Showing papers in "Developmental Neuropsychology in 2005"
TL;DR: Age trends in performance and task difficulty scales at 2, 3, 4, and 5 to 6 years of age informs theories of executive function development and offers researchers an evidence-based guide to task selection and design.
Abstract: Changes in executive functioning in the preschool years are recognized as playing a critical role in cognitive and social development, yet comprehensive data and recommendations about measurement of these changes are lacking. The performance of 602 preschool children on several executive function tasks was analyzed and reported as (a) age trends in performance and (b) task difficulty scales at 2, 3, 4, and 5 to 6 years of age. This analysis informs theories of executive function development and offers researchers an evidence-based guide to task selection and design.
1,461 citations
TL;DR: This study demonstrates that individuals with autism have impaired face discrimination and recognition and use atypical strategies for processing faces characterized by reduced attention to the eyes and piecemeal rather than configural strategies.
Abstract: This article reviews behavioral and electrophysiological studies of face processing and discusses hypotheses for understanding the nature of face processing impairments in autism. Based on results of behavioral studies, this study demonstrates that individuals with autism have impaired face discrimination and recognition and use atypical strategies for processing faces characterized by reduced attention to the eyes and piecemeal rather than configural strategies. Based on results of electrophysiological studies, this article concludes that face processing impairments are present early in autism, by 3 years of age. Such studies have detected abnormalities in both early (N170 reflecting structural encoding) and late (NC reflecting recognition memory) stages of face processing. Event-related potential studies of young children and adults with autism have found slower speed of processing of faces, a failure to show the expected speed advantage of processing faces versus nonface stimuli, and atypical scalp top...
877 citations
TL;DR: This article focuses on the monitoring and control functions of attention and discusses its contributions to self-regulation from cognitive, temperamental, and biological perspectives.
Abstract: Over the past decade, developmental studies have established connections between executive attention, as studied in neurocognitive models, and effortful control, a temperament system supporting the emergence of self-regulation. Functions associated with the executive attention network overlap with the more general domain of executive function in childhood, which also includes working memory, planning, switching, and inhibitory control (Welch, 2001). Cognitive tasks used with adults to study executive attention can be adapted to children and used with questionnaires to trace the role of attention and effortful control in the development of self-regulation. In this article we focus on the monitoring and control functions of attention and discuss its contributions to self-regulation from cognitive, temperamental, and biological perspectives.
748 citations
TL;DR: Findings confirmed that performance on both types of task develops during the preschool period, but the measures of hot and cool EF showed different patterns of relations with each other and with measures of general intellectual function and temperament.
Abstract: Although executive function (EF) is often considered a domain-general cognitive function, a distinction has been made between the "cool" cognitive aspects of EF more associated with dorsolateral regions of prefrontal cortex and the "hot" affective aspects more associated with ventral and medial regions (Zelazo & M�ller, 2002). Assessments of EF in children have focused almost exclusively on cool EF. In this study, EF was assessed in 3- to 5-year-old children using 2 putative measures of cool EF (Self-Ordered Pointing and Dimensional Change Card Sort) and 2 putative measures of hot EF (Children's Gambling Task and Delay of Gratification). Findings confirmed that performance on both types of task develops during the preschool period. However, the measures of hot and cool EF showed different patterns of relations with each other and with measures of general intellectual function and temperament. These differences provide preliminary evidence that hot and cool EF are indeed distinct, and they encourage furthe...
633 citations
TL;DR: The group with comorbid RD and ADHD exhibited the combination of the deficits in the RD-only and ADHD-only groups, providing evidence against the phenocopy and cognitive subtype hypotheses as explanations for the co-occurrence ofRD and ADHD.
Abstract: Measures of component reading and language skills, executive functions, and processing speed were administered to groups of children with attention deficit hyperactivity disorder (ADHD; n = 113), reading disability (RD; n = 109), both RD and ADHD (n = 64), and neither RD nor ADHD (n = 151). Groups with RD exhibited pronounced deficits on all measures of component reading and language skills, as well as significant weaknesses on measures of verbal working memory, processing speed, and response inhibition. Groups with ADHD exhibited weaknesses on all response-inhibition and processing speed tasks and were impaired on some measures of component reading skills and verbal working memory. The group with comorbid RD and ADHD exhibited the combination of the deficits in the RD-only and ADHD-only groups, providing evidence against the phenocopy and cognitive subtype hypotheses as explanations for the co-occurrence of RD and ADHD. Slow and variable processing speed was characteristic of all 3 clinical groups, suggesting that measures of this domain may be useful for future studies that search for the common genes that increase susceptibility to RD and ADHD.
579 citations
TL;DR: New batteries of EF and ToM tasks that were administered to 140 two-year-olds from predominantly disadvantaged families showed a strong association between EF and toM, which remained significant when effects of verbal ability were controlled.
Abstract: Although numerous studies of preschoolers report robust associations between performance on tests of executive function (EF) and theory of mind (ToM), a lack of developmentally appropriate tasks so far has limited research on these cognitive skills in younger children. Here, we present new batteries of EF and ToM tasks that were administered to 140 two-year-olds from predominantly disadvantaged families, with analyses based on 129 children. Our results showed a strong association between EF and ToM, which remained significant when effects of verbal ability were controlled. Individual differences in EF and ToM were also examined in relation to both distal family factors (social disadvantage, number of siblings) and proximal family factors (quality of child's relationships with parents and siblings). Social disadvantage predicted significant variance in both EF and ToM but did not contribute to the association between these domains. Associations between positive parent-child relationships and both EF and ToM were nonsignificant when verbal ability was controlled. In contrast, positive sibling relationships predicted significant variance in ToM, even controlling for age, verbal ability, EF, social disadvantage, and parent-child relationships.
367 citations
TL;DR: The results suggest that the differences in test scores between the public and private school children depended on some conditions existing outside the school, such as the parents' level of education.
Abstract: Information about the influence of educational variables on the development of executive functions is limited. The aim of this study was to analyze the relation of the parents' educational level and the type of school the child attended (private or public school) to children's executive functioning test performance. Six hundred twenty-two participants, ages 5 to 14 years (276 boys, 346 girls) were selected from Colombia and Mexico and grouped according to three variables: age (5-6, 7-8, 9-10, 11-12, and 13-14 years), gender (boys and girls), and school type (private and public). Eight executive functioning tests taken from the Evaluacion Neuropsicologica Infantil; Matute, Rosselli, Ardila, & Ostrosky, in press) were individually administered: Semantic Verbal Fluency, Phonemic Verbal Fluency, Semantic Graphic Fluency, Nonsemantic Graphic Fluency, Matrices, Similarities, Card Sorting, and the Mexican Pyramid. There was a significant effect of age on all the test scores and a significant effect of type of sc...
355 citations
TL;DR: Books on the characteristics and possible interpretations of the event-related potential (ERP) peaks commonly identified in research are reviewed to serve as a tutorial for general readers interested in neuropsychological research and as a reference source for researchers using ERP techniques.
Abstract: This article reviews literature on the characteristics and possible interpretations of the event-related potential (ERP) peaks commonly identified in research. The description of each peak includes typical latencies, cortical distributions, and possible brain sources of observed activity as well as the evoking paradigms and underlying psychological processes. The review is intended to serve as a tutorial for general readers interested in neuropsychological research and as a reference source for researchers using ERP techniques.
336 citations
TL;DR: The objective was to establish a baseline level of confidence that was high enough to be considered a reliable proxy for executive function in early childhood.
Abstract: (2005). The Measurement of Executive Function in Early Childhood. Developmental Neuropsychology: Vol. 28, No. 2, pp. 561-571.
305 citations
TL;DR: Results support an inhibitory control interpretation of preschoolers' problems on the DCCS task and suggest that young children can have difficulty integrating features not part of a single object and separating features of asingle object so that the object can be categorized first by one attribute and then by another.
Abstract: Fifty-seven children (53% female) at 3 ages (2 1/2, 3, and 3 1/2 years) were tested on the standard Dimensional Change Card Sort (DCCS) task with integrated stimuli (e.g., a red truck) and on a separated-dimensions version where colorless shapes were presented on a colored background (e.g., a black truck on a red background). Roughly twice as many children successfully switched sorting dimensions when color was a property of the background than when color was a property of the shape itself. Children succeeded 6 months earlier in switching sorting criteria when the dimensions were separated. When evidence of both indecision and accuracy was taken into account, a clear and rich developmental progression emerged. These results support an inhibitory control interpretation of preschoolers' problems on the DCCS task. Diamond theorized that young children can have difficulty integrating features not part of a single object and separating features of a single object so that the object can be categorized first by one attribute and then by another. Preschoolers remain stuck in thinking about objects according to the objects' initially relevant attribute (attentional inertia; Kirkham, Cruess, & Diamond, 2003). To switch perspectives, the old way of thinking about the objects must be inhibited. Separating color and shape reduced the need for such inhibition; a truck was always a truck, and the background was always red.
259 citations
TL;DR: It is concluded that formerly hyperactive children manifest greater EF deficits at follow-up in the areas of inattention, disinhibition, and slowed reaction time and greater ADHD behavior during testing, but these problems are mostly confined to those with current ADHD.
Abstract: Tests of several executive functions (EFs) as well as direct observations of symptoms of attention deficit hyperactivity disorder (ADHD) during testing were collected at the young adult follow-up (M = 20 years) on a large sample of hyperactive (H; N = 147) and community control (CC; N = 71) children. The EF tasks included tests of attention, inhibition, and response perseveration. The H group was subdivided into those with and without ADHD (+ or w/o) at follow-up. The H+ADHD group made significantly more inhibition errors than the CC group on a Continuous Performance Test (CPT) and showed more ADHD symptoms while performing the CPT. The H+ADHD group also displayed more ADHD symptoms during a letter cancellation task than did both the hyperactive w/o ADHD and CC groups. Both H groups showed slower reaction times during a Card Playing Task. That subset of hyperactive probands with Conduct Disorder (CD) displayed significantly more perseverative responding on that task than did those without CD, but otherwis...
TL;DR: Complex verbal tasks that required cognitive switching and initiation of efficient lexical retrieval strategies produced the most consistent deficits, whereas cognitive inhibition was intact in high-functioning adults with autistic disorder or Asperger's disorder.
Abstract: The Color-Word Interference Test, Trail Making Test, Verbal Fluency Test, and Design Fluency Test from the Delis-Kaplan Executive Function System (Delis, Kaplan, & Kramer, 2001) were administered to 12 high-functioning adults and adolescents with autistic disorder or Asperger's disorder. Each test included a switching condition in addition to baseline and/or other executive-function conditions. Participants performed significantly below average on a composite measure of executive functioning adjusted for baseline cognitive ability. Complex verbal tasks that required cognitive switching and initiation of efficient lexical retrieval strategies produced the most consistent deficits, whereas cognitive inhibition was intact. We discuss implications of these findings for understanding the neurocognitive substrates of autistic spectrum disorders.
TL;DR: Children with autism were less developed than the comparison group in their language skills, but correlational analyses revealed no specific association between language ability and executive performance in the autism group, while executive performance was positively correlated with language ability in the comparison groups.
Abstract: This study examined executive dysfunction and its relation to language ability in verbal school-age children with autism. Participants were 37 children with autism and 31 nonautistic comparison participants who were matched on age and on verbal and nonverbal IQ but not on language ability, which was lower in the autism group. Children with autism exhibited deficits compared to the comparison group across all 3 domains of executive function that were assessed including working memory (Block Span Backward; Isaacs & Vargha-Khadem, 1989), working memory and inhibitory control (NEPSY Knock-Tap; Korkman, Kirk, & Kemp, 1998), and planning (NEPSY Tower; Korkman et al., 1998). Children with autism were less developed than the comparison group in their language skills, but correlational analyses revealed no specific association between language ability and executive performance in the autism group. In contrast, executive performance was positively correlated with language ability in the comparison group. This pattern of findings suggest that executive dysfunction in autism is not directly related to language impairment per se but rather involves an executive failure to use of language for self-regulation.
University of Michigan1, University of Washington2, Yeshiva University3, University of Colorado Denver4, University of Rochester5, University of Utah6, University of Pittsburgh7, University of California, Davis8, University of California, Los Angeles9, University of California, Irvine10, Boston University11, Yale University12
TL;DR: A significant minority of children with autism without word loss showed a very similar pattern of loss of social-communication skills, a pattern not observed in the children with developmental delays or typical development.
Abstract: In a multisite study of 351 children with autism spectrum disorders, 21 children with developmental delays, and 31 children with typical development, this study used caregiver interviews (i.e., the Autism Diagnostic Interview-Revised) at the time of entry into other research projects and follow-up telephone interviews designed for this project to describe the children's early acquisition and loss of social-communication milestones. Children who had used words spontaneously and meaningfully and then stopped talking were described by their caregivers as showing more gestures, greater participation in social games, and better receptive language before the loss and fewer of these skills after the loss than other children with autism spectrum disorders. A significant minority of children with autism without word loss showed a very similar pattern of loss of social-communication skills, a pattern not observed in the children with developmental delays or typical development.
TL;DR: It is suggested that executive dysfunctions are correlates of ADHD regardless of gender and age, at least through the late teen years, and these impairments are found at ages 9 to 12 and ages 13 to 17.
Abstract: ADHD is known to have neuropsychological correlates, characterized mainly by executive function (EF) deficits. However, most available data are based on studies of boys through age 12. Our goal was to assess whether girls with ADHD express neuropsychological features similar to those found in boys, and whether these impairments are found in both preteen and teen samples. Participants were 101 girls and 103 boys with DSM-III-R ADHD, and 109 comparison girls and 70 boys without ADHD, ages 9 to 17 years. Information on neuropsychological performance was obtained in a standardized manner blind to clinical status. Primary regression analyses controlled for age, socioeconomic status, learning disability, and psychiatric comorbidity. Girls and boys with ADHD were significantly more impaired on some measures of EFs than healthy comparisons but did not differ significantly from each other. With the exception of 1 test score there were no significant Sex x Diagnosis interactions. Moreover, there were no more significant interactions among age, gender, and diagnosis than would be expected by chance. Neuropsychological measures of EFs were comparably impaired in girls compared to boys with ADHD, and these impairments are found at ages 9 to 12 and ages 13 to 17. These findings suggest that executive dysfunctions are correlates of ADHD regardless of gender and age, at least through the late teen years.
TL;DR: Vocal reaction times in naming 3- to 8-letter words were measured in proficient and dyslexic readers and individual analysis indicated 2 profiles of RTs (Types A and B).
Abstract: Vocal reaction times (RTs) in naming 3- to 8-letter words were measured in proficient and dyslexic readers (Study 1). In proficient readers, RTs were independent of word length up to 5-letter words, indicating parallel processing. In the 5- to 8-letter range, RTs increased linearly, indicating sequential processing. Reading experience was associated with both faster discrimination of individual elements and parallel processing of increasingly large word parts. In dyslexics, RTs increased linearly with increasing length indicating reliance on sequential decoding. Individual analysis indicated 2 profiles of RTs (Types A and B). In Study 2, the distinction between A and B dyslexics was not associated with the use of different reading procedures. However, a more marked speed deficit characterized Type B dyslexics.
TL;DR: Better cognitive performance was associated with a less gender-typical finger-length ratio, for both men and women in this group of college students, and a possible curvilinear relation between hormones and cognition in normal populations is discussed.
Abstract: One hundred thirty-four university students (93 women, 41 men) were administered the Vandenberg Mental Rotation Test and the Thurstone Word Fluency Test, and they were asked to report their Scholastic Achievement Test scores. Finger lengths were measured, because literature has reported gender differences in the ratio of the 2nd to 4th, 2nd to 3rd, and 2nd to 5th finger lengths, such that the ratio is larger in women than in men. The goal of this study was to evaluate the relations between finger-length ratios and cognitive skills, such as spatial skills and verbal fluency, which have shown gender differences and direct relations to hormonal effects. Gender differences were found in the expected directions, such that the men performed better than the women for mental rotation, the women performed better than the men for verbal fluency, and the finger-length ratios were in the directions reported in the literature. The finger-length ratios showed an interesting relation with the cognitive variables for the men and women. For the men, better performance on the measures, including mental rotation, verbal fluency, and verbal Scholastic Achievement Test score was associated with less of a male-typical finger-length ratio pattern, or higher ratios. For the women, better performance for mental rotation and verbal fluency was associated with less of a female-typical finger-length ratio pattern, or lower ratios. Thus, in this group of college students, better cognitive performance was associated with a less gender-typical finger-length ratio, for both men and women. These findings are discussed in the context of other similar reports and a possible curvilinear relation between hormones and cognition in normal populations.
TL;DR: Results indicated that there was communality in inhibitory task demands across instruments, although the specific pattern of task intercorrelations varied in children with high and low spans.
Abstract: A precise definition of executive control remains elusive, related in part to the variations among executive tasks in the nature of the task demands, which complicate the identification of test-specific versus construct-specific performance. In this study, tasks were chosen that varied in the nature of the stimulus (verbal, nonverbal), response (naming, somatic motor), conflict type (proactive interference, distraction), and inhibitory process (attention control, response suppression) required. Then performance differences were examined in 184 young children (age range = 3 years 6 months to 6 years 1 month), comparing those with high (5 or more digits) and low (3 or fewer digits) spans to determine the dependence on short-term memory. Results indicated that there was communality in inhibitory task demands across instruments, although the specific pattern of task intercorrelations varied in children with high and low spans. Furthermore, only performance on attention control tasks-that is, that require cognitive engagement/disengagement among an internally represented rule or response set that was previously active versus those currently active-differed between children of high and low spans. In contrast, there were differences neither between children with high and low spans on response suppression tasks nor on tasks when considered by type of stimulus, response, or conflict. Individual differences in well-regulated thought may rest in variations in the ability to maintain information in an active, quickly retrievable state that subserve controlling attention in a goal-relevant fashion.
TL;DR: This study addressed the widespread claims of a characteristic "WS cognitive profile" by looking for heterogeneity rather than homogeneity by using the Woodcock-Johnson Tests of Cognitive Ability-Revised to investigate a wide range of cognitive abilities in people with Williams syndrome.
Abstract: This study used the Woodcock-Johnson Tests of Cognitive Ability-Revised to investigate a wide range of cognitive abilities in people with Williams syndrome (WS). It involved a comparatively large sample of 31 people with WS, but took a case-series approach. The study addressed the widespread claims of a characteristic "WS cognitive profile" by looking for heterogeneity rather than homogeneity. People with WS showed a variety of preserved (significantly above mental age [MA]), expected (at MA), and significantly impaired (significantly below MA) levels of functioning. Such results provide clear evidence for heterogeneity in cognitive functions within WS. We found the most homogeneity on a test of phonological processing and a test of phonological short-term memory, with half of the WS sample performing at MA levels on these tests. Interestingly, no WS individual showed a weakness on a test of nonverbal reasoning, and only one WS individual showed a weakness on a test of verbal comprehension. In addition, we found that strengths on analysis-synthesis and verbal analogies occurred only for WS individuals with an MA less than 5.5 years (our sample median MA); people with an MA greater than 5.5 years performed at MA level on these 2 tests. Results also provided preliminary evidence for distinct subgroups of WS people based on their cognitive strengths and weaknesses on a broad range of cognitive functions. On the basis of the findings, caution should be made in declaring a single cognitive profile that is characteristic of all individuals with WS. Just as there is heterogeneity in genetic and physical anomalies within WS, not all WS individuals share the same cognitive strengths and weaknesses. Also, not all WS individuals show the profile of a strength in verbal abilities and a weakness in spatial functions.
TL;DR: Results did indicate global EF deficits in the combined group of children with HFA and AD, and specific deficits in flexibility and organization were most prominent within the EF domain.
Abstract: Executive function (EF) abilities were investigated in 72 children with high-functioning autism (HFA) spectrum disorders through the collection of parent ratings and performance on laboratory measures of EF. In addition, discrepancy analysis was used to isolate executive functioning on tasks that carry multiple demands. Comparison of HFA and Asperger Disorder (AD) groups did not reveal consistent differences in EF. Results did indicate global EF deficits in the combined group of children with HFA and AD. Within the EF domain, specific deficits in flexibility and organization were most prominent.
TL;DR: The pattern of findings suggests that ASD is associated with a profound deficit in automatic spatial attention abilities and abnormal voluntary spatial attentionabilities and a dysfunctional cerebello-frontal spatial attention system in ASD.
Abstract: This study investigated the functional neuroanatomical correlates of spatial attention impairments in autism spectrum disorders (ASD) using an event-related functional magnetic resonance imaging (FMRI) design. Eight ASD participants and 8 normal comparison (NC) participants were tested with a task that required stimulus discrimination following a spatial cue that preceded target presentation by 100 msec (short interstimulus interval [ISI]) or 800 msec (long ISI). The ASD group showed significant behavioral spatial attention impairment in the short ISI condition. The FMRI results showed a reduction in activity within frontal, parietal, and occipital regions in ASD relative to the NC group, most notably within the inferior parietal lobule. ASD behavioral performance improved in the long ISI condition but was still impaired relative to the NC group. ASD FMRI activity in the long ISI condition suggested that the rudimentary framework of normal attention networks were engaged in ASD including bilateral activation within the frontal, parietal, and occipital lobes. Notable activation increases were observed in the superior parietal lobule and extrastriate cortex. No reliable activation was observed in the posterior cerebellar vermis in ASD participants during either long or short ISI conditions. In addition, no frontal activation during short ISI and severely reduced frontal activation during long ISI was observed in the ASD group. Taken together, these findings suggest a dysfunctional cerebello-frontal spatial attention system in ASD. The pattern of findings suggests that ASD is associated with a profound deficit in automatic spatial attention abilities and abnormal voluntary spatial attention abilities. This article also describes a method for reducing the contribution of physical eye movements to the blood-oxygenation level dependent activity in studies of ASD.
TL;DR: In the possible AD patients as a group, the decrement in vigilance occurred in the absence of concurrent deficits on standard attentional tasks, such as the Stroop and Trail Making tests, suggesting that deficits in vigilance over time may appear earlier than deficits in selective attention.
Abstract: The vigilance decrement in perceptual sensitivity was examined in 10 patients with mild Alzheimer's disease (AD) and 20 age-matched controls. A visual high-event rate digit-discrimination task lasting 7.2 min. (six 1.2 min blocks) was presented at different levels of stimulus degradation. Previous studies have shown that sensitivity decrements (d') over time at high-stimulus degradation result from demands on effortful processing. For all degradation levels, the overall level of vigilance (d') was lower in AD patients than in controls. All participants showed sensitivity decrement over blocks, with greater decrement at higher degradation levels. AD patients exhibited greater sensitivity decrement over time at the highest degradation level they all could perform relative to control participants. There were no concomitant changes in either response bias (C) or response times. The results indicate that mild AD patients have overall lower levels of vigilance under conditions that require both automatic and effortful processing. Mild AD patients also exhibit a deficit in the maintenance of vigilance over time under effortful processing conditions. Although the sample of AD patients was small, results further suggest that both possible and probable AD patients had greater sensitivity decrement over time at the highest degradation level than did control participants, but only probable AD patients had lower overall levels of vigilance. In the possible AD patients as a group, the decrement in vigilance occurred in the absence of concurrent deficits on standard attentional tasks, such as the Stroop and Trail Making tests, suggesting that deficits in vigilance over time may appear earlier than deficits in selective attention.
TL;DR: The results suggest that both low IQ and fragile X status contribute to working memory limitations inGirls with fragile X and that EF inefficiency in girls with Turner syndrome is due to bothWorking memory limitations and slower response times.
Abstract: The aim of this study was to examine executive function (EF) skills in girls with fragile X or Turner syndrome, using the Contingency Naming Test (CNT). The CNT is a Stroop-like task involving a 1- or 2-attribute contingency rule. We predicted that girls with fragile X would make errors reflecting poor cognitive flexibility and working memory limitations. We predicted that girls with Turner syndrome would have sufficient cognitive flexibility to perform the CNT accurately, but would have difficulty with verbal inhibition and would thus make more self-corrections than girls in a comparison group. The hypotheses were partially supported: relative to their Full Scale IQ-matched comparison group, girls with fragile X or Turner syndrome were slower on the warm-up naming task; girls with fragile X made more errors on the 1-attribute task, and girls with Turner syndrome were less efficient on both the 1- and 2-attribute tasks, without making more self-corrections. These results support previous findings of execu...
TL;DR: Results for children were consistent with past adult studies in showing a significantly larger ERN only to erroneous responses in both the alone and the audience groups.
Abstract: This research assessed the effect of an observer upon error-related negativity (ERN) in 20 children (ages 7–11): 9 worked alone and 11 worked under the observation of a friend of theirs (alone/audience groups). Erroneous motor responses were recorded to Go and No-Go visual stimuli (triangles in different orientations) at three brain sites (Fz, Cz, and Pz). Results for children were consistent with past adult studies in showing a significantly larger ERN only to erroneous responses in both the alone and the audience groups. Children in the audience group produced larger ERNs than those in the alone group. Furthermore, older children (ages 9–11) produced larger ERNs than younger children (ages 7–8) in both groups. These findings were discussed in the context of an action monitoring system that regulates responses, detects errors, and entrains affective responses associated with correct and incorrect responses.
TL;DR: The study compared performance of children with high levels of attention deficit hyperactivity disorder, children with ADHD and oppositional defiant disorder, and a control group on a Go-No-go test in a self-paced and computer-paced condition.
Abstract: The study compared performance of children with high levels of attention deficit hyperactivity disorder (ADHD; n = 22), children with ADHD and oppositional defiant disorder (ODD; n = 19), and a control group (n = 20) on a Go-No-go test in a self-paced and computer-paced condition. Each condition, in turn, was run in a reward and a nonreward condition. The children were recruited through screening of a school population without ADHD or ODD (N = 450). Findings indicated that children having high levels of ADHD plus ODD showed poor impulse control in all 4 conditions. No poor impulse control was found in the group with high levels of ADHD. This group demonstrated slower RTs across the computer-paced conditions. Findings were discussed in terms of the response-inhibition hypothesis, as formulated by Barkley (1997), the delay-aversion theory (Sonuga-Barke, 1995), and the state-regulation theory (Van der Meere, 2002).
TL;DR: This study investigated reasons why children with attention deficit hyperactivity disorder (ADHD) or arithmetic learning disorder (ALD) have difficulties in solving arithmetic word problems to verify whether these difficulties are due to a working memory deficit and defective inhibition of irrelevant information included in the problem wording.
Abstract: This study investigated reasons why children with attention deficit hyperactivity disorder (ADHD) or arithmetic learning disorder (ALD) have difficulties in solving arithmetic word problems. In particular, the aim of this study was to verify whether these difficulties are due to a working memory deficit and defective inhibition of irrelevant information included in the problem wording. Furthermore, the study was geared to test whether children with ADHD or ALD have a specific disability in recalling and handling numerical or literal information. In an attempt to provide an answer to these questions, three groups of children were tested: children with ADHD, children with ALD, and a group of children achieving at normal levels. They were presented with a battery of arithmetic word problems containing irrelevant information (using either numerical or literal information). Children were asked to recall relevant information within the texts and then solve the problems. Children with ADHD recalled significantly...
TL;DR: Findings support the use of performance-based assessment of executive control skills in preschoolers suspected of having ADHD, and suggest the ACPT-–P may be particularly useful in assessing sustained attention and response preparation and may complement behavior rating scales.
Abstract: Development of diagnostic instruments directed toward neuropsychological assessment of preschoolers lags significantly behind those available for school-age children (DeWolfe, Byrne, & Bawden, 2000). This is particularly true for measures of executive function (EF). The Auditory Continuous Performance Test for Preschoolers (ACPT-P; Mahone, Pillion, & Hiemenz, 2001) is a computerized, Go-No-go test developed to measure selected EF skills in preschoolers. First, to determine whether performance on the ACPT-P is associated with hearing impairment, we compared performance of children with mild hearing loss (MHL) to controls on the ACPT-P, and measures of spatial working memory (SWM) and motor persistence (MP). There were no differences between performance of the MHL group and controls on any of these measures. Second, to examine the construct validity of the ACPT-P, we compared performance of 40 preschoolers with ADHD to 40 age- and sex-matched controls, using the ACPT-P to measure response preparation, sustained attention, and inhibitory control. We also compared these groups on measures of SWM and MP. The group with attention deficit hyperactivity disorder (ADHD) performed significantly worse than controls on the ACPT-P (omissions, mean response time, variability) and MP. The ACPT-P was correlated with the MP, but not with the SWM measure. Both the ACPT-P and the MP measures showed low to moderate correlations with parent ratings of behavior associated with ADHD. These findings support the use of performance-based assessment of executive control skills in preschoolers suspected of having ADHD. In this age group, the ACPT-P may be particularly useful in assessing sustained attention and response preparation and may complement behavior rating scales.
TL;DR: Current research findings concerning EFs in preschoolers, children, adolescents, and adults with attention deficit hyperactivity disorder (ADHD), taking into account, gender, comorbidity, genetic, and physiological findings are presented.
Abstract: Executive function (EF) is a complex construct that can be broadly defined as higher order cognitive abilities that allow for strategic planning, cognitive flexibility, self-regulation, and goal-directed behavior. This broad, multidimensional view of EFs is problematic from a measurement perspective and has rightly been criticized by researchers such as Pennington and Ozonoff (1996) who noted, “in both neuropsychology and cognitive psychology, the definition of EFs is provisional and under-specified” (p. 55). Nevertheless, a plethora of studies have investigated EFs in clinical and nonclinical samples, and numerous definitions of this construct exist in the literature. These definitions tend to differ with respect to the degree of emphasis placed on control processes (e.g., Denckla, 1996), working memory (e.g., Pennington, Bennetto, McAleer, & Roberts, 1996), strategic planning (Welsh & Pennington, 1988), behavioral inhibition (Barkley, 1997), and other components thought to be part of EF. In a previous special issue of Developmental Neuropsychology concerning EFs, Fletcher (1996) pointed out that EFs are difficult to define and require careful operationalization, and measures of EF are factorially complex, but the components can be separated and measured. The purpose of this special issue is to present current research findings concerning EFs in preschoolers, children, adolescents, and adults with attention deficit hyperactivity disorder (ADHD), taking into account, gender, comorbidity, genetic, and physiological findings. Research across a variety of disciplines, including genetic, behavioral, neuropsychological, neurometabolite, DEVELOPMENTAL NEUROPSYCHOLOGY, 27(1), 1–10 Copyright © 2005, Lawrence Erlbaum Associates, Inc.
TL;DR: Children who experience traumatic brain injury (TBI) often show cognitive impairments postinjury, some of which recover over time, and growth curve analyses showed an initial impairment in response inhibition and improvement over the 2 years following injury.
Abstract: Children who experience traumatic brain injury (TBI) often show cognitive impairments postinjury, some of which recover over time. We examined the recovery of motor response inhibition immediately following TBI and over 2 years. We assessed the role of injury severity, age at injury, and lesion characteristics on initial impairment and recovery while considering the role of pre-injury psychiatric disorder. Participants were 136 children with TBI aged 5-16 years. Latency of motor response inhibition was measured with the stop-signal task within 1 month of the injury and again at 3, 6, 12, and 24 months. The performance of the TBI participants at each measurement occasion was standardized with 117 children of similar age, but without injury. Residualized latency scores were calculated. Growth curve analyses showed an initial impairment in response inhibition and improvement over the 2 years following injury. Younger TBI patients were initially more impaired although they exhibited greater recovery of response inhibition than did older TBI patients. Longer duration of coma, but not reactivity of pupils or Glasgow Coma Scale score, predicted initial deficit. Lesion characteristics or pre-injury attention deficit hyperactivity disorder did not predict initial impairment or recovery. Replication with longitudinal testing of a comparison group of children sustaining extracranial injury is necessary to confirm our findings.
TL;DR: Sex differences in cognitive functioning were investigated in children with velocardiofacial syndrome (VCFS), a genetic defect caused by a microdeletion on chromosome 22q, and it is indicated that boys with VCFS may be more cognitively affected than girls.
Abstract: Sex differences in cognitive functioning were investigated in children with velocardiofacial syndrome (VCFS), a genetic defect caused by a microdeletion on chromosome 22q.11. The study population consisted of six groups: 50 boys with VCFS (M = 11.1, SD = 2.7), 40 girls with VCFS (M = 10.8, SD = 2.5), 13 male siblings of the participant with VCFS (M = 12.3, SD = 1.9), 17 female siblings of the participant with VCFS (M = 12.2, SD = 1.9), and a race- and gender-ratio-matched sample of 28 boy community control participants (M = 10.7, SD =2.4) and 19 girl community control participants (M = 9.2, SD =2.3). Each participant received a psychological assessment including intellectual and academic achievement as well as structural magnetic resonance imaging of his or her brain. Our results indicate that boys with VCFS may be more cognitively affected than girls. In addition, and although cross-sectional in nature, our results document a negative association between age and cognitive functioning in girls with VCFS but not in boys. Sex differences in frontal lobe volume are generally seen in the general population between boys and girls (boys > girls) and across all three samples, this trend emerged. Relative to boys with VCFS, girls with VCFS may be less cognitively affected, although age is negatively associated with cognitive functioning in girls with VCFS but not boys, suggesting that girls with VCFS may fail to maintain this cognitive advantage over boys.