Biomedical subjects

Jaap Oosterlaan

Publications and source records attributed to Jaap Oosterlaan.

31 records · Page 2Linked to original sources

PubMed2005

Towards an understanding of unique and shared pathways in the psychopathophysiology of ADHD.

Most attention deficit hyperactivity disorder (ADHD) research has compared cases with unaffected controls. This has led to many associations, but uncertainties about their specificity to ADHD in contrast with other disorders. We present a selective review of research, comparing ADHD with other disorders in neuropsychological, neurobiological and genetic correlates. So far, a specific pathophysiological pathway has not been identified. ADHD is probably not specifically associated with executive function deficits. It is possible, but not yet established, that ADHD symptoms may be more specifically associated with motivational abnormalities, motor organization and time perception. Recent findings indicating common genetic liabilities of ADHD and other conditions raise questions about diagnostic boundaries. In future research, the delineation of the pathophysiological mechanisms of ADHD needs to match cognitive, imaging and genetic techniques to the challenge of defining more homogenous clinical groups; multi-site collaborative projects are needed.

Attention Deficit Disorder with Hyperactivity↗

PubMed2005

The Stroop revisited: a meta-analysis of interference control in AD/HD.

BACKGROUND: An inhibition deficit, including poor interference control, has been implicated as one of the core deficits in AD/HD. Interference control is clinically measured by the Stroop Colour-Word Task. The aim of this meta-analysis was to investigate the strength of an interference deficit in AD/HD as measured by the Stroop Colour-Word Task and to assess the role of moderating variables that could explain the results. These moderating variables included: methods of calculating the interference score, comorbid reading and psychiatric disorders, AD/HD-subtypes, gender, age, intellectual functioning, medication, and sample size. METHODS: Seventeen independent studies were located including 1395 children, adolescents, and young adults, in the age range of 6-27 years. A meta-analysis was conducted to assess the effect sizes for the scores on the word and the colour card as well as the interference score. RESULTS: Children with AD/HD performed more poorly on all three dependent variables. The effect sizes for word reading (d=.49) and colour naming (d=.58) were larger and more homogeneous than the effect size for the interference score (d=.35). The method used to calculate the interference score strongly influenced the findings for this measure. When interference control was calculated as the difference between the score on the colour card minus the score on the colour-word card, no differences were found between AD/HD groups and normal control groups. DISCUSSION: The Stroop Colour-Word Task, in standard form, does not provide strong evidence for a deficit in interference control in AD/HD. However, the Stroop Colour-Word Task may not be a valid measure of interference control in AD/HD and alternative methodologies may be needed to test this aspect of the inhibitory deficit model in AD/HD.

Adolescent↗

PubMed2004

The impact of reinforcement contingencies on AD/HD: a review and theoretical appraisal.

One of the core deficits in attention deficit/hyperactivity disorder (AD/HD) is thought to be an aberrant sensitivity to reinforcement, such as reward and response cost. Twenty-two studies (N=1181 children) employing AD/HD and reinforcement contingencies are reviewed from vantage points: task performance, motivation, and psychophysiology. Results indicate that reinforcement contingencies have a positive impact on task performance and levels of motivation for both children with AD/HD and normal controls. There is evidence that the effect related to task performance is somewhat more prominent in AD/HD. There is some evidence that a high intensity of reinforcement is highly effective in AD/HD. Children with AD/HD prefer immediate over delayed reward. From a psychophysiological point of view, children with AD/HD seem less sensitive to reinforcement compared to controls. While comorbid disorders are suggested to be confounders of the dependent variables, many studies do not examine the effect of oppositional defiant disorder (ODD) and conduct disorder (CD). We discuss the implications of the findings for five theoretical frameworks, including the model by, the cognitive-energetic model (CEM), the dual-pathway model and the BIS/BAS model. Results show a discrepancy between the theoretical models and the behavioural findings.

Antisocial Personality Disorder↗

PubMed2004

ADHD subtypes: do they differ in their executive functioning profile?

The present study was designed to investigate the hypothesis that children with Attention Deficit Hyperactivity Disorder combined subtype (ADHD-C) have a generalized executive functioning (EF) [Barkley, R. A. (1997). Behavioural inhibition, sustained attention, and executive functions: Constructing a unifying theory of AD/HD. Psychological Bulletin, 121, 65-94; Barkley, R. A. (1997). ADHD and the nature of self-control. New York: The Guilford Press]. We tested whether ADHD-C and ADHD inattentive subtype (ADHD-I) can be differentiated from each other on EF measures. We compared 16 normally developing boys with 16 boys with ADHD-C and 16 with ADHD-I on five EF domains. The boys were all matched on age, IQ, and the presence of oppositional defiant disorder (ODD)/conduct disorder (CD). Despite carefully diagnosed groups and methodological controls, the results do not support the EF-hypothesis of ADHD-C. Children with ADHD-C differed from normal controls (NC) on tasks related to inhibition; they did not exhibit EF deficits on all EF tasks. Children with ADHD-C also exhibited deficits on non-EF tasks. Furthermore, the ADHD-C and ADHD-I subtypes did not differ from one another. Neuropsychological findings on the domains under study did not yield evidence for the distinctiveness of ADHD-C and ADHD-I subtypes.

Adolescent↗

PubMed2004

High antenatal maternal anxiety is related to impulsivity during performance on cognitive tasks in 14- and 15-year-olds.

This study prospectively investigated the influence of antenatal maternal anxiety, measured with the State Trait Anxiety Inventory at 12-22, 23-31 and 32-40 postmenstrual weeks of pregnancy, on cognitive functioning in 57 adolescents (mean age 15 years). ANCOVAs showed effects of State anxiety at 12-22 weeks, after controlling for influences of State anxiety in later pregnancy and postnatal maternal Trait anxiety. Adolescents of high anxious pregnant women reacted impulsively in the Encoding task; they responded faster but made more errors than adolescents of low anxious women. They also scored lower on two administered WISC-R subtests. In the Stop task no differences in inhibiting ongoing responses were found between adolescents of high and low anxious pregnant women. We suspect that high maternal anxiety in the first half of pregnancy may negatively affect brain development of the fetus, reflected by impulsivity and lower WISC-R scores at 14-15 years.

Adolescent↗

PubMed2004

Executive functioning in boys with ADHD: primarily an inhibition deficit?

This study was aimed at: (1) testing whether boys with Attention Deficit/Hyperactivity Disorder (ADHD) demonstrate a deficit in response inhibition and deficits in other executive functions (EF), or alternatively, demonstrate a deficit in only response inhibition; (2) investigating which role associated factors, such as IQ, age, and performance on non-EF tasks play in EF in ADHD; (3) studying the association between the three different forms of inhibition studied here. Boys with ADHD were compared with normal control (NC) boys on five domains of executive functioning: inhibition (inhibition of a prepotent response, inhibition of an ongoing response, and interference control), planning, set-shifting, working memory, and verbal fluency. Boys with ADHD demonstrated deficits in interference control, inhibition of an ongoing response, planning, and letter fluency. After controlling for age, IQ, and non-EF measures, none of the EF deficits in ADHD remained. Finally, correlations between different inhibition measures were generally low, and correlations within domains of inhibition were not higher than correlations between domains of inhibition. This calls into question the distinctiveness of the different forms of response inhibition.

Age Factors↗

PubMed2004

Pathological gambling: a comprehensive review of biobehavioral findings.

In this review, findings of biobehavioral research into pathological gambling (PG) are discussed, focusing on neuropsychological, psychophysiological, neuroimaging, neurochemical and genetic studies. Neuropsychological studies indicate deficiencies in certain executive functions. Psychophysiological studies indicate that arousal in PG is of importance when reward is present. Neuroimaging studies point to abnormalities in brain functioning. Recent research into the neurochemistry of PG indicates that abnormalities exist in different neurotransmitter systems. Finally, genetic studies indicate the existence of abnormal dopamine receptor genes in PG. Methodological and theoretical factors that may explain discrepancies between studies include differences in screening and assessment, heterogeneity of gambling problems and different underlying cognitive or motivational mechanisms. Results from the PG studies fit in with recent theoretical models of addiction and PG, which stress the involvement of brain reward pathways, neurotransmitter abnormalities, the frontal cortex and the psychophysiological stress system. A framework for future studies is suggested, indicating the need for studies that integrate knowledge from different research areas, and that employ stricter diagnostic screening methods and inclusion of clinical control groups.

Behavior, Addictive↗

PubMed2004

How specific are executive functioning deficits in attention deficit hyperactivity disorder and autism?

BACKGROUND: The objective of this study is to identify intact and deficient cognitive processes in children with attention deficit hyperactivity disorder (ADHD) and children with high functioning autism (HFA). METHOD: Three rigorously diagnosed groups of children aged between 6 and 12 years (54 ADHD, 41 HFA, and 41 normal controls) were tested on a wide range of tasks related to five major domains of executive functioning (EF): inhibition, visual working memory, planning, cognitive flexibility, and verbal fluency. In addition, the role of comorbid oppositional defiant disorder (ODD) and comorbid conduct disorder (CD) in ADHD was investigated by directly comparing 20 children with ADHD and 34 children with comorbid ADHD + ODD/CD. RESULTS: ADHD was associated with EF deficits in inhibiting a prepotent response and verbal fluency. Children with HFA demonstrated deficits in all EF domains, except interference control and working memory. The HFA group showed more difficulties than the ADHD group with planning and cognitive flexibility. The comorbid ADHD + ODD/CD group did not show a distinctive pattern of performance on the EF tests compared to the ADHD group. CONCLUSION: The present study indicates that children with HFA exhibit more generalised and profound problems with EF tasks compared to children with ADHD.

Attention Deficit Disorder with Hyperactivity↗

PubMed2004

Can the Children's Communication Checklist differentiate between children with autism, children with ADHD, and normal controls?

BACKGROUND: The Children's Communication Checklist (CCC; Bishop, 1998) is a questionnaire that was developed to measure pragmatic language use and may be completed by parents and teachers. Two studies are reported, which were designed to investigate: (1) whether children with Attention Deficit Hyperactivity Disorder (ADHD) encounter pragmatic language problems in comparison with normal controls (NC), (2) whether children with ADHD and children with High Functioning Autism (HFA) can be differentiated using the CCC, (3) the usefulness of the CCC for parents and teachers in a clinical and in a research setting, and (4) the role of age in pragmatic language use in ADHD and HFA. METHOD: In the first study (clinical sample) 50 children with ADHD, 50 children with HFA, and 50 NC were compared to each other using the CCC. In the second study (research sample) CCC data was gathered on 23 children with ADHD (without co-morbid disorders), 42 children with HFA, and 35 NC. RESULTS: Compared to NC, children with HFA showed pragmatic deficits on all CCC scales. Children with ADHD demonstrated deficits compared to NC as well. Moreover, the ADHD and HFA groups differed from each other on most of the scales. Discriminant analyses showed that CCC scales were relevant for case identification in these samples. Furthermore, profiles of impairment seen in children with HFA and ADHD did not vary with age. CONCLUSION: Pragmatic difficulties do occur in both HFA and ADHD. The present studies indicate that the CCC is a useful instrument to obtain information concerning pragmatic language use in both a clinical and a research setting. Although the information of parents is more tightly linked to the diagnosis, combining the information of both parent and teacher slightly improves case identification.

Adolescent↗

PubMed2003

The top and the bottom of ADHD: a neuropsychological perspective.

Five models of attention deficit/hyperactivity disorder (ADHD) are reviewed. It is proposed that the cognitive-energetic model provides a reasonably comprehensive account of ADHD by incorporating the features of both the inhibition and delay aversion models. It is suggested that ADHD can only be accounted for by an analysis at three levels: top-down control, specific cognitive processes and energetic factors. It is argued that a refined and conceptually comprehensive neuropsychological battery is needed to advance research in ADHD. A widely distributed neural network involving frontal, basal ganglia, limbic and cerebellar loci seem implicated in ADHD.

Attention Deficit Disorder with Hyperactivity↗

PubMed2003

The effect of methylphenidate on three forms of response inhibition in boys with AD/HD.

The current study was aimed at (a) investigating the effect of three doses methylphenidate (MPH) and placebo on inhibition of a prepotent response, inhibition of an ongoing response, and interference control in Attention Deficit/Hyperactivity Disorder (AD/HD), and (b) studying dose-response relations for the three forms of response inhibition. To meet these aims, the following tasks were selected: two versions of the Stop Paradigm for inhibition of a prepotent response, a Circle Tracing Task and a recently developed Follow Task for inhibition of an ongoing response, and the Stroop Color-Word Test and an Eriksen Flanker Task for interference control. These tasks were administered to 23 boys with AD/HD during four treatment conditions: 5 mg MPH, 10 mg MPH, 20 mg MPH, and placebo. A pseudorandomized, multiple-blind, placebo-controlled, within-subject design was used. As hypothesized, inhibitory control in children with AD/HD improved under MPH compared to placebo. However, this effect was only significant for inhibition of a prepotent response and inhibition of an ongoing response (as measured by the Follow Task), but not for interference control. The relation between treatment condition and response was linear. However, this linear relation was due to improved inhibitory control under MPH compared to placebo, because no effects of MPH dose were observed for any of the response inhibition measures.

Attention↗

PubMed2002

How specific is a deficit of executive functioning for attention-deficit/hyperactivity disorder?

A selective review of research in the executive functioning (EF) is given for attention deficit hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), conduct disorder (CD), higher functioning autism (HFA) and Tourette syndrome. The review is restricted due to changes in the classification of the disorder in recent years and secondly the heterogeneity of EF is restricted to five key areas of concern, inhibition, set shifting, working memory, planning, and fluency. The review makes clear that there are strong differences between child psychopathological groups and controls on these EFs. However, future research will be needed to identify an EF deficit or profile, which is specific for these disorders.

Adolescent↗

PubMedDate not supplied

Emotion regulation and the dynamics of feelings: a conceptual and methodological framework.

The emotional system is defined as a dynamical system that has neurological and biochemical structures that force the system to change in a regular and consistent way. This dynamic view allows for an alternative definition of emotion regulation, which describes when emotion regulation is needed, identifies its goal, and illustrates how regulation is achieved. The thesis developed here is that feelings-the private mental experience of emotion-play a crucial role in emotion regulation. Specifics of regulation are discussed and a parallel with parent-child interaction is drawn. It is shown that emotion regulation can be studied by looking at the variability of feelings. An illustrative application (N=30, age 10-13 years) shows that variability of anger is associated with the core executive function response inhibition.

Adolescent↗