Biomedical subjects

H Roeyers

Publications and source records attributed to H Roeyers.

14 recordsLinked to original sources

PubMed2006

The analysis of 51 genes in DSM-IV combined type attention deficit hyperactivity disorder: association signals in DRD4, DAT1 and 16 other genes.

Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder, starting in early childhood and persisting into adulthood in the majority of cases. Family and twin studies have demonstrated the importance of genetic factors and candidate gene association studies have identified several loci that exert small but significant effects on ADHD. To provide further clarification of reported associations and identify novel associated genes, we examined 1,038 single-nucleotide polymorphisms (SNPs) spanning 51 candidate genes involved in the regulation of neurotransmitter pathways, particularly dopamine, norepinephrine and serotonin pathways, in addition to circadian rhythm genes. Analysis used within family tests of association in a sample of 776 DSM-IV ADHD combined type cases ascertained for the International Multi-centre ADHD Gene project. We found nominal significance with one or more SNPs in 18 genes, including the two most replicated findings in the literature: DRD4 and DAT1. Gene-wide tests, adjusted for the number of SNPs analysed in each gene, identified associations with TPH2, ARRB2, SYP, DAT1, ADRB2, HES1, MAOA and PNMT. Further studies will be needed to confirm or refute the observed associations and their generalisability to other samples.

Adolescent↗

PubMed2006

Satisfaction with formal support and education for children with autism spectrum disorder: the voices of the parents.

INTRODUCTION: The aim of the present study was to identify and describe factors associated with variations in the level of parental satisfaction with formal support and education for children with autism spectrum disorder (ASD) in Flanders. METHODS: Participants were recruited by a mailing from a diagnostic centre for pre-schoolers and by advertisements dispersed in the Flemish parent organization for ASD and in services and special schools. The sample consisted of 244 parents of children with ASD (age range: 2.69-17.81 years, male/female sex ratio 4:1). The data were collected using a questionnaire on experiences with education and support, which was compiled for the purpose of this study. The data resulting from the questionnaire were supplemented with information obtained from semi-structured in-depth interviews with a stratified sample of 15 parents. RESULTS AND CONCLUSIONS: The study revealed that parents experienced difficulties with the diagnostic process, with support and education provided by mainstream settings and with the accessibility of autism-specific service provisions. Conversely, parents reported to be satisfied with the quality of autism-specific support and education. Predictors of overall satisfaction were parental involvement in formal support, knowledge of available service provisions and time between first consultation and final diagnosis. Practical implications of the results are discussed.

Adolescent↗

PubMed2005

ERP correlates of impaired error monitoring in children with ADHD.

OBJECTIVE: The purpose of the current study was to elaborate on error monitoring in children with Attention Deficit Hyperactivity Disorder (ADHD) using the ERP methodology. METHOD: Children with ADHD executed a visual Go/No-Go task with 25 percent No-Go trials; and a two stimulus reaction time task wherein a neutral warning signal (S1) was presented to inform the child to prepare for an imperative stimulus (S2). RESULTS: In both tasks, children with ADHD responded as fast as controls but made twice as many errors. In addition, they failed to adjust their speed of responding after making an error. Exploring the error-related potentials revealed that the error-related negativity (ERN) was the same for the two groups, but that children with ADHD showed a diminished error positivity (Pe). CONCLUSIONS: Based on these findings, we conclude that children with ADHD are normal in early error monitoring processes related to error detection, but show abnormal response strategy adjustments and are deviant in later error monitoring processes associated with the subjective/emotional, conscious evaluation of the error.

Adolescent↗

PubMed2005

State regulation and response inhibition in children with ADHD and children with early- and continuously treated phenylketonuria: an event-related potential comparison.

BACKGROUND: The presentation rate of stimuli plays an important role in explaining the performance inefficiency in children with ADHD. In general, children with ADHD have been found to perform more poorly in conditions of relatively slow event rates as compared with fast and moderate event rates. The state regulation hypothesis states that these children have problems in correcting their energetic state necessary to counteract a performance decrement, which requires extra effort allocation. In this study, we investigated state regulation in children with ADHD and used children with early- and continuously treated phenylketonuria (PKU) as a clinical contrast group. METHOD: We measured the parietal P3 during a Go/No-Go task that incorporated a condition with a fast and a slow presentation rate. RESULTS: We were able to show that children with ADHD, relative to controls, responded more slowly and more variably in the slow condition only, which was accompanied by a smaller P3, suggesting less effort allocation. In contrast, the children with PKU did not show a state regulation deficit. The PKU group showed prolonged stimulus evaluation processing, as indexed by P3 latency, compared to controls and children with ADHD. In addition, they made more errors of commission than the controls and the ADHD group. CONCLUSIONS: Our electrophysiological data support the state regulation hypothesis of ADHD. Only the children with PKU had more problems in inhibiting pre-potent responding than controls, which is in accord with the prefrontal dysfunction hypothesis of PKU.

Attention Deficit Disorder with Hyperactivity↗

PubMed2003

Behavioural problems, social competence and self-concept in siblings of children with autism.

INTRODUCTION: This study investigated the psychological adjustment of siblings of children with high-functioning autism (HFA) in comparison with siblings of normally developing children in the domain of behavioural problems, social competence and self-concept. METHOD: Twenty-nine siblings of children with HFA and 29 siblings of children without a disorder participated in the study. Standardized, written questionnaires were used. RESULTS: Siblings of children with HFA, especially brothers and sisters between 6 and 11 years old, had more behavioural problems than siblings of the control group. Sisters of children with HFA ascribed higher social competence to themselves. Sisters of children with HFA between 12 and 16 years old had a more positive self-concept. In both groups siblings with a more negative self-concept had less social skills and siblings with a more positive self-concept scored better in the social domain. Finally, in accordance with the control group, the perception of the siblings' social competence of parents of children with HFA broadly matched the perception siblings had of themselves. DISCUSSION: Overall, siblings of children with HFA are not more susceptible to adaptation problems than siblings of children without a disorder. Implications for practice and further research are discussed.

Adaptation, Psychological↗

PubMed2001

VIDANN: a video annotation system.

VIDANN is a computer program that allows participants to watch a video on a standard TV and to write their annotations (thought/feeling entries) on paper attached to a writing tablet. The system is designed as a Microsoft ActiveX module. It can be further adapted by the individual researcher through the use of a VBScript. All data, including the participant's handwriting, are stored in an XML database. An accompanying Wizard has been designed that enables researchers to generate VBScripts for standard configurations.

Humans↗

PubMed2001

Advancing advanced mind-reading tests: empathic accuracy in adults with a pervasive developmental disorder.

Research using advanced but static mind-reading tests with high-functioning adults with a pervasive developmental disorder (PDD) provided evidence for subtle social cognitive deficits. In the present study, adults with PDD were unimpaired on such tasks, relative to individually matched normal controls. Significant differences between the two groups were, however, found on a more naturalistic empathic accuracy task developed for this study. Participants viewed two videotaped interactions that both depicted a male and female stranger having an initial conversation and were asked to infer the unexpressed thoughts and feelings of the four targets. Subjects with PDD performed significantly worse on the second video. These findings suggest that the mind-reading deficit of a subgroup of able adults with PDD may only be apparent when a sufficiently complex naturalistic assessment method is being used.

Adolescent↗

PubMed2000

EPA2000: a multilingual, programmable computer assessment of off-line metacognition in children with mathematical-learning disabilities.

EPA2000 is a program for the assessment of off-line measured metacognitive skills and arithmetical performances in primary school children with mathematical-learning disabilities. The program is designed as a script engine. The concept makes it possible to modify and translate the test into different languages without reprogramming. A user-friendly script editor is built-in, with which all of the parameters of the test can be modified and translated in different languages.

Child↗

PubMed2000

Stimulation seeking and hyperactivity in children with ADHD. Attention Deficit Hyperactivity Disorder.

Thirty hyperactive and 30 non-hyperactive children were confronted with a delay, consisting of a waiting situation of 15 minutes, either with or without extra stimulation provided by the presentation of a videotape. The behaviour of the child during the waiting period was videotaped and later coded by two naive observers. In line with theories that emphasise the stimulation-seeking function of hyperactive behaviours, such as the optimal stimulation account and the delay aversion theory, a group by stimulation effect was hypothesised. For two categories of activity this was found, with ADHD children displaying more activity than non-ADHD children in the no-stimulation but not in the stimulation condition. These data provide support for the stimulation-seeking function of certain features of ADHD hyperactivity.

Attention Deficit Disorder with Hyperactivity↗

PubMed1998

Immediate imitation and joint attention in young children with autism.

There is growing scientific interest in the precursors to the ability of conceiving other people's minds. The present study investigates two candidate precursors, imitation and joint attention, in young children with autism and a control group of nonautistic children with a developmental delay. Children with autism were found to be impaired or delayed in both abilities. Gestural and procedural imitation were significantly related to mental age and chronological age in subjects with autism. Although the evidence for an autism-specific deficit appears to be stronger in the domain of joint-attention behaviors than it is in the domain of imitation, it seems premature to reject imitation as a possible precursor to the development of mindreading skills. Systematic investigations of the imitation deficit in autism are urgently needed.

Attention↗

PubMed1996

The influence of nonhandicapped peers on the social interactions of children with a pervasive development disorder.

This study investigated whether or not children with autism or a related pervasive developmental disorder (PDD) can benefit from regular opportunities to interact with a normally developing peer, matched as to sex and age. An experimental design with random assignment of subjects to treatment and control groups was used to demonstrate the impact of this peer-mediated intervention. In the treatment group, we found significant improvements in the social behavior of the children with PDD. Several gains were also generalized to interactions with an unfamiliar nonhandicapped peer, to interactions with another child with PDD, and to the large school setting. In the untreated control group, no positive changes were observed. Results suggest that children with PDD can develop peer relations if appropriate social contexts are made available for them.

Adolescent↗

PubMed1995

Siblings of a child with autism, with mental retardation and with a normal development.

A total of 60 children between 8 and 15 years of age participated in this project, 20 of whom had a sibling with autism, 20 a sibling with mental retardation and 20 a non-disabled sibling. The children were questioned about their sibling relationship and their experiences of stress. The children with a sibling with autism also completed a questionnaire on their knowledge of the autistic syndrome. Analyses revealed that the three groups were basically similar in their ratings of the frequency of stressors involving their siblings. There was a trend for children with a disabled brother or sister to rate their relationship with the sibling more positively. Correlational analyses revealed an association between both stressor frequency and appraisal and the evaluation of the relationship with the brother or sister. Siblings of children with autism had a fair understanding of the autistic syndrome. In this group, there was also an association between the children's knowledge of the autistic disorder and the quality of the sibling relationship.

Adolescent↗

PubMedDate not supplied

Metacognition and mathematical problem solving in grade 3.

This article presents an overview of two studies that examined the relationship between metacognition and mathematical problem solving in 165 children with average intelligence in Grade 3 in order to help teachers and therapists gain a better understanding of contributors to successful mathematical performance. Principal components analysis on metacognition revealed that three metacognitive components (global metacognition, off-line metacognition, and attribution to effort) explained 66% to 67% of the common variance. The findings from these studies support the use of the assessment of off-line metacognition (essentially prediction and evaluation) to differentiate between average and above-average mathematical problem solvers and between students with a severe or moderate specific mathematics learning disability.

Awareness↗

PubMedDate not supplied

Differentiating attention-deficit/hyperactivity disorder from pervasive developmental disorder not otherwise specified.

This study investigated early clinical differences between children with a diagnosis of pervasive developmental disorder not otherwise specified (PDD-NOS) and children with attention-deficit/hyperactivity disorder (ADHD). Differential diagnoses between the two disorders is often difficult in infancy or early childhood. Twenty-seven children with PDD-NOS were matched with 27 children with ADHD as to IQ and chronological age. Their parents were retrospectively questioned on pre-, peri-, and postnatal complications and on atypical or delayed development of the children between 0 and 4 years of age. This exploratory study revealed almost no differences between both groups with respect to pregnancy or birth complications. The results suggest that differences between the two groups become more pronounced and specific with growing age. Consequently, this investigation offers sufficient guidelines for more specific research with larger samples.

Age Factors↗