Hilde Geurts - Academia.edu (original) (raw)
Papers by Hilde Geurts
Development and Psychopathology, 2005
The main aims of this study were to investigate if children with high-functioning autism~HFA! and... more The main aims of this study were to investigate if children with high-functioning autism~HFA! and children with Tourette syndrome~TS! can be differentiated in their executive functioning~EF! profile compared to normal controls~NCs! and compared to each other and to investigate whether children with HFA or children with TS and a comorbid group of children with both disorders are distinct conditions in terms of EF. Four groups of children participated in this study: HFA, TS, comorbid HFA ϩ TS, and a NC group. All children were in the age range of 6 to 13 years. The groups were compared on five major domains of EF: inhibition, visual working memory, planning, cognitive flexibility, and verbal fluency. Children with HFA scored lower than NC children on all the EFs measured. Children with TS and NC children showed the same EF profile. The HFA group scored lower than the TS group for inhibition of a prepotent response and cognitive flexibility. Children with HFA performed poorer than children with comorbid HFA ϩ TS on all functions, with the exception of inhibiting an ongoing response, interference control, and verbal fluency. Children with TS and children with comorbid HFA ϩ TS could not be differentiated from one another in terms of EF. This study indicates that EF deficits are highly characteristic of children with HFA in comparison to children with TS and NC. The results suggest that for the comparison between HFA and TS groups, it is important to take into account comorbidity. A reevaluation of the EF hypothesis in children with TS is suggested.
Neuroscience & Biobehavioral Reviews, 2003
Five models of attention deficit/hyperactivity disorder (ADHD) are reviewed. It is proposed that ... more 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. q
A selective review of research in the executive functioning (EF) is given for attention deficit h... more 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.
Neuroscience and Biobehavioral Reviews, 2011
We propose to bring together the hitherto rather separate research fields of autism spectrum diso... more We propose to bring together the hitherto rather separate research fields of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD), and argue that by contrasting and combining findings of the endophenotypes of ASD and ADHD new insights can be gained into the etiology and pathophysiology of these two disorders. Given the highly heritable nature of both disorders, studies of the
Journal of Attention Disorders, 2014
This study assesses planning skills of adolescents with ADHD using a multi-method assessment and ... more This study assesses planning skills of adolescents with ADHD using a multi-method assessment and explores subtype differences between inattentive and combined subtypes. One hundred fifteen adolescents with ADHD and 34 typically developing controls completed subtests of the Delis-Kaplan Executive Function System (D-KEFS), Behavioral Assessment of the Dysexecutive Syndrome (BADS), and Behavior Rating Inventory of Executive Function (BRIEF). No group differences were found on the D-KEFS. The BADS Zoo Map test showed longer completion times in the inattentive than in the combined subtype and controls. The BRIEF showed more planning problems in adolescents with ADHD (both subtypes) than in controls, with the combined subtype showing most problems on overall executive functioning. Only a proportion of adolescents with ADHD shows planning deficits. To capture these planning problems in adolescents with ADHD, it seems important to use multiple measures of planning, both ratings and "less structured" neurocognitive measures of planning.
Trends in Cognitive Sciences, 2009
Psychiatry Research, 2005
Cortisol has been implicated in psychobiological explanations of antisocial behavior. This study ... more Cortisol has been implicated in psychobiological explanations of antisocial behavior. This study measured basal salivary cortisol in a sample of 25 children (age range 6 to 12 years) selected to vary in levels of antisocial behavior. Regression analyses were used to predict cortisol concentrations from parent-and teacher-reported symptoms. Parent-reported symptoms did not predict basal cortisol. Teacher-reported conduct disorder (CD) symptoms explained 38% of the variance in the cortisol concentrations, with high symptom severity associated with low cortisol. When a distinction was made between aggressive and non-aggressive CD symptoms, aggressive CD symptoms were more clearly related to low cortisol than non-aggressive CD symptoms. In contrast to previous research, no evidence was found for a mediating role of anxiety symptoms in the relationship between CD and cortisol. The results support biologically based models of antisocial behavior in children that involve reduced autonomic activity. D
Journal of Experimental Psychology: Learning, Memory, and Cognition, 1999
Journal of Child Psychology and Psychiatry, 2008
Background: The object of this study was to analyze the executive functioning of children with at... more Background: The object of this study was to analyze the executive functioning of children with attention deficit hyperactivity disorder (ADHD) or reading disability (RD) independent of their non-executive deficits. Methods: Three carefully diagnosed groups of children, aged between 7 and 12 years (35 ADHD, 22 RD and 30 typically developing children), 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. Additional tasks were selected for each domain to control for non-executive processing. Results: ADHD children were impaired on interference control, but not on prepotent and ongoing response suppression. ADHD showed deficits on visual working memory, planning, cognitive flexibility and phonetic fluency. RD children were impaired on phonetic fluency. The only EF measure that differentiated ADHD from RD was planning. Conclusions: The present sample of ADHD children showed several EF deficits, whereas RD children were almost spared executive dysfunction, but exhibited deficits in phonetic fluency.
Journal of Child Psychology and Psychiatry, 2004
Background: The objective of this study is to identify intact and deficient cognitive processes i... more 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.
Journal of Autism and Developmental Disorders, 2014
Numerous studies investigated executive functioning (EF) problems in people with autism spectrum ... more Numerous studies investigated executive functioning (EF) problems in people with autism spectrum disorders (ASD) using laboratory EF tasks. As laboratory task performances often differ from real life observations, the current study focused on EF in everyday life of 118 children and adolescents with ASD (6-18 years). We investigated age-related and individual differences in EF problems as reported by parents on the Behavioral Rating Inventory Executive Functions (BRIEF: Gioia et al. in Behavior rating inventory of executive function. Psychological Assessment Resources, Odesse 2000), and examined the association with autism severity. Inhibition problems were mostly found in the youngest group (6-to 8-year-olds), whereas problems with planning where more evident for 12-to 14-year-olds as compared to 9-to 11-year-olds. In a subsample of participants meeting the ADOS ASD cut-off criteria the age related differences in planning were absent, while problems with cognitive flexibility were less apparent in 15-to 18-year-olds, compared to 9-to 11-, and 12-to 14-year olds. EF problems surpassing the clinical cutoff were only observed in 20 % (planning) to 51 % (cognitive flexibility) of the children and adolescents, and no relation was found with ASD symptom severity. This underlines the heterogeneous nature of ASD.
Journal of Autism and Developmental Disorders, 2009
The current study explored whether inhibitory control deficits in high functioning autism (HFA) e... more The current study explored whether inhibitory control deficits in high functioning autism (HFA) emerged when socially relevant stimuli were used and whether arousal level affected the performance. A Go/NoGo paradigm, with socially relevant stimuli and varying presentation rates, was applied in 18 children with HFA (including children with autism or Asperger syndrome) and 22 typically developing children (aged 8-13 years). Children with HFA did not show inhibitory control deficits compared to the control group, but their performance deteriorated in the slow presentation rate condition. Findings were unrelated to children's abilities to recognize emotions. Hence, rather than a core deficit in inhibitory control, low arousal level in response to social stimuli might influence the responses given by children with HFA.
Journal of Abnormal Child Psychology, 2006
This study investigated hot and cool aspects of cognitive control in children with Attention Defi... more This study investigated hot and cool aspects of cognitive control in children with Attention Deficit Hyperactivity Disorder (ADHD). The study aimed to: 1) replicate the postulated response inhibition deficit of children with ADHD; 2) explore whether children with ADHD choose disadvantageously in a decision-making task and to explore the mechanisms underlying the expected response pattern; and 3) study whether performance on a combination of hot and cool executive control measures has predictive value for a ADHD diagnosis. The sample consisted of 20 children with ADHD and 22 normal developing children (NC, 8 to 12 years) matched on age, FSIQ, and gender. Two paradigms have been applied: 1) the stop signal paradigm, and 2) the adapted children's version of the IOWA Gambling task. There were no group differences for both paradigms. Both groups chose in a reward-oriented manner and seemed to develop the ability to take future consequences into account in making decisions. Moreover, feedback resulted in direct behavioral changes.
European Journal of Developmental Psychology, 2010
To cite this Article Geurts, Hilde M., Broeders, Mark and Nieuwland, Mante S.(2010) 'Thinking out... more To cite this Article Geurts, Hilde M., Broeders, Mark and Nieuwland, Mante S.(2010) 'Thinking outside the executive functions box: Theory of mind and pragmatic abilities in attention deficit/hyperactivity disorder', European Journal of Developmental Psychology, 7: 1, 135 -151,
European Child & Adolescent Psychiatry, 2010
Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are both highl... more Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are both highly heritable neurodevelopmental disorders. Evidence indicates both disorders co-occur with a high frequency, in 20-50% of children with ADHD meeting criteria for ASD and in 30-80% of ASD children meeting criteria for ADHD. This review will provide an overview on all available studies [family based, twin, candidate gene, linkage, and genome wide association (GWA) studies] shedding light on the role of shared genetic underpinnings of ADHD and ASD. It is concluded that family and twin studies do provide support for the hypothesis that ADHD and ASD originate from partly similar familial/genetic factors. Only a few candidate gene studies, linkage studies and GWA studies have specifically addressed this co-occurrence, pinpointing to some promising pleiotropic genes, loci and single nucleotide polymorphisms (SNPs), but the research field is in urgent need for better designed and powered studies to tackle this complex issue. We propose that future studies examining shared familial etiological factors for ADHD and ASD use a family-based design in which the same phenotypic (ADHD and ASD), candidate endophenotypic, and environmental measurements are obtained from all family members. Multivariate multi-level models are probably best suited for the statistical analysis.
Child Neuropsychology, 2012
Inhibition deficits, including deficits in prepotent response inhibition and interference control... more Inhibition deficits, including deficits in prepotent response inhibition and interference control, are core deficits in ADHD. The predictive value of prepotent response inhibition and interference control was assessed for outcome in a 10-week treatment trial with methylphenidate. Thirty-four children with ADHD (ages 8-12) received 10 weeks of methylphenidate treatment. At pretest prepotent response inhibition was assessed using the Stop-Signal Task; interference control was assessed using the Stroop Color-Word task. Methylphenidate was individually titrated to an optimal dose. Treatment outcome was assessed by parent- and teacher-rated ADHD behavior. Only stop-signal reaction time of the Stop-Signal Task was a significant predictor of parent-rated levels of inattention and hyperactivity/impulsivity at outcome. Children with lower levels of inhibition showed worse outcome after 10 weeks of treatment, independent of medication dose. Low levels of prepotent response inhibition are associated with worse response to treatment with methylphenidate. Prepotent response inhibition may be an intermediate phenotypical predictor of treatment outcome.
Behavioural Brain Research, 2002
A selective review of research in the executive functioning (EF) is given for attention deficit h... more 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.
Autism, 2014
Repetitive behavior is a key characteristic of autism spectrum disorders. Our aim was to investig... more Repetitive behavior is a key characteristic of autism spectrum disorders. Our aim was to investigate the hypothesis that this abnormal behavioral repetition results from a tendency to over-rely on habits at the expense of flexible, goal-directed action. Twenty-four children with autism spectrum disorders and 24 age- and gender-matched controls (8-12 years) initially learned to give specific responses to different pictorial stimuli in order to gain valuable outcomes. Subsequently, in the "slips-of-action" test, some of these outcomes were no longer valuable. Children needed to refrain from responding when stimuli were shown that signaled the availability of those outcomes while continuing to respond for the still-valuable outcomes. Reliance on habits should lead to "slips of action" toward no longer valuable outcomes. Therefore, the children's ability to respond selectively for still-valuable outcomes provides a measure of relative habitual versus goal-directed control. Two additional tasks were included to control for general task characteristics (i.e. working memory and inhibition). Children with autism spectrum disorders learned equally well as controls and were not impaired at flexibly adjusting their behavior to devaluation of the outcomes or stimuli. We found no evidence for a disruption in the balance between goal-directed and habitual behavioral control in children with autism spectrum disorders.
Autism, 2014
The aim of this study was to analyse the development of verbal working memory in children with hi... more The aim of this study was to analyse the development of verbal working memory in children with high-functioning autism compared to children with attention-deficit/hyperactivity disorder and typically developing children. A total of 34 children with high-functioning autism, 72 children with attention-deficit/hyperactivity disorder and 45 typically developing children (age 9-16 years) were included at baseline and followed up approximately 25 months later. The children were given a letter/number sequencing task to assess verbal working memory. The performance of children with high-functioning autism on verbal working memory did not improve after 2 years, while improvement was observed in children with attention-deficit/hyperactivity disorder and typically developing children. The results indicate a different developmental trajectory for verbal working memory in children with high-functioning autism compared to children with attentiondeficit/hyperactivity disorder and typically developing children. More research is needed to construct a developmental framework more suitable for children with autism spectrum disorder.
Development and Psychopathology, 2005
The main aims of this study were to investigate if children with high-functioning autism~HFA! and... more The main aims of this study were to investigate if children with high-functioning autism~HFA! and children with Tourette syndrome~TS! can be differentiated in their executive functioning~EF! profile compared to normal controls~NCs! and compared to each other and to investigate whether children with HFA or children with TS and a comorbid group of children with both disorders are distinct conditions in terms of EF. Four groups of children participated in this study: HFA, TS, comorbid HFA ϩ TS, and a NC group. All children were in the age range of 6 to 13 years. The groups were compared on five major domains of EF: inhibition, visual working memory, planning, cognitive flexibility, and verbal fluency. Children with HFA scored lower than NC children on all the EFs measured. Children with TS and NC children showed the same EF profile. The HFA group scored lower than the TS group for inhibition of a prepotent response and cognitive flexibility. Children with HFA performed poorer than children with comorbid HFA ϩ TS on all functions, with the exception of inhibiting an ongoing response, interference control, and verbal fluency. Children with TS and children with comorbid HFA ϩ TS could not be differentiated from one another in terms of EF. This study indicates that EF deficits are highly characteristic of children with HFA in comparison to children with TS and NC. The results suggest that for the comparison between HFA and TS groups, it is important to take into account comorbidity. A reevaluation of the EF hypothesis in children with TS is suggested.
Neuroscience & Biobehavioral Reviews, 2003
Five models of attention deficit/hyperactivity disorder (ADHD) are reviewed. It is proposed that ... more 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. q
A selective review of research in the executive functioning (EF) is given for attention deficit h... more 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.
Neuroscience and Biobehavioral Reviews, 2011
We propose to bring together the hitherto rather separate research fields of autism spectrum diso... more We propose to bring together the hitherto rather separate research fields of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD), and argue that by contrasting and combining findings of the endophenotypes of ASD and ADHD new insights can be gained into the etiology and pathophysiology of these two disorders. Given the highly heritable nature of both disorders, studies of the
Journal of Attention Disorders, 2014
This study assesses planning skills of adolescents with ADHD using a multi-method assessment and ... more This study assesses planning skills of adolescents with ADHD using a multi-method assessment and explores subtype differences between inattentive and combined subtypes. One hundred fifteen adolescents with ADHD and 34 typically developing controls completed subtests of the Delis-Kaplan Executive Function System (D-KEFS), Behavioral Assessment of the Dysexecutive Syndrome (BADS), and Behavior Rating Inventory of Executive Function (BRIEF). No group differences were found on the D-KEFS. The BADS Zoo Map test showed longer completion times in the inattentive than in the combined subtype and controls. The BRIEF showed more planning problems in adolescents with ADHD (both subtypes) than in controls, with the combined subtype showing most problems on overall executive functioning. Only a proportion of adolescents with ADHD shows planning deficits. To capture these planning problems in adolescents with ADHD, it seems important to use multiple measures of planning, both ratings and "less structured" neurocognitive measures of planning.
Trends in Cognitive Sciences, 2009
Psychiatry Research, 2005
Cortisol has been implicated in psychobiological explanations of antisocial behavior. This study ... more Cortisol has been implicated in psychobiological explanations of antisocial behavior. This study measured basal salivary cortisol in a sample of 25 children (age range 6 to 12 years) selected to vary in levels of antisocial behavior. Regression analyses were used to predict cortisol concentrations from parent-and teacher-reported symptoms. Parent-reported symptoms did not predict basal cortisol. Teacher-reported conduct disorder (CD) symptoms explained 38% of the variance in the cortisol concentrations, with high symptom severity associated with low cortisol. When a distinction was made between aggressive and non-aggressive CD symptoms, aggressive CD symptoms were more clearly related to low cortisol than non-aggressive CD symptoms. In contrast to previous research, no evidence was found for a mediating role of anxiety symptoms in the relationship between CD and cortisol. The results support biologically based models of antisocial behavior in children that involve reduced autonomic activity. D
Journal of Experimental Psychology: Learning, Memory, and Cognition, 1999
Journal of Child Psychology and Psychiatry, 2008
Background: The object of this study was to analyze the executive functioning of children with at... more Background: The object of this study was to analyze the executive functioning of children with attention deficit hyperactivity disorder (ADHD) or reading disability (RD) independent of their non-executive deficits. Methods: Three carefully diagnosed groups of children, aged between 7 and 12 years (35 ADHD, 22 RD and 30 typically developing children), 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. Additional tasks were selected for each domain to control for non-executive processing. Results: ADHD children were impaired on interference control, but not on prepotent and ongoing response suppression. ADHD showed deficits on visual working memory, planning, cognitive flexibility and phonetic fluency. RD children were impaired on phonetic fluency. The only EF measure that differentiated ADHD from RD was planning. Conclusions: The present sample of ADHD children showed several EF deficits, whereas RD children were almost spared executive dysfunction, but exhibited deficits in phonetic fluency.
Journal of Child Psychology and Psychiatry, 2004
Background: The objective of this study is to identify intact and deficient cognitive processes i... more 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.
Journal of Autism and Developmental Disorders, 2014
Numerous studies investigated executive functioning (EF) problems in people with autism spectrum ... more Numerous studies investigated executive functioning (EF) problems in people with autism spectrum disorders (ASD) using laboratory EF tasks. As laboratory task performances often differ from real life observations, the current study focused on EF in everyday life of 118 children and adolescents with ASD (6-18 years). We investigated age-related and individual differences in EF problems as reported by parents on the Behavioral Rating Inventory Executive Functions (BRIEF: Gioia et al. in Behavior rating inventory of executive function. Psychological Assessment Resources, Odesse 2000), and examined the association with autism severity. Inhibition problems were mostly found in the youngest group (6-to 8-year-olds), whereas problems with planning where more evident for 12-to 14-year-olds as compared to 9-to 11-year-olds. In a subsample of participants meeting the ADOS ASD cut-off criteria the age related differences in planning were absent, while problems with cognitive flexibility were less apparent in 15-to 18-year-olds, compared to 9-to 11-, and 12-to 14-year olds. EF problems surpassing the clinical cutoff were only observed in 20 % (planning) to 51 % (cognitive flexibility) of the children and adolescents, and no relation was found with ASD symptom severity. This underlines the heterogeneous nature of ASD.
Journal of Autism and Developmental Disorders, 2009
The current study explored whether inhibitory control deficits in high functioning autism (HFA) e... more The current study explored whether inhibitory control deficits in high functioning autism (HFA) emerged when socially relevant stimuli were used and whether arousal level affected the performance. A Go/NoGo paradigm, with socially relevant stimuli and varying presentation rates, was applied in 18 children with HFA (including children with autism or Asperger syndrome) and 22 typically developing children (aged 8-13 years). Children with HFA did not show inhibitory control deficits compared to the control group, but their performance deteriorated in the slow presentation rate condition. Findings were unrelated to children's abilities to recognize emotions. Hence, rather than a core deficit in inhibitory control, low arousal level in response to social stimuli might influence the responses given by children with HFA.
Journal of Abnormal Child Psychology, 2006
This study investigated hot and cool aspects of cognitive control in children with Attention Defi... more This study investigated hot and cool aspects of cognitive control in children with Attention Deficit Hyperactivity Disorder (ADHD). The study aimed to: 1) replicate the postulated response inhibition deficit of children with ADHD; 2) explore whether children with ADHD choose disadvantageously in a decision-making task and to explore the mechanisms underlying the expected response pattern; and 3) study whether performance on a combination of hot and cool executive control measures has predictive value for a ADHD diagnosis. The sample consisted of 20 children with ADHD and 22 normal developing children (NC, 8 to 12 years) matched on age, FSIQ, and gender. Two paradigms have been applied: 1) the stop signal paradigm, and 2) the adapted children's version of the IOWA Gambling task. There were no group differences for both paradigms. Both groups chose in a reward-oriented manner and seemed to develop the ability to take future consequences into account in making decisions. Moreover, feedback resulted in direct behavioral changes.
European Journal of Developmental Psychology, 2010
To cite this Article Geurts, Hilde M., Broeders, Mark and Nieuwland, Mante S.(2010) 'Thinking out... more To cite this Article Geurts, Hilde M., Broeders, Mark and Nieuwland, Mante S.(2010) 'Thinking outside the executive functions box: Theory of mind and pragmatic abilities in attention deficit/hyperactivity disorder', European Journal of Developmental Psychology, 7: 1, 135 -151,
European Child & Adolescent Psychiatry, 2010
Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are both highl... more Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) are both highly heritable neurodevelopmental disorders. Evidence indicates both disorders co-occur with a high frequency, in 20-50% of children with ADHD meeting criteria for ASD and in 30-80% of ASD children meeting criteria for ADHD. This review will provide an overview on all available studies [family based, twin, candidate gene, linkage, and genome wide association (GWA) studies] shedding light on the role of shared genetic underpinnings of ADHD and ASD. It is concluded that family and twin studies do provide support for the hypothesis that ADHD and ASD originate from partly similar familial/genetic factors. Only a few candidate gene studies, linkage studies and GWA studies have specifically addressed this co-occurrence, pinpointing to some promising pleiotropic genes, loci and single nucleotide polymorphisms (SNPs), but the research field is in urgent need for better designed and powered studies to tackle this complex issue. We propose that future studies examining shared familial etiological factors for ADHD and ASD use a family-based design in which the same phenotypic (ADHD and ASD), candidate endophenotypic, and environmental measurements are obtained from all family members. Multivariate multi-level models are probably best suited for the statistical analysis.
Child Neuropsychology, 2012
Inhibition deficits, including deficits in prepotent response inhibition and interference control... more Inhibition deficits, including deficits in prepotent response inhibition and interference control, are core deficits in ADHD. The predictive value of prepotent response inhibition and interference control was assessed for outcome in a 10-week treatment trial with methylphenidate. Thirty-four children with ADHD (ages 8-12) received 10 weeks of methylphenidate treatment. At pretest prepotent response inhibition was assessed using the Stop-Signal Task; interference control was assessed using the Stroop Color-Word task. Methylphenidate was individually titrated to an optimal dose. Treatment outcome was assessed by parent- and teacher-rated ADHD behavior. Only stop-signal reaction time of the Stop-Signal Task was a significant predictor of parent-rated levels of inattention and hyperactivity/impulsivity at outcome. Children with lower levels of inhibition showed worse outcome after 10 weeks of treatment, independent of medication dose. Low levels of prepotent response inhibition are associated with worse response to treatment with methylphenidate. Prepotent response inhibition may be an intermediate phenotypical predictor of treatment outcome.
Behavioural Brain Research, 2002
A selective review of research in the executive functioning (EF) is given for attention deficit h... more 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.
Autism, 2014
Repetitive behavior is a key characteristic of autism spectrum disorders. Our aim was to investig... more Repetitive behavior is a key characteristic of autism spectrum disorders. Our aim was to investigate the hypothesis that this abnormal behavioral repetition results from a tendency to over-rely on habits at the expense of flexible, goal-directed action. Twenty-four children with autism spectrum disorders and 24 age- and gender-matched controls (8-12 years) initially learned to give specific responses to different pictorial stimuli in order to gain valuable outcomes. Subsequently, in the "slips-of-action" test, some of these outcomes were no longer valuable. Children needed to refrain from responding when stimuli were shown that signaled the availability of those outcomes while continuing to respond for the still-valuable outcomes. Reliance on habits should lead to "slips of action" toward no longer valuable outcomes. Therefore, the children's ability to respond selectively for still-valuable outcomes provides a measure of relative habitual versus goal-directed control. Two additional tasks were included to control for general task characteristics (i.e. working memory and inhibition). Children with autism spectrum disorders learned equally well as controls and were not impaired at flexibly adjusting their behavior to devaluation of the outcomes or stimuli. We found no evidence for a disruption in the balance between goal-directed and habitual behavioral control in children with autism spectrum disorders.
Autism, 2014
The aim of this study was to analyse the development of verbal working memory in children with hi... more The aim of this study was to analyse the development of verbal working memory in children with high-functioning autism compared to children with attention-deficit/hyperactivity disorder and typically developing children. A total of 34 children with high-functioning autism, 72 children with attention-deficit/hyperactivity disorder and 45 typically developing children (age 9-16 years) were included at baseline and followed up approximately 25 months later. The children were given a letter/number sequencing task to assess verbal working memory. The performance of children with high-functioning autism on verbal working memory did not improve after 2 years, while improvement was observed in children with attention-deficit/hyperactivity disorder and typically developing children. The results indicate a different developmental trajectory for verbal working memory in children with high-functioning autism compared to children with attentiondeficit/hyperactivity disorder and typically developing children. More research is needed to construct a developmental framework more suitable for children with autism spectrum disorder.