and a computerised Go/NoGo task in a large well described group of boys with rigorously diagnosed HKD who were stimulant medication naïve at baseline, it was demonstrated that the neuropsychological heterogeneity in the HKD boys was very similar to that seen previously in children with ADHD. Interestingly, and contrary to popular opinion, the strongest associations were with more simple recognition memory tasks with a low executive demand. Although there were significant associations between HKD and deficits on a range of tasks with high executive demands these were less strong. Could this neuropsychological heterogeneity be a function of different developmental issues or comorbidity? With respect to development there was evidence that boys with HKD lagged behind the healthy boys with respect to the development of their neuropsychological performance. However the pattern of development was similar with the performance of the HKD boys paralleling that of the healthy boys, suggesting that the neuropsychological heterogeneity seen in HKD is not accounted for by developmental issues. With respect to the relationship between neuropsychological functioning and comorbidity, the impact of comorbid oppositional defiant disorder (ODD) and conductdisorder (CD), it wa…
abstract: It is increasingly recognised that the broadly defined behavioural phenotype of attention deficit – hyperactivity disorder (ADHD) is a heterogeneous condition and that this heterogeneity is seen across all levels of analysis from the genetic and environmental causes to the associated neuropsychological deficits, the clinical presentation and response to treatment. This work investigated whether the more restrictive and clinically homogeneous hyperkinetic disorder (HKD) phenotype is associated with reduced neuropsychological heterogeneity compared with the broader ADHD phenotype. Using a well known, broad based battery of neuropsychological tasks from the Cambridge Neuropsychological Test Automated Battery (CANTAB) and a computerised Go/NoGo task in a large well described group of boys with rigorously diagnosed HKD who were stimulant medication naïve at baseline, it was demonstrated that the neuropsychological heterogeneity in the HKD boys was very similar to that seen previously in children with ADHD. Interestingly, and contrary to popular opinion, the strongest associations were with more simple recognition memory tasks with a low executive demand. Although there were significant associations between HKD and deficits on a range of tasks with high executive demands these were less strong. Could this neuropsychological heterogeneity be a function of different developmental issues or comorbidity? With respect to development there was evidence that boys with HKD lagged behind the healthy boys with respect to the development of their neuropsychological performance. However the pattern of development was similar with the performance of the HKD boys paralleling that of the healthy boys, suggesting that the neuropsychological heterogeneity seen in HKD is not accounted for by developmental issues. With respect to the relationship between neuropsychological functioning and comorbidity, the impact of comorbid oppositional defiant disorder (ODD) and conductdisorder (CD), it wa…
author: Coghill, David Rockwell
language: eng
keywords: ADHD, Methylphenidate, Neuropsychology, Hyperkinetic, Stimulant, Attention deficit hyperactivity disorder (ADHD)
date published: 2010
date modified: 2026-07-24T02:07:31Z
provider: University of Dundee
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Dundee