This article presents a review of the studies that have analysed the motor skills of ADHD childre... more This article presents a review of the studies that have analysed the motor skills of ADHD children with without medication and the influence of medication on their motor skills. The following two questions guided the study: What is the evidence of impairment of motor skills and aspects of motor control among children with ADHD aged between 6 and 16 years? What are the effects of ADHD medication on motor skills and motor control?
The following keywords were introduced in the main databases: attention disorder and/or ADHD, motor skills and/or handwriting, children, medication. Of the 45 articles retrieved, 30 described motor skills of children with ADHD and 15 articles analysed the influence of ADHD medication on motor skills and motor control.
More than half of the children with ADHD have difficulties with gross and fine motor skills. The children with ADHD inattentive subtype seem to present more impairment of fine motor skills, slow reaction time, and online motor control during complex tasks. The proportion of children with ADHD who improved their motor skills to the normal range by using medication varied from 28% to 67% between studies. The children who still show motor deficit while on medication might meet the diagnostic criteria of developmental coordination disorder (DCD). It is important to assess motor skills among children with ADHD because of the risk of reduced participation in activities of daily living that require motor coordination and attention.
The aim of this paper is to discuss if criteria used for diagnosing children for clinical purpose... more The aim of this paper is to discuss if criteria used for diagnosing children for clinical purposes should be the same as for the selection of children with Developmental Coordination Disorder for research. Next, we give an overview of the criteria mentioned in the development of the European guideline for diagnosing Developmental Coordination Disorder and the implementation of this guideline in different countries. To gain insight into current clinical practice, we also reviewed the medical files of children attending rehabilitation centers for the criteria used to diagnose Developmental Coordination Disorder in the Netherlands. To conclude, we state our expert opinion on why and when research and clinical criteria for Developmental Coordination Disorder should or should not be the same.
Children with developmental coordination disorder (DCD) face evident motor difficulties in daily ... more Children with developmental coordination disorder (DCD) face evident motor difficulties in daily functioning. Little is known, however, about their difficulties in specific activities of daily living (ADL). The purposes of this study were: (1) to investigate differences between children with DCD and their peers with typical development for ADL performance, learning, and participation, and (2) to explore the predictive values of these aspects. This was a cross-sectional study. In both a clinical sample of children diagnosed with DCD (n=25 [21 male, 4 female], age range=5-8 years) and a group of peers with typical development (25 matched controls), the children's parents completed the DCDDaily-Q. Differences in scores between the groups were investigated using t tests for performance and participation and Pearson chi-square analysis for learning. Multiple regression analyses were performed to explore the predictive values of performance, learning, and participation. Compared with ...
Many clinical studies reported a compromised brain lateralization in patients with Attention-Defi... more Many clinical studies reported a compromised brain lateralization in patients with Attention-Deficit/Hyperactivity Disorder (ADHD) without being conclusive about whether the deficit existed in the left or right hemisphere. It is well-recognized that studying ADHD dimensionally is more controlled for comorbid problems and medication effects, and provides more accurate assessment of the symptoms. Therefore, the present study applied the dimensional approach to test the relationship between brain lateralization and self-reported ADHD symptoms in a population sample. Eighty-five right-handed university students filled in the Conners' Adult ADHD Rating Scales and performed a lateralization reaction time task. The task consists of two matching conditions: one condition requires nominal identification for letters tapping left hemisphere specialization (Letter Name-Identity condition) and the other one requires physical and visuospatial identification for shapes tapping right hemisphere...
Deze bijdrage betreft een handvoorkeurstest voor kinderen van 5 tot 7 jaar. Eerst wordt de ontwik... more Deze bijdrage betreft een handvoorkeurstest voor kinderen van 5 tot 7 jaar. Eerst wordt de ontwikkeling van handvoorkeur en het belang van de bepaling ervan kort besproken. Daarna worden aspecten van de betrouwbaarheid en validiteit besproken aan de hand van testgegevens van 67 kinderen van gemiddeld 6.5 jaar. Daaruit blijkt dat de test een goede interne consistentie heeft, en dat de hertestbetrouwbaarheid goed is. Uit de gegevens blijkt ook dat de verhouding van sterke linkerhandvoorkeur ten opzichte van sterke rechterhandvoorkeur bij de kinderen ongeveer hetzelfde is als bij eerstejaars Psychologiestudenten. Onder de kinderen vindt men echter 25% die nog niet een sterke handvoorkeur hebben ontwikkeld, terwijl dat bij de volwassenen ongeveer 10% is.
The present study applied the dimensional approach to test whether self-reported symptoms of Atte... more The present study applied the dimensional approach to test whether self-reported symptoms of Attention Deficit/Hyperactivity Disorder (ADHD) in adults are associated with the speed of interhemispheric interaction. A sample of first grade students (N = 112) completed Conners' Adult ADHD Rating Scales and letter matching reaction time tasks. In the tasks, participants had to match a single target letter displayed below the fixation cross, either on left or right visual field, with one of two letters displayed above the fixation cross, one letter on each visual field. For each task, identical letters were presented either within the same visual field (within hemisphere condition) or across visual fields (across hemisphere condition). Interhemispheric interaction was indexed as the difference in mean reaction time between within and across hemisphere conditions. Comorbid problems such as depression, anxiety, and stress may affect task performance and are controlled for in this study...
Children with developmental coordination disorder (DCD) face evident motor difficulties in daily ... more Children with developmental coordination disorder (DCD) face evident motor difficulties in daily functioning. Little is known, however, about their difficulties in specific activities of daily living (ADL). The purposes of this study were: (1) to investigate differences between children with DCD and their peers with typical development for ADL performance, learning, and participation, and (2) to explore the predictive values of these aspects. This was a cross-sectional study. In both a clinical sample of children diagnosed with DCD (n=25 [21 male, 4 female], age range=5-8 years) and a group of peers with typical development (25 matched controls), the children's parents completed the DCDDaily-Q. Differences in scores between the groups were investigated using t tests for performance and participation and Pearson chi-square analysis for learning. Multiple regression analyses were performed to explore the predictive values of performance, learning, and participation. Compared with their peers, children with DCD showed poor performance of ADL and less frequent participation in some ADL. Children with DCD demonstrated heterogeneous patterns of performance (poor in 10%-80% of the items) and learning (delayed in 0%-100% of the items). In the DCD group, delays in learning of ADL were a predictor for poor performance of ADL, and poor performance of ADL was a predictor for less frequent participation in ADL compared with the control group. A limited number of children with DCD were addressed in this study. This study highlights the impact of DCD on children's daily lives and the need for tailored intervention.
Background / Purpose: To develop an instrument for objective and systematic assessment of activit... more Background / Purpose: To develop an instrument for objective and systematic assessment of activities of daily living (ADL) in 5 to 8 year old children: the DCDDailyTo confirm the validity and reliability of the DCDDaily Main conclusion: The DCDDaily is the first instrument for objective and systematic assessment of ADL in children with daily living skills (DCD). The DCDDaily differentiates the performance of ADL between children with DCD and controls.
Background / Purpose: Reported variation in frequency of left-handedness between cultures ranges ... more Background / Purpose: Reported variation in frequency of left-handedness between cultures ranges from 0.5 to 24%. We investigated hand skill and handedness in a nonindustrial population in the highlands of New Guinea where people still live a traditional life reflecting conditions in which handedness may have evolved. Main conclusion: No age effects on lateralizationExpected developmental effects on performance
The aim of this review was to gather information on how well authors comply to DSM criteria in th... more The aim of this review was to gather information on how well authors comply to DSM criteria in their description and selection of children with DCD. We investigated which selection criteria were used in experimental and intervention studies published in the last 5years (2010-2014). Results on 176 papers are summarized. Compliance to the DSM criteria has improved over this time period. In general, detailed information was provided on motor performance using standardized test scores and cut-off values are reported. Method sections were far less detailed about other DSM criteria (i.e., whether motor coordination problems interfered with activities of daily living and how IQ, other medical conditions or co-occurring disorders were checked). Views on how the new DSM-5 criteria could be specified for clinical and research use are discussed.
Research in developmental disabilities, Jan 6, 2014
This article presents a review of the studies that have analysed the motor skills of ADHD childre... more This article presents a review of the studies that have analysed the motor skills of ADHD children without medication and the influence of medication on their motor skills. The following two questions guided the study: What is the evidence of impairment of motor skills and aspects of motor control among children with ADHD aged between 6 and 16 years? What are the effects of ADHD medication on motor skills and motor control? The following keywords were introduced in the main databases: attention disorder and/or ADHD, motor skills and/or handwriting, children, medication. Of the 45 articles retrieved, 30 described motor skills of children with ADHD and 15 articles analysed the influence of ADHD medication on motor skills and motor control. More than half of the children with ADHD have difficulties with gross and fine motor skills. The children with ADHD inattentive subtype seem to present more impairment of fine motor skills, slow reaction time, and online motor control during complex...
Rhythmic interlimb coordination arises from the interaction of intrinsic dynamics and behavioral ... more Rhythmic interlimb coordination arises from the interaction of intrinsic dynamics and behavioral information, that is, intention, memory, or external information specifying the required coordination pattern. This study investigates the influence of the content of memorized behavioral information on coordination in musically experienced and inexperienced participants. These groups are hypothesized to have different intrinsic dynamics for this task. Stability was assessed in a switching task (variability and switching time). The in-phase, anti-phase, and 90 degrees -phase difference were specified in a neutral and an ecologically relevant manner. Musicians showed more stable coordination than nonmusicians did. No interaction effect was found with memorized behavioral information. Behavioral information showed an interaction effect with phase pattern on coordination variability, with the strongest effect for the 90 degrees -phase pattern. Switching time was affected largely in line wit...
The major goal of the current study was to investigate the association between continuous perform... more The major goal of the current study was to investigate the association between continuous performance tests (CPTs) and the heart rate variability (HRV) of attention deficit hyperactivity disorder (ADHD) children. The HRV, specifically the 0.10-Hz component, may be considered to be a psychophysiological index of effort allocation (motivation): The less effort the subject allocates, the greater the 0.10-Hz component. Results indicated that, compared to controls, ADHD subjects had a greater 0.10-Hz component, which was associated with poor test performance over time. Thus, using a psychophysiological measure, we were able to confirm the clinical concept of ADHD from a motivational perspective.
Electroencephalography and clinical neurophysiology, 1984
The functional significance of event-related desynchronization (ERD) of alpha rhythm was investig... more The functional significance of event-related desynchronization (ERD) of alpha rhythm was investigated in a task which manipulated cognitive load and event rate. It was found that with increasing cognitive load the amount and duration of ERD increased. When a slow event rate was used the mean relative desynchronization of alpha rhythm and duration of ERD increased. These effects were found to be independent of one another. These results were interpreted as indicating that the mean ERD of alpha rhythm is sensitive to the selective attention demands of a task and the surprise value of stimuli.
Electroencephalography and Clinical Neurophysiology, 1992
The effects of a subject's activation state on cognitive processing were studied, while subjects ... more The effects of a subject's activation state on cognitive processing were studied, while subjects performed verbal and non-verbal tasks under a speed and accuracy instruction. It was found that stressing speed influenced the level of prestimulus alpha power and consequently the amount of relative event-related desynchronization (ERD). Increasing task complexity led to an increase in the amount and duration of relative ERD. Both prestimulus level of alpha power and relative ERD were asymmetrically distributed over the left and right hemispheres. No verbal/non-verbal task-dependent asymmetries in phasic ERD were found. The data suggest that the level of prestimulus alpha power is mainly influenced by the subject's activation state, whereas relative ERD mainly reflects phasic changes in cognitive processing.
Motorische gevolgen van laesies in de basale ganglia en wat zij ons kunnen leren over het functio... more Motorische gevolgen van laesies in de basale ganglia en wat zij ons kunnen leren over het functioneren van deze hersenstructuur 83
The development of static balance is a basic characteristic of normal motor development. Most dev... more The development of static balance is a basic characteristic of normal motor development. Most developmental motor tests include a measure of static balance. Children with Developmental Coordination Disorder (DCD) often fail this item. This study reviews the balance problems of children with DCD. The general conclusion is drawn that under normal conditions static balance control is not a problem for children with DCD. Only in difficult, unattended, or novel situations such children seem to suffer from increased postural sway. These findings raise the question of what happens when balance is lost. The present study addresses the strength of correlation between the electromyography (EMG) and force plate signals in one-leg stance over epochs of stable and unstable balance. Four groups of children were involved in the study: two age groups and a group of children with DCD and balance problems and their controls. The results show a clear involvement of tibialis anterior and peroneus muscles in the control of lateral balance in all conditions and groups. The group of children with DCD and balance problems, however, showed a weaker coupling between EMG and corrective force compared with control children, indicating non-optimal balance
Preterm infants are exposed to the visual environment earlier than fullterm infants, but whether ... more Preterm infants are exposed to the visual environment earlier than fullterm infants, but whether early exposure affects later development is unclear. Our aim was to investigate whether the development of visual disengagement capacity during the first 6 months postterm was associated with cognitive and motor outcomes at school age, and whether associations differed between fullterms and low-risk preterms. Seventeen fullterms and ten low-risk preterms were tested in a gaze shifting task every 4 weeks until 6 months postterm. The longitudinal data were converted into single continuous variables by fitting the data with an S-shaped curve (frequencies of looks) or an inverse model (latencies of looks). Neuropsychological test results at school age were converted into composite z scores. We then performed linear regression analyses for each functional domain at school age with the variables measuring infant visual attention as separate predictors and adjusting for maternal level of educat...
During early infancy major developmental changes, both in the variety of body movements and in vi... more During early infancy major developmental changes, both in the variety of body movements and in visual attention, help the infant to explore its surroundings. Both behaviours depend on a gradual shift from subcortical to cortical functioning. First, to determine whether preterms reach mature levels of movement variety (the number of different movement patterns) and visual attention earlier than fullterms. Second, to determine whether individual developmental trajectories of movement variety and visual attention were associated. Finally, we compared the associations of developmental trajectories between fullterm and preterm infants. In this longitudinal study, 20 fullterm and 9 low-risk preterm infants performed a visual disengagement task every four weeks from six weeks until six months postterm. For each infant we drew up developmental trajectories for movement variety, and for frequencies and latencies of looks. We analyzed the developmental trajectories by means of general linear ...
In een longitudinale studie is aangetoond dat de groeispurt in de puberteit bij jongens gepaard g... more In een longitudinale studie is aangetoond dat de groeispurt in de puberteit bij jongens gepaard gaat met een vertraging in de ontwikkeling van sensomotorische vaardigheden. De hoeveelheid fysieke activiteit blijkt positief gerelateerd aan de sensomotorische vaardigheden, maar heeft weinig invloed op de negatieve effecten van de sterke toename in groei. Het is opmerkelijk dat jongens met Developmental Coordination Disorder (DCD), die bij het ingaan van de puberteit al een zwakke motoriek hebben, relatief weinig hinder lijken te ondervinden van de groeispurt. Een aantal van deze kinderen vertoont zelfs een snelle ontwikkeling gedurende de puberteit.
This article presents a review of the studies that have analysed the motor skills of ADHD childre... more This article presents a review of the studies that have analysed the motor skills of ADHD children with without medication and the influence of medication on their motor skills. The following two questions guided the study: What is the evidence of impairment of motor skills and aspects of motor control among children with ADHD aged between 6 and 16 years? What are the effects of ADHD medication on motor skills and motor control?
The following keywords were introduced in the main databases: attention disorder and/or ADHD, motor skills and/or handwriting, children, medication. Of the 45 articles retrieved, 30 described motor skills of children with ADHD and 15 articles analysed the influence of ADHD medication on motor skills and motor control.
More than half of the children with ADHD have difficulties with gross and fine motor skills. The children with ADHD inattentive subtype seem to present more impairment of fine motor skills, slow reaction time, and online motor control during complex tasks. The proportion of children with ADHD who improved their motor skills to the normal range by using medication varied from 28% to 67% between studies. The children who still show motor deficit while on medication might meet the diagnostic criteria of developmental coordination disorder (DCD). It is important to assess motor skills among children with ADHD because of the risk of reduced participation in activities of daily living that require motor coordination and attention.
The aim of this paper is to discuss if criteria used for diagnosing children for clinical purpose... more The aim of this paper is to discuss if criteria used for diagnosing children for clinical purposes should be the same as for the selection of children with Developmental Coordination Disorder for research. Next, we give an overview of the criteria mentioned in the development of the European guideline for diagnosing Developmental Coordination Disorder and the implementation of this guideline in different countries. To gain insight into current clinical practice, we also reviewed the medical files of children attending rehabilitation centers for the criteria used to diagnose Developmental Coordination Disorder in the Netherlands. To conclude, we state our expert opinion on why and when research and clinical criteria for Developmental Coordination Disorder should or should not be the same.
Children with developmental coordination disorder (DCD) face evident motor difficulties in daily ... more Children with developmental coordination disorder (DCD) face evident motor difficulties in daily functioning. Little is known, however, about their difficulties in specific activities of daily living (ADL). The purposes of this study were: (1) to investigate differences between children with DCD and their peers with typical development for ADL performance, learning, and participation, and (2) to explore the predictive values of these aspects. This was a cross-sectional study. In both a clinical sample of children diagnosed with DCD (n=25 [21 male, 4 female], age range=5-8 years) and a group of peers with typical development (25 matched controls), the children's parents completed the DCDDaily-Q. Differences in scores between the groups were investigated using t tests for performance and participation and Pearson chi-square analysis for learning. Multiple regression analyses were performed to explore the predictive values of performance, learning, and participation. Compared with ...
Many clinical studies reported a compromised brain lateralization in patients with Attention-Defi... more Many clinical studies reported a compromised brain lateralization in patients with Attention-Deficit/Hyperactivity Disorder (ADHD) without being conclusive about whether the deficit existed in the left or right hemisphere. It is well-recognized that studying ADHD dimensionally is more controlled for comorbid problems and medication effects, and provides more accurate assessment of the symptoms. Therefore, the present study applied the dimensional approach to test the relationship between brain lateralization and self-reported ADHD symptoms in a population sample. Eighty-five right-handed university students filled in the Conners' Adult ADHD Rating Scales and performed a lateralization reaction time task. The task consists of two matching conditions: one condition requires nominal identification for letters tapping left hemisphere specialization (Letter Name-Identity condition) and the other one requires physical and visuospatial identification for shapes tapping right hemisphere...
Deze bijdrage betreft een handvoorkeurstest voor kinderen van 5 tot 7 jaar. Eerst wordt de ontwik... more Deze bijdrage betreft een handvoorkeurstest voor kinderen van 5 tot 7 jaar. Eerst wordt de ontwikkeling van handvoorkeur en het belang van de bepaling ervan kort besproken. Daarna worden aspecten van de betrouwbaarheid en validiteit besproken aan de hand van testgegevens van 67 kinderen van gemiddeld 6.5 jaar. Daaruit blijkt dat de test een goede interne consistentie heeft, en dat de hertestbetrouwbaarheid goed is. Uit de gegevens blijkt ook dat de verhouding van sterke linkerhandvoorkeur ten opzichte van sterke rechterhandvoorkeur bij de kinderen ongeveer hetzelfde is als bij eerstejaars Psychologiestudenten. Onder de kinderen vindt men echter 25% die nog niet een sterke handvoorkeur hebben ontwikkeld, terwijl dat bij de volwassenen ongeveer 10% is.
The present study applied the dimensional approach to test whether self-reported symptoms of Atte... more The present study applied the dimensional approach to test whether self-reported symptoms of Attention Deficit/Hyperactivity Disorder (ADHD) in adults are associated with the speed of interhemispheric interaction. A sample of first grade students (N = 112) completed Conners' Adult ADHD Rating Scales and letter matching reaction time tasks. In the tasks, participants had to match a single target letter displayed below the fixation cross, either on left or right visual field, with one of two letters displayed above the fixation cross, one letter on each visual field. For each task, identical letters were presented either within the same visual field (within hemisphere condition) or across visual fields (across hemisphere condition). Interhemispheric interaction was indexed as the difference in mean reaction time between within and across hemisphere conditions. Comorbid problems such as depression, anxiety, and stress may affect task performance and are controlled for in this study...
Children with developmental coordination disorder (DCD) face evident motor difficulties in daily ... more Children with developmental coordination disorder (DCD) face evident motor difficulties in daily functioning. Little is known, however, about their difficulties in specific activities of daily living (ADL). The purposes of this study were: (1) to investigate differences between children with DCD and their peers with typical development for ADL performance, learning, and participation, and (2) to explore the predictive values of these aspects. This was a cross-sectional study. In both a clinical sample of children diagnosed with DCD (n=25 [21 male, 4 female], age range=5-8 years) and a group of peers with typical development (25 matched controls), the children's parents completed the DCDDaily-Q. Differences in scores between the groups were investigated using t tests for performance and participation and Pearson chi-square analysis for learning. Multiple regression analyses were performed to explore the predictive values of performance, learning, and participation. Compared with their peers, children with DCD showed poor performance of ADL and less frequent participation in some ADL. Children with DCD demonstrated heterogeneous patterns of performance (poor in 10%-80% of the items) and learning (delayed in 0%-100% of the items). In the DCD group, delays in learning of ADL were a predictor for poor performance of ADL, and poor performance of ADL was a predictor for less frequent participation in ADL compared with the control group. A limited number of children with DCD were addressed in this study. This study highlights the impact of DCD on children's daily lives and the need for tailored intervention.
Background / Purpose: To develop an instrument for objective and systematic assessment of activit... more Background / Purpose: To develop an instrument for objective and systematic assessment of activities of daily living (ADL) in 5 to 8 year old children: the DCDDailyTo confirm the validity and reliability of the DCDDaily Main conclusion: The DCDDaily is the first instrument for objective and systematic assessment of ADL in children with daily living skills (DCD). The DCDDaily differentiates the performance of ADL between children with DCD and controls.
Background / Purpose: Reported variation in frequency of left-handedness between cultures ranges ... more Background / Purpose: Reported variation in frequency of left-handedness between cultures ranges from 0.5 to 24%. We investigated hand skill and handedness in a nonindustrial population in the highlands of New Guinea where people still live a traditional life reflecting conditions in which handedness may have evolved. Main conclusion: No age effects on lateralizationExpected developmental effects on performance
The aim of this review was to gather information on how well authors comply to DSM criteria in th... more The aim of this review was to gather information on how well authors comply to DSM criteria in their description and selection of children with DCD. We investigated which selection criteria were used in experimental and intervention studies published in the last 5years (2010-2014). Results on 176 papers are summarized. Compliance to the DSM criteria has improved over this time period. In general, detailed information was provided on motor performance using standardized test scores and cut-off values are reported. Method sections were far less detailed about other DSM criteria (i.e., whether motor coordination problems interfered with activities of daily living and how IQ, other medical conditions or co-occurring disorders were checked). Views on how the new DSM-5 criteria could be specified for clinical and research use are discussed.
Research in developmental disabilities, Jan 6, 2014
This article presents a review of the studies that have analysed the motor skills of ADHD childre... more This article presents a review of the studies that have analysed the motor skills of ADHD children without medication and the influence of medication on their motor skills. The following two questions guided the study: What is the evidence of impairment of motor skills and aspects of motor control among children with ADHD aged between 6 and 16 years? What are the effects of ADHD medication on motor skills and motor control? The following keywords were introduced in the main databases: attention disorder and/or ADHD, motor skills and/or handwriting, children, medication. Of the 45 articles retrieved, 30 described motor skills of children with ADHD and 15 articles analysed the influence of ADHD medication on motor skills and motor control. More than half of the children with ADHD have difficulties with gross and fine motor skills. The children with ADHD inattentive subtype seem to present more impairment of fine motor skills, slow reaction time, and online motor control during complex...
Rhythmic interlimb coordination arises from the interaction of intrinsic dynamics and behavioral ... more Rhythmic interlimb coordination arises from the interaction of intrinsic dynamics and behavioral information, that is, intention, memory, or external information specifying the required coordination pattern. This study investigates the influence of the content of memorized behavioral information on coordination in musically experienced and inexperienced participants. These groups are hypothesized to have different intrinsic dynamics for this task. Stability was assessed in a switching task (variability and switching time). The in-phase, anti-phase, and 90 degrees -phase difference were specified in a neutral and an ecologically relevant manner. Musicians showed more stable coordination than nonmusicians did. No interaction effect was found with memorized behavioral information. Behavioral information showed an interaction effect with phase pattern on coordination variability, with the strongest effect for the 90 degrees -phase pattern. Switching time was affected largely in line wit...
The major goal of the current study was to investigate the association between continuous perform... more The major goal of the current study was to investigate the association between continuous performance tests (CPTs) and the heart rate variability (HRV) of attention deficit hyperactivity disorder (ADHD) children. The HRV, specifically the 0.10-Hz component, may be considered to be a psychophysiological index of effort allocation (motivation): The less effort the subject allocates, the greater the 0.10-Hz component. Results indicated that, compared to controls, ADHD subjects had a greater 0.10-Hz component, which was associated with poor test performance over time. Thus, using a psychophysiological measure, we were able to confirm the clinical concept of ADHD from a motivational perspective.
Electroencephalography and clinical neurophysiology, 1984
The functional significance of event-related desynchronization (ERD) of alpha rhythm was investig... more The functional significance of event-related desynchronization (ERD) of alpha rhythm was investigated in a task which manipulated cognitive load and event rate. It was found that with increasing cognitive load the amount and duration of ERD increased. When a slow event rate was used the mean relative desynchronization of alpha rhythm and duration of ERD increased. These effects were found to be independent of one another. These results were interpreted as indicating that the mean ERD of alpha rhythm is sensitive to the selective attention demands of a task and the surprise value of stimuli.
Electroencephalography and Clinical Neurophysiology, 1992
The effects of a subject's activation state on cognitive processing were studied, while subjects ... more The effects of a subject's activation state on cognitive processing were studied, while subjects performed verbal and non-verbal tasks under a speed and accuracy instruction. It was found that stressing speed influenced the level of prestimulus alpha power and consequently the amount of relative event-related desynchronization (ERD). Increasing task complexity led to an increase in the amount and duration of relative ERD. Both prestimulus level of alpha power and relative ERD were asymmetrically distributed over the left and right hemispheres. No verbal/non-verbal task-dependent asymmetries in phasic ERD were found. The data suggest that the level of prestimulus alpha power is mainly influenced by the subject's activation state, whereas relative ERD mainly reflects phasic changes in cognitive processing.
Motorische gevolgen van laesies in de basale ganglia en wat zij ons kunnen leren over het functio... more Motorische gevolgen van laesies in de basale ganglia en wat zij ons kunnen leren over het functioneren van deze hersenstructuur 83
The development of static balance is a basic characteristic of normal motor development. Most dev... more The development of static balance is a basic characteristic of normal motor development. Most developmental motor tests include a measure of static balance. Children with Developmental Coordination Disorder (DCD) often fail this item. This study reviews the balance problems of children with DCD. The general conclusion is drawn that under normal conditions static balance control is not a problem for children with DCD. Only in difficult, unattended, or novel situations such children seem to suffer from increased postural sway. These findings raise the question of what happens when balance is lost. The present study addresses the strength of correlation between the electromyography (EMG) and force plate signals in one-leg stance over epochs of stable and unstable balance. Four groups of children were involved in the study: two age groups and a group of children with DCD and balance problems and their controls. The results show a clear involvement of tibialis anterior and peroneus muscles in the control of lateral balance in all conditions and groups. The group of children with DCD and balance problems, however, showed a weaker coupling between EMG and corrective force compared with control children, indicating non-optimal balance
Preterm infants are exposed to the visual environment earlier than fullterm infants, but whether ... more Preterm infants are exposed to the visual environment earlier than fullterm infants, but whether early exposure affects later development is unclear. Our aim was to investigate whether the development of visual disengagement capacity during the first 6 months postterm was associated with cognitive and motor outcomes at school age, and whether associations differed between fullterms and low-risk preterms. Seventeen fullterms and ten low-risk preterms were tested in a gaze shifting task every 4 weeks until 6 months postterm. The longitudinal data were converted into single continuous variables by fitting the data with an S-shaped curve (frequencies of looks) or an inverse model (latencies of looks). Neuropsychological test results at school age were converted into composite z scores. We then performed linear regression analyses for each functional domain at school age with the variables measuring infant visual attention as separate predictors and adjusting for maternal level of educat...
During early infancy major developmental changes, both in the variety of body movements and in vi... more During early infancy major developmental changes, both in the variety of body movements and in visual attention, help the infant to explore its surroundings. Both behaviours depend on a gradual shift from subcortical to cortical functioning. First, to determine whether preterms reach mature levels of movement variety (the number of different movement patterns) and visual attention earlier than fullterms. Second, to determine whether individual developmental trajectories of movement variety and visual attention were associated. Finally, we compared the associations of developmental trajectories between fullterm and preterm infants. In this longitudinal study, 20 fullterm and 9 low-risk preterm infants performed a visual disengagement task every four weeks from six weeks until six months postterm. For each infant we drew up developmental trajectories for movement variety, and for frequencies and latencies of looks. We analyzed the developmental trajectories by means of general linear ...
In een longitudinale studie is aangetoond dat de groeispurt in de puberteit bij jongens gepaard g... more In een longitudinale studie is aangetoond dat de groeispurt in de puberteit bij jongens gepaard gaat met een vertraging in de ontwikkeling van sensomotorische vaardigheden. De hoeveelheid fysieke activiteit blijkt positief gerelateerd aan de sensomotorische vaardigheden, maar heeft weinig invloed op de negatieve effecten van de sterke toename in groei. Het is opmerkelijk dat jongens met Developmental Coordination Disorder (DCD), die bij het ingaan van de puberteit al een zwakke motoriek hebben, relatief weinig hinder lijken te ondervinden van de groeispurt. Een aantal van deze kinderen vertoont zelfs een snelle ontwikkeling gedurende de puberteit.
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Papers by Reint Geuze
The following keywords were introduced in the main databases: attention disorder and/or ADHD, motor skills and/or handwriting, children, medication. Of the 45 articles retrieved, 30 described motor skills of children with ADHD and 15 articles analysed the influence of ADHD medication on motor skills and motor control.
More than half of the children with ADHD have difficulties with gross and fine motor skills. The children with ADHD inattentive subtype seem to present more impairment of fine motor skills, slow reaction time, and online motor control during complex tasks. The proportion of children with ADHD who improved their motor skills to the normal range by using medication varied from 28% to 67% between studies. The children who still show motor deficit while on medication might meet the diagnostic criteria of developmental coordination disorder (DCD). It is important to assess motor skills among children with ADHD because of the risk of reduced participation in activities of daily living that require motor coordination and attention.
The following keywords were introduced in the main databases: attention disorder and/or ADHD, motor skills and/or handwriting, children, medication. Of the 45 articles retrieved, 30 described motor skills of children with ADHD and 15 articles analysed the influence of ADHD medication on motor skills and motor control.
More than half of the children with ADHD have difficulties with gross and fine motor skills. The children with ADHD inattentive subtype seem to present more impairment of fine motor skills, slow reaction time, and online motor control during complex tasks. The proportion of children with ADHD who improved their motor skills to the normal range by using medication varied from 28% to 67% between studies. The children who still show motor deficit while on medication might meet the diagnostic criteria of developmental coordination disorder (DCD). It is important to assess motor skills among children with ADHD because of the risk of reduced participation in activities of daily living that require motor coordination and attention.