Executive functions in dyslexia.

This study focused on executive functions in dyslexia. A group of 43 heavily-affected young dyslexics, divided into two groups based on the results of a receptive language test, and 20 non-dyslexic controls, were tested with a Dichotic Listening Test, the Stroop Color Word Test and the Wisconsin Card Sorting Test. The dyslexic subjects demonstrated significant impairment on all tasks, but with different patterns of impairment according to the subgrouping. The subgroups were equally impaired on the Dichotic Listening Test, but differed on the Stroop and the Wisconsin Tests. The data support a hypothesis suggesting executive problems in dyslexia, depending on receptive language skills.     

Executive dysfunction as a risk marker for substance abuse: The role of impulsive personality traits

The relationships between family history of substance use, executive functions, impaired decision making, and current substance dependence are the focus of this study. Thirty-eight substance-dependent inpatients were compared with 30 community controls on performance on the Wisconsin Card Sorting Test, Trail-Making Test-B, the Stroop Color Word Test, the Wais-II Digit Span, and the Iowa Gambling Task. Recent alcohol use, depressive symptoms, and impulsivity were also assessed. As hypothesized, individuals with substance dependence exhibited poorer executive functioning. Family history status was modestly related to impaired performance on tests designed to measure the integrity of the dorsolateral prefrontal cortex. In particular, substance-dependent, family history positive individuals performed less well on the Wisconsin Card Sorting Test than substance-dependent individuals without a family history. Digit Span performances were worse among family history positive controls when compared with family history negative controls. Impulsive personality traits—specifically, difficulty thinking before acting (Urgency)—were related, as hypothesized, to executive functioning. Results indicate that family history status confers an increased risk of impairment beyond that conferred by recent substance abuse, and that impulsive personality traits are related to performance on tests of executive functions. Implications for criminality are discussed. Copyright © 2008 John Wiley & Sons, Ltd.     

The influence of functional social support on executive functioning in middle-aged African Americans

ABSTRACT

Social support has a positive influence on cognitive functioning and buffers cognitive decline in older adults. This study examined the relations between social support and executive functioning in middle-aged adults. A community-based sample of African Americans completed the Interpersonal Support Evaluation List, a measure of functions of social support, and two measures of executive functioning, the Stroop Color and Word Test and the Wisconsin Card Sorting Test (WCST). Hierarchical regression analyses were used to explore the hypothesis that different facets of perceived social support influence performance on measures of executive functioning. After controlling for age, gender, and education, social support facets including belonging support, selfesteem support, appraisal support, and tangible support were significant predictors of Stroop performance. In addition, tangible support significantly predicted WCST performance. These findings add to previous literature on social support and cognition; however, findings for middle-aged adults are unique and suggest that social support has a positive influence on some executive functions in African Americans prior to old age.     

Executive Functioning in Children and Adolescents with Major Depressive Disorder

The present investigation examined neurocognitive functioning, focusing on executive functioning (EF), in 39 children and adolescents with Major Depressive Disorder (MDD) and 24 healthy control subjects all ages 8 to 17 years. The Wechsler Intelligence Scale for Children-Third Edition along with several measures of executive functioning including the Wisconsin Card Sorting Task, Trail Making Test, Controlled Oral Word Association Test, and the Stroop Color Word Test were administered. The neurocognitive profiles for the group of depressed children and adolescents were grossly intact as most scores on intellectual and EF measures fell within the average range and did not differ from the comparison group. Mental processing speed was decreased in the MDD versus normal control group and 27% of the depressed group performed below average on the Trail Making Test. This investigation provided a good base from which to compare future literature on EF in outpatients with early-onset MDD.     

The influence of functional social support on executive functioning in middle-aged African Americans

Social support has a positive influence on cognitive functioning and buffers cognitive decline in older adults. This study examined the relations between social support and executive functioning in middle-aged adults. A community-based sample of African Americans completed the Interpersonal Support Evaluation List, a measure of functions of social support, and two measures of executive functioning, the Stroop Color and Word Test and the Wisconsin Card Sorting Test (WCST). Hierarchical regression analyses were used to explore the hypothesis that different facets of perceived social support influence performance on measures of executive functioning. After controlling for age, gender, and education, social support facets including belonging support, self-esteem support, appraisal support, and tangible support were significant predictors of Stroop performance. In addition, tangible support significantly predicted WCST performance. These findings add to previous literature on social support and cognition; however, findings for middle-aged adults are unique and suggest that social support has a positive influence on some executive functions in African Americans prior to old age.     

Executive function tests in early‐onset psychosis: which one to choose?

People with schizophrenia exhibit executive functioning deficits, an area well investigated in the adult onset schizophrenia (AOS) group, but far less so in early-onset schizophrenia (EOS). Since EOS in general seems to exhibit poorer cognitive functions and is clinically more compromised than AOS, choice of efficient and sensitive assessment measures is not necessarily the same within the two groups. The MATRICS Consensus Cognitive Battery was developed for adults when studying treatment effects and uses Mazes (Neuropsychological Assessment Battery [NAB]) to assess executive functioning. We tested 31 adolescents with schizophrenia spectrum disorders and 66 healthy controls in order to examine how Mazes compares to two other commonly used tests to measure executive functioning, D-KEFS Color Word Interference Test (Stroop) and the Wisconsin Card Sorting Test (WCST). Significant discriminating power was found for all three measures. Patients performed 0.8-1.5 SD below controls with Stroop as the most sensitive measure, followed by Mazes and WCST. Mazes was selected by the MATRICS to assess treatment effects in AOS and is shown to be able. We find the instrument also able to separate adolescent patients from controls and thus, it appears a sensible choice in clinical settings. If a more elaborated neuropsychological evaluation of the executive functioning domain is needed, Stroop should be considered a complementary test.     

When prejudice does not pay: effects of interracial contact on executive function

Abstract - This study examined the influence of interracial interaction on the cognitive functioning of members of a dominant racial group. White participants had a brief interaction with either a White or a Black confederate, and then completed an ostensibly unrelated Stroop color-naming test. Prior to the interaction, participants' racial attitudes regarding Whites and Blacks were measured via the Implicit Association Test. Racial attitudes were predictive of impairment on the Stroop test for individuals who participated in interracial interactions, but not for those who participated in same-race interactions. The results are consistent with recently proposed resource models of self-regulation and executive control in that interracial interaction, a particularly taxing exercise of self-regulation for highly prejudiced individuals, negatively affected performance on a subsequent, yet unrelated, test of executive function.     

Prediction of fine motor skills of children having language and speech disorders

Relationships between the fine motor skills and linguistic abilities of 37 developmentally delayed children, ages 5 to 9 yr., were studied using a battery of expressive and receptive language tests, a measure of fine motor performance, a dichotic listening test, and individual intelligence tests. While IQs and MAs were not related to fine motor skills, both expressive and receptive language test scores showed moderate to moderately high correlations, the highest single relationship being the Test for the Auditory Comprehension of Language. In concert with CAs, a dichotic right-ear test score, the Auditory Comprehension Test, predicted fine motor-skill indices substantially; R = .80. Strong relationships appear between linguistic and fine motor skills in an age group not previously investigated and at higher levels than reported in studies of infants and very young children. Dichotic results were abnormal in a majority of the children.     

Assessment of executive functions in a Brazilian sample of bipolar subjects

Research has demonstrated impairments in executive functions in Bipolar Mood Disorder patients. Evidence shows that this impairment is present in both periods of active symptoms of the disorder, as well as euthymic stages, and is compounded by mood episodes, especially manic phases. The purpose of this study was to compare the executive performance of a sample of Brazilian bipolar patients in depressive episodes, (44 participants), euthymia (37 participants), and in controls (43 participants). The main instrument for evaluation was the Wisconsin Card Sorting Test. Significant differences were found in performance on the Wisconsin Card Sorting Test between Bipolar subjects (Type I) (both in depression and euthymia) and the controls. No significant correlations were found between the number of manic episodes and the performance on execute measurement variables. The findings suggest that the executive dysfunctions in Bipolar Disorder may be related to both transitory and permanent deficits.     

Executive functioning in older adults with mild cognitive impairment: MCI has effects on planning, but not on inhibition

In this study, we compared executive functioning in 32 mild cognitive impairment (MCI) individuals with that of normally aging controls. Cognitive planning tests (Trail Making, Porteus Maze Test, verbal fluency tests) show a group difference favoring the normal controls, but tests for inhibition of prepotent responses (no-go accuracy, two measures of the Stroop effect, and negative priming) failed to uncover a significant group difference. The results indicate that there is no general executive control function impairment in MCI; rather, the deficits found are compatible with the hypothesis that MCI is an accelerated form of normal aging.     

The frontal hypothesis of cognitive aging: factor structure and age effects on four frontal tests among healthy individuals

With 101 healthy aging adult participants, the authors investigated whether executive functions are a unitary concept. The authors established the factor structure of the Wisconsin Card Sorting Test (WCST; E. A. Berg, 1948), the Stroop color and word test (C. J. Golden, 1978), verbal fluency using the Controlled Oral Word Association Test (COWAT; Benton, 1967), and the Digits Backwards subtest of the Wechsler Adult Intelligence Scale-Revised (WAIS-R; D. Wechsler, 1981). The authors also evaluated the extent to which age and other demographic variables predicted common underlying properties of these frontal tests. Results revealed an age-related decline in executive abilities differentially reflected by the selected tasks. These data suggest caution using the COWAT to evaluate executive abilities in older people. The authors interpret findings to support the unitary view of executive abilities and the executive decline proposed by the frontal hypothesis.     

Executive Functioning in Older Adults with Mild Cognitive Impairment: MCI Has Effects on Planning,But Not on Inhibition

ABSTRACT

In this study, we compared executive functioning in 32 mild cognitive impairment (MCI) individuals with that of normally aging controls. Cognitive planning tests (Trail Making, Porteus Maze Test, verbal fluency tests) show a group difference favoring the normal controls, but tests for inhibition of prepotent responses (no-go accuracy, two measures of the Stroop effect, and negative priming) failed to uncover a significant group difference. The results indicate that there is no general executive control function impairment in MCI; rather, the deficits found are compatible with the hypothesis that MCI is an accelerated form of normal aging.     

Executive functions in children with Autism Spectrum Disorders

Executive dysfunction is a characteristic impairment of individuals with Autism Spectrum Disorders (ASD). However whether such deficits are related to autism per se, or to associated intellectual disability is unclear. This paper examines executive functions in a group of children with ASD (N = 54, all IQ?70) in relation to a typically developing control group individually matched on the basis of age, gender, IQ and vocabulary. Significant impairments in the inhibition of prepotent responses (Stroop, Junior Hayling Test) and planning (Tower of London) were reported for children with ASD, with preserved performance for mental flexibility (Wisconsin Card Sorting Task) and generativity (Verbal Fluency). Atypical age-related patterns of performance were reported on tasks tapping response inhibition and self-monitoring for children with ASD compared to controls. The disparity between these and previous research findings are discussed. A multidimensional notion of executive functions is proposed, with difficulties in planning, the inhibition of prepotent responses and self-monitoring reflecting characteristic features of ASD that are independent of IQ and verbal ability, and relatively stable across the childhood years.     

Executive functions in children with Autism Spectrum Disorders

Executive dysfunction is a characteristic impairment of individuals with Autism Spectrum Disorders (ASD). However whether such deficits are related to autism per se, or to associated intellectual disability is unclear. This paper examines executive functions in a group of children with ASD (N = 54, all IQ⩾70) in relation to a typically developing control group individually matched on the basis of age, gender, IQ and vocabulary. Significant impairments in the inhibition of prepotent responses (Stroop, Junior Hayling Test) and planning (Tower of London) were reported for children with ASD, with preserved performance for mental flexibility (Wisconsin Card Sorting Task) and generativity (Verbal Fluency). Atypical age-related patterns of performance were reported on tasks tapping response inhibition and self-monitoring for children with ASD compared to controls. The disparity between these and previous research findings are discussed. A multidimensional notion of executive functions is proposed, with difficulties in planning, the inhibition of prepotent responses and self-monitoring reflecting characteristic features of ASD that are independent of IQ and verbal ability, and relatively stable across the childhood years.     

“各说各话”的语言经验对景颇族大学生执行功能的影响

在中国云南的景颇族中,相当多的家庭是由不同支系的人组成的,家庭成员交际时存在着"各说各话"的现象。"各说各话"对讲话者的执行功能有无影响?采用抑制控制、注意转换和记忆刷新任务测量各说各话和非各说各话的景颇族大学生的抑制能力、转换能力和刷新能力。结果表明,各说各话与非各说各话的景颇族大学生在色词干扰和数字转换中差异显著,各说各话者的Stroop效应量小,停止信号的反应时短。各说各话与非各说各话的景颇族大学生在数字转换和图形转换中差异显著,各说各话者反应快,转换代价小。各说各话与非各说各话的景颇族大学生在活动记忆刷新与色点位置刷新任务中差异不显著。这表明,各说各话者比非各说各话者在抑制能力与转换能力上具有优势。语言经验对执行功能的影响具有功能特异性。     

Poor readers but compelled to read: Stroop effects in developmental dyslexia.

We studied a group of 24 children with dyslexia in second to fifth primary school grades by using a discrete-trial computerized version of the Stroop Color-Word Test. Since the classic Stroop effect depends on the interference of reading with color naming, one would expect these children to show no interference or, at least, less interference than normal readers. Children with dyslexia showed, however, a Stroop effect larger than normal readers of the same age. This suggests that reading, although difficult and slow, is an inescapable step that precedes naming both in poor and in normal readers.     

Poor Readers but Compelled to Read: Stroop Effects in Developmental Dyslexia

We studied a group of 24 children with dyslexia in second to fifth primary school grades by using a discrete-trial computerized version of the Stroop Color-Word Test. Since the classic Stroop effect depends on the interference of reading with color naming, one would expect these children to show no interference or, at least, less interference than normal readers. Children with dyslexia showed, however, a Stroop effect larger than normal readers of the same age. This suggests that reading, although difficult and slow, is an inescapable step that precedes naming both in poor and in normal readers.     

语音记忆和中央执行功能在不同年级儿童解码和语言理解中的作用

选取256名三~六年级儿童, 采用相关分析、结构方程模型等方法考察了语音记忆和中央执行功能在不同年级儿童的解码和语言理解中的作用。结果显示, 在低年级阶段, 语音记忆和刷新对解码存在显著预测作用, 转换和刷新对语言理解存在显著预测作用; 在高年级阶段, 只有刷新对解码保持着稳定的预测作用。这表明, 语音记忆和中央执行功能对儿童的解码和语言理解存在不同的影响, 并且这种影响会随着年级的增长发生变化。     

Cerebral dominance in aphasia recovery.

This investigation studied the patterns of ear preference of a group of 25 aphasic adults through the administration of two verbal dichotic tests and retests over a 2-month interval of time. These dichotic tests were a Dichotic Digits Test (DDT) and a Dichotic Animal Names Test (DANT). Schuell's short test of aphasia was given twice over this interval to assess language recovery. Results indicated that as aphasics improve in language, cerebral dominance becomes more firmly established in the right cerebral hemisphere. The data in this study tend to support a dominance shift hypothesis in the recovery of language after aphasia.     

Validation of distinct amnesic and executive type memory deficit in a psychiatric sample based on retrieval performance

Studies of localized brain dysfunctions have revealed connections between patterns of cognitive dysfunction and specific profiles of memory impairment. The amnesic type of memory impairment is defined by deficits in both free recall and recognition memory, whereas the dysexecutive memory impairment is characterized by retrieval deficits, i.e. a disproportional impairment in free recall relative to recognition memory. The present study tests whether classifications of psychiatric patients into recall impaired only (= RO group) and Recall and Recognition impaired (= RR group) correspond to the executive type and amnesic type of memory impairment. The alternative hypothesis is that the two groups merely differ in degree of neuropsychological and psychiatric disturbance. Forty-four subjects impaired on California Verbal Learning Test (CVLT) were selected from a larger database of 103 impaired and non-impaired subjects with schizophrenia or recurrent major depression. Subjects were classified into RO and RR groups and compared on measures of memory strategy (recency effect and interference on CVLT), overall neuropsychological function (Stroop Test and WAIS-R similarity) and psychiatric symptom load (positive and negative symptoms). Repeated measures ANOVA showed no effects of group, i.e. the RR group did not perform consistently below the RO group with regard to memory strategy, neuropsychological function or psychiatric symptom load. Two out of three analyses showed group x test interaction, supporting the dissociation of distinct executive and amnesic profiles among psychiatric patients. The RO group was more susceptible to interference but had better recency score than the RR group. The RO had higher negative symptoms while the RR group had higher positive symptoms.