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Objective: Attention and executive function (EF) deficits are ubiquitous in neurodevelopmental disorders including Attention Deficit/Hyperactivity Disorder (ADHD), as are high levels of intraindividual variability (IIV). Attention and EF are typically assessed using informant ratings and objective measures; however, discrepancies between different metrics often make it difficult to fully characterize a child's attention capabilities, and IIV has been proposed as a potentially useful discriminator. Our objective was to explore the relationship between IIV, using the residualized intraindividual standard deviation (rISD) method, and informant ratings of attention and EF in a mixed pediatric sample, to determine the potential utility of IIV for aiding attention diagnostics. Another commonly used, though controversial, IIV indicator, the coefficient of variation (ICV), was calculated for comparison purposes. Method: We assessed 51 children with varying degrees of attention and EF deficits. Measures included parent and teacher responses on the Comprehensive Executive Function Inventory (CEFI) and response times (RT) on a go/no-go task, which were used to estimate IIV. Results: Mean RT, rISD, and ICV were significantly related to parent and teacher ratings of attention, though ICV showed a relatively weaker association. rISD also showed associations with parent ratings of working memory and self-monitoring, as well as teacher ratings of working memory. Conclusion: The significant, and relatively stronger, relationship between rISD and parent and teacher ratings of attention supports the use of this metric, compared to mean RT and ICV. The rISD indicator of IIV thus shows potential utility as a unique and objective measure of attention in children across various neurodevelopmental disorders and, with additional research, may prove useful for diagnosis of attention problems.

Executive functions (EFs) have been assessed with performance-based measures and rating scales. Research has shown a lack of association between these two methods. One factor that might contribute to this difference is the structure provided on performance-based measures that is not provided on rating scales. This study examined the role of structure on self-directed task completion, an aspect of EF, using a novel unstructured performance-based task (UPT).Children aged 8-12 years (38 attention-deficit/hyperactivity disorder, ADHD; 42 typically developing) and their caregivers participated. We compared performance on the UPT, performance-based measures of EF (Stroop test and Trail-Making Test), and a rating scale to assess EF (Barkley Deficits in Executive Functioning Scale-Children and Adolescents, BDEFS-CA).Group differences were found across all measures. Significant associations emerged between the UPT and Stroop test, Trail-Making Test, and BDEFS-CA, but no significant associations were found between the Stroop test or Trail-Making Test and the BDEFS-CA. In regression analyses, performance-based tasks and the rating scale both uniquely predicted UPT performance. The UPT was a significant predictor of group status when entered with performance-based tasks, but the UPT did not enter as a significant predictor when entered with the rating scale.The UPT is a promising measure to assess self-directed task completion in children with ADHD.

The Delis-Kaplan Executive Function System (D-KEFS) is a battery of tests designed to measure executive functions (EF). Additionally, the D-KEFS contains lower-order tasks, designed to control for speed of visual scanning, sequencing, and verbal and graphomotor output. The construct and criterion validities of D-KEFS scores that areParticipants were 427 adults (18-93 years) who completed the timed subtests of the D-KEFS. Four hundred two participants also completed the Push-Turn-Taptap (PTT; a separate measure of EF) to allow cross-validation.General linear regressions showed that D-KEFS errors committed on the EF tests were associated with EF timed performance (assessed using the D-KEFS time-based scores and the PTT), but only among older adults. Importantly, errors committed on the D-KEFS tasks of lower-order processes were also associated with D-KEFS time-based EF performance, and this relationship held across the adult lifespan.These findings suggest that among older adults EF errors on the D-KEFS can be interpreted as indices of EF, but such interpretations are not automatically warranted for younger adults. Additionally, errors committed on non-EF tasks contained within the D-KEFS battery can be interpreted as reflecting EF weaknesses across the adult lifespan.

INTRODUCTION: African-Americans (AAs) are 64% more likely to be diagnosed with AD than non-Hispanic Whites. AAs with elevated AD biomarkers exhibit greater neurodegeneration in AD signature regions compared to non-Hispanic Whites with elevated AD biomarkers. This pilot trial examined whether normal or elevated plasma levels of interleukin (IL)-10 are associated with changes in executive function and short-term memory in AA women at risk for developing AD due to parental history. METHOD: Observational study comparing groups with elevated and normal plasma IL-10 levels. Study included 31 AA women (age=58.9±8 years) with parental history of AD. Measures included inflammatory blood biomarkers, executive function and visuospatial short-term memory tests. Multivariate linear regression with adjustment for comorbidities, and Bonferroni corrections for multiple comparisons were used to compare groups. Effect sizes (Cohen’s d) were generated. Using endpoints with moderate-large effects between groups, Pearson correlations determined associations between biomarker levels and cognitive performance. RESULTS: The elevated IL-10 group performed worse on the Trail-Making Test proportional score ((B-A)/A) (effect size (d =−0.87 (−1.6, −.1)). Moderate effects with large confident intervals were noted in inhibition, set-switching, and body position spatial memory. Significant differences between groups in levels of other inflammatory markers were noted, including IL-7 (p=0.002) and interferon γ (p=0.02). IL-7 remained significant after Bonferroni correction. Correlation matrices revealed moderate-large, significant correlations (yet with wide confidence intervals) between levels of IL-10 and IL-9 with BPST total correct trials, and between interferon γ and delayed recall. CONCLUSIONS: Interleukins may incite inflammation, leading to impaired aspects of executive function and short-term memory in this sample of African American women at risk for developing AD. This research provides effect sizes that will be used to power future research that will further investigate the relationship between inflammation, AD biomarkers, and cognitive function in an understudied population.

Everyday functioning and its executive functioning cognitive correlates (i.e., switching, inhibition, and updating) were investigated in healthy older adults (HOAs) using multiple methods of functional status. In addition to whether computerized experimental tasks would better dissociate these subcomponents than neuropsychological measures of executive functioning, we were also interested in the contributions of both experimental and neuropsychological measures of executive function subcomponents to functional abilities. Seventy HOAs (45 young-old and 25 old-old) and 70 younger adults completed executive function and neuropsychological tests. In addition to self- and informant questionnaires of functional abilities, HOAs completed two performance-based measures. An aging effect was found on all executive function measures. Old-old older adults and their informants did not report more functional difficulties but demonstrated more difficulties on performance-based measures relative to young-old participants. For the HOAs, after controlling for age and education, the neuropsychological measures of executive functioning, but not experimental measures, explained a significant amount of variance in the informant-report and both performance-based measures. Updating measures differentially predicted performance-based measures, while switching was important for questionnaire and performance-based measures. The contribution of executive functioning to functional status when measured with experimental measures specifically designed to isolate the executive subcomponent was not as strong as hypothesized. Further research examining the value of isolating executive function subcomponents in neuropsychological assessment and the prediction of functional abilities in older adults is warranted.

The experience of cognitive deficits and emotional dysfunction are prevalent in people with multiple sclerosis (PwMS), although research examining their interaction has provided inconsistent findings. The current study examined the ability of executive function to predict psychosocial adjustment in PwMS. One hundred and seven PwMS underwent cognitive assessment and completed measures of stress, depression, anxiety, and quality of life (QoL). There was limited support for a relationship. There was no relationship between objective cognitive tasks and state or trait anxiety, mental health QoL, overall QoL, or stress frequency. The only relationship with depression was found when the Beck Depression Inventory Fast-Screen was used, with a task of planning when the timing element was removed. A measure of error rates on a task of cognitive flexibility predicted physical health QoL, and severity, but not frequency, of stress was predicted by a task of working memory. The results of this study highlight the need for further research into the relationship between cognitive deficits and psychosocial adjustment because of the conflicting findings between studies and call for a common measurement framework for future investigation.

Executive function deficits are prevalent in people with multiple sclerosis (PwMS), and PwMS use less adaptive coping than healthy controls. This cross-sectional study assessed whether there is a relationship between executive function and coping in PwMS.One hundred and seven participants with relapsing remitting or secondary progressive MS (n = 83 and 24, respectively; age M = 48.8 ± 11.1 years) completed measures of coping and executive function.A positive relationship was found between verbal fluency and use of active, emotional, and instrumental social support coping, and total executive function and substance abuse coping. There was a negative relationship between coping strategies and core (social support, acceptance, religion, restraint, and total coping), higher order (denial and humor), and total executive function indices (acceptance, religion, behavioral disengagement, denial, and total coping).These directional differences provide support for the importance of specific executive functions in coping strategy utilization. Understanding these relationships will assist psychologists and neuropsychologists with patient psychoeducation, adaptive coping strategy intervention and management for PwMS with reduced executive function ability.

Little is known about the influence of multiple sclerosis (MS) on the regulation of emotion. The current study tested whether people with MS report more emotion regulation difficulties than healthy controls. The relationship between emotion regulation and other important variables (mood, quality of life, and executive function) was explored. Mediation models were used to further understand the links between emotion regulation, depressed mood, and executive function in MS.A total of 31 people with MS and 31 controls completed the Difficulties in Emotion Regulation Scales and measures of executive function (fluency and a go/no-go task), mood (Hospital Anxiety and Depression Scales), and a multidimensional assessment of quality of life (World Health Organization Quality of Life, brief version).People with MS reported experiencing more difficulties in emotion regulation than controls. Mediation analyses indicated that depression mediated the emotion regulation difficulties in MS, while executive dysfunction did not. Difficulties in emotion regulation predicted poorer psychological and social quality of life in MS, independent of problems with executive function.People with MS experience difficulties in emotion regulation, which predict poorer quality of life. These results indicate that emotional control skills should be investigated in further detail when considering interventions to enhance well-being in MS.

Olfactory dysfunction (OD) has been suggested as a possible marker of executive function (EF) deficits after traumatic brain injury (TBI) in adults. Little is known about the relationship between EF and OD in pediatric TBI (pTBI). This study aimed to investigate EF, explore the relationship between OD and EF, and determine the utility of olfactory performance as a marker of later EF in pTBI. It was hypothesized that (i) children with TBI would perform more poorly on EF measures relative to normative expectation; (ii) children with OD would perform more poorly on tests of EF than those with normal olfaction after TBI; and (iii) acute olfactory function would predict later EF for children with TBI.This was a prospective longitudinal study. Twenty seven children aged 8-16 with TBI completed olfactory assessment using the University of Pennsylvania Smell Identification Test at 0-3, 8 and 18 months post injury. Assessment of EF occurred at 8 and 18 month follow-up.At 8 month follow-up the pTBI cohort did not demonstrate a consistent pattern of impairment in EF, contrary to our first hypothesis. Children with OD showed significantly poorer performance on a single EF measure of Fluency when compared to those with normal olfaction at 8 months post injury, partially supporting our second hypothesis. Acute olfactory function did not significantly predict EF outcomes at either 8 or 18 months post injury.Overall our findings provide little support for a significant relationship between EF and OD in pTBI. In particular, there was no strong evidence that acute olfactory function is an accurate predictor of later EF in pTBI. Given the dearth of pediatric research, the limitations of our study and the potential significance of acute olfactory performance as an early marker of later EF deficits in children, further investigation is warranted.

The depression–executive dysfunction syndrome, a late-onset depression of vascular origin with executive dysfunction and psychomotor retardation, has also been described after stroke. We verified whether this syndrome also occurs in nonelderly stroke patients by investigating the association between domains of depressive symptoms with executive functions in 87 first-ever ischemic stroke patients. The retardation domain of the 31-item Hamilton Rating Scale for Depression was associated with decreased performance on verbal fluency (assessed with FAS). The association was maintained for younger patients (aged

Apart from motor symptoms, Parkinson's disease is characterized by executive and memory problems that have been observed from early stages of the disease. This study explores the possible relationships between these cognitive impairments in a group of 23 individuals with Parkinson's disease (PD) in comparison to a group of 18 healthy individuals. Compared with young individuals, normal aging is characterized by an increased association between executive function and episodic memory, especially with verbal material. We hypothesize that this association between verbal episodic memory and executive function may be weaker in PD as a consequence of the decline in these two cognitive abilities. To test this hypothesis, three categories of standardized tests were administered to both groups: (a) tests for executive function, (b) tests for visuospatial episodic memory, and (c) tests for verbal episodic memory. Performance outputs were analyzed using factor analysis, canonical regression, and structural equation modeling to obtain a holistic perspective of the linkage of these processes and to compare the differences between groups. In general, PD patients performed worse than controls in both executive function and episodic memory (with verbal and visuospatial material). Moreover, we found that relationships between executive function and visuospatial memory scores were high and quite similar in both groups. However, the relationship between verbal episodic memory and executive function was weaker in PD than in healthy individuals. These results suggest that a different brain mechanism could explain executive and verbal memory impairments in PD.

We examined the relationship between self-reported pre- and post-injury changes in executive dysfunction, apathy, disinhibition, and depression, and performance on neuropsychological tests of executive function, attention/processing speed, and memory in relation to mood levels and effort test performance in individuals in the early stages of recovery from mild to moderate traumatic brain injury (TBI).Participants were 71 noncombat military personnel who were in a semiacute stage of recovery (3 months post injury) from mild to moderate TBI. Pre- and post-TBI behaviors were assessed with the Frontal Systems Behavior Scale (FrSBe; GraceMalloy, 2001 ) and correlated with levels of depressive symptoms, effort test performance, and performance on objective measures of attention, executive function, and memory.Self-reported symptoms of executive dysfunction generally failed to predict performance on objective measures of executive function and memory, although they predicted poorer performance on measures of attention/processing speed. Instead, higher levels of depressive symptomatology best predicted poorer performance on measures of executive function and memory. However, the relationship between memory performance and TBI symptoms was no longer significant when effort performance was controlled.Our findings suggest that, among individuals in early recovery from mild to moderate TBI, self-reported depressive symptoms, rather than patients' cognitive complaints, are associated with objective executive function. However, self-reported cognitive complaints may be associated with objectively measured inattention and slow processing speed.

There is evidence that the e4 allele of the apolipoprotein E (APOE) gene is detrimental to cognitive function, but results from traumatic brain injury (TBI) populations are mixed. A possible explanation is that APOEe2 carriers have routinely been incorporated into APOEe4 and non-e4 groups, despite APOEe2 being proposed to have an ameliorative effect. Our primary aim was to investigate the influence of APOEe4 on cognitive impairment during early recovery following TBI, excluding the potential confound of APOEe2 possession. A secondary objective was to explore whether APOEe4 displays more pronounced effects in moderate to severe TBI and to consider the potential postinjury protective influence of the APOEe2 allele.Participants who recently sustained a TBI (posttraumatic amnesia5 minutes) were assessed on measures of information processing speed, executive function, and working memory upon remission of posttraumatic amnesia. APOE genotype was determined by buccal saliva DNA extraction (APOEe4 n = 37, APOEe3 n = 92, APOEe2 n = 13).Stepwise multiple regressions were performed to compare APOEe4 carriers to APOEe3 homozygotes, with injury severity, age, and estimated premorbid IQ included in the first step. This model was found to significantly predict performance on all tasks, accounting for 17.3-24.3% of the variance. When APOEe4 status was added for the second step, there were no significant changes on any tasks (additional variance1%). The effect of APOEe4 in moderate to severe TBI and the effect of APOEe2 were explored by analysis of covariance (ANCOVA), with no significant effects revealed.It is unlikely that APOE genotype influences cognitive function in the initial recovery period following TBI, regardless of injury severity. However, a more nuanced and long-term exploration of the effect of APOE genotype in the TBI population is warranted.

Procrastination, or the intentional delay of due tasks, is a widespread phenomenon in college settings. Because procrastination can negatively impact learning, achievement, academic self-efficacy, and quality of life, research has sought to understand the factors that produce and maintain this troublesome behavior. Procrastination is increasingly viewed as involving failures in self-regulation and volition, processes commonly regarded as executive functions. The present study was the first to investigate subcomponents of self-reported executive functioning associated with academic procrastination in a demographically diverse sample of college students aged 30 years and below (n = 212). We included each of nine aspects of executive functioning in multiple regression models that also included various demographic and medical/psychiatric characteristics, estimated IQ, depression, anxiety, neuroticism, and conscientiousness. The executive function domains of initiation, plan/organize, inhibit, self-monitor, working memory, task monitor, and organization of materials were significant predictors of academic procrastination in addition to increased age and lower conscientiousness. Results enhance understanding of the neuropsychological correlates of procrastination and may lead to practical suggestions or interventions to reduce its harmful effects on students' academic performance and well-being.

This study examined relationships between lobar volumes and performance on the Delis-Kaplan Executive Function System (D-KEFS) Sorting Test, a standardized measure of concept formation. There were 89 participants: 19 patients with probable Alzheimer's disease, 25 patients with frontotemporal dementia, 13 patients with semantic dementia, 12 patients with progressive nonfluent aphasia, 9 patients with probable progressive supranuclear palsy, 2 patients with possible progressive supranuclear palsy, and 9 healthy participants. We used BRAINS2 software to generate volumes of the right and left frontal, temporal, and parietal lobes. Multiple regression analysis indicated that, after controlling for Mini-Mental State Examination scores, intracranial volume, and demographic variables, only the left frontal lobe significantly predicted performance on the D-KEFS Sorting Test.

This study tested the ecological validity of four Delis-Kaplan Executive Function System (D-KEFS) tests by examining how well performance on D-KEFS measures predicted observed daily functioning in community-dwelling older adults. Older adults ages 65 to 92 years completed four D-KEFS tests requiring planning and cognitive fluency. The four combined D-KEFS measures accounted for approximately 26% of the variance in observed functional ability, when controlling for education and depression, thus supporting the ecological validity of the D-KEFS (Pearson r = .66). However, in a multiple regression analysis, the D-KEFS Trail Making Test-4 was the only measure of executive functioning that accounted for unique, independent variance in observed functional ability.

The Delis-Kaplan Executive Function System (D-KEFS; Delis, Kaplan,Kramer, 2001) represents the first set of executive tests co-normed on a large and representative national sample designed exclusively for the assessment of executive functions including flexibility of thinking, inhibition, problem solving, planning, impulse control, concept formation, abstract thinking, and creativity. The D-KEFS, composed of nine stand alone tests that can be individually or group administered, provides a standardized assessment of executive functions in children and adults between the ages of 8 and 89. Utilizing a "cognitive-process approach," the D-KEFS tests allow examiners to systematically generate and evaluate relevant clinical hypotheses on executive functioning of a given examinee by comparing and contrasting performance on multiple testing conditions and using contrast measure scores and error analyses. A review of the administration, scoring and interpretation, test construction, standardization, and technical adequacy indicate that the D-KEFS holds much promise not only as a clinical instrument, but also as a research tool for increasing knowledge of the frontal-lobe functions.

Despite a strong historical association between frontal lobe lesions and executive dysfunction, questions remain regarding the neuropsychological characterization of specific regions within the prefrontal cortex, as well as the utility of some executive function measures. The Delis-Kaplan Executive Function System (D-KEFS; Delis, Kaplan,Kramer, 2001) has gained popularity as a collection of executive function tests, but its sensitivity and specificity for detecting focal frontal lobe dysfunction remain uncertain. The current study investigated performances of patients with focal ventromedial prefrontal cortex (vmPFC, n = 13), dorsolateral prefrontal cortex (dlPFC, n = 14), and nonfrontal (NF, n = 18) lesions on the entire D-KEFS battery. We also obtained IQ data from conventional measures (the Wechsler Adult Intelligence Scale-Third Edition and Fourth Edition, WAIS-III/IV). On six D-KEFS indices, patients with dlPFC lesions performed lower than patients with vmPFC and NF lesions. On three other indices, the performances of the dlPFC group were lower than those of the NF group, but did not differ from those of the vmPFC group. However, none of these between-group differences were statistically significant after full-scale IQ and processing speed were controlled for, suggesting that the observed weaknesses in patients with dlPFC lesions were not specific to executive functions. Patients with vmPFC and NF lesions could not be differentiated based on their performances on any D-KEFS measures. While some D-KEFS measures show promise in differentiating patients with dlPFC lesions, the clinical advantage of using the D-KEFS over more traditional measures is not empirically compelling.

Neuropsychological tests are often used to evaluate executive function (EF) deficits in patients suffering traumatic brain injuries (TBIs). This study compared the sensitivity of three such tests--namely, the Delis-Kaplan Executive Function System Sorting Test (D-KEFS ST), the Wisconsin Card Sorting Test (WCST), and the Trail Making Test (TMT)--in differentiating between severe TBI patients and healthy controls. The differences between the two groups were significant for 5/5 variables evaluated through the D-KEFS ST, for 4/6 variables evaluated through the WCST, and for 2/2 variables evaluated through the TMT. Receiver operating characteristic analysis revealed that the variables "attempted sorts" in the D-KEFS ST and completion time in Part B of the TMT were the most powerful predictors of group assignment, with cutoff points of 9.5 sorts and 84.5 seconds, respectively. Our results highlight the possible value of the D-KEFS ST in the evaluation of postinjury EF deficits in TBI patients.

Use of neuropsychological tests to identify HIV-associated neurocognitive dysfunction must involve normative standards that are well suited to the population of interest. Norms should be based on a population of HIV-uninfected individuals as closely matched to the HIV-infected group as possible and must include examination of the potential effects of demographic factors on test performance. This is the first study to determine the normal range of scores on measures of psychomotor speed and executive function among a large group of ethnically and educationally diverse HIV-uninfected, high-risk women, as well as their HIV-infected counterparts. Participants (n = 1,653) were administered the Trail Making Test Parts A and B (Trails A and Trails B), the Symbol Digit Modalities Test (SDMT), and the Wide Range Achievement Test-3 (WRAT-3). Among HIV-uninfected women, race/ethnicity accounted for almost 5% of the variance in cognitive test performance. The proportions ofvariance in cognitive test performance accounted for by age (13.8%), years of school (4.1%), and WRAT-3 score (11.5%) were each significant, but did not completely account for the effect of race (3%). HIV-infected women obtained lower scores than HIV-uninfected women on time to complete Trails A and B, SDMT total correct, and SDMT incidental recall score, but after adjustment for age, years of education, racial/ethnic classification, and reading level, only the difference on SDMT total correct remained significant. Results highlight the need to adjust for demographic variables when diagnosing cognitive impairment in HIV-infected women. Advantages of demographically adjusted regression equations developed using data from HIV-uninfected women are discussed.

This study assessed executive functions in persons with mild cognitive impairment (MCI) using the Tower of London (TOL). A second objective was to study the impact of three types of problem selected according to the presence or absence of a "trigger." A trigger (T) is an incitation to the participant, at the first move, to move a ball to its final position according to the model. A positive trigger (T+) is helpful, while a negative trigger (T-) creates an obstruction. Some problems have no trigger (N). This study includes 81 participants with MCI. After follow-up, one year later, two subgroups were distinguished: (a) 51 (63%) participants did not convert or decline (stable MCI); (b) 30 (37%) participants showed significant decline or progressed to dementia (decliner MCI). Persons with MCI were compared to an older adult group matched with respect to sex, age, and education. For the successes, there was a significant group difference between the three types of problem. The post hoc analysis showed that T+ took significantly less time than N or T-. There were significantly more successes for T+ than N, and these two types of problem had more success than T-. For "total number of moves," there was no significant difference between the groups. In post hoc analysis, T- involved more moves than N or T+. In qualitative analysis, T- MCI decliners produced significantly more rule breakings than the stable MCI and controls. A dysfunction in self-monitoring is a characteristic feature of persons with MCI.

Multiple sclerosis (MS) is a disease of the central nervous system that causes cognitive impairment with a frequency of roughly 50%. While processing speed and memory defects are most commonly observed, a substantial number of patients also have deficiency in higher executive ability. Two tests, the Wisconsin Card Sorting Test (WCST) and the Sorting Test from the Delis-Kaplan Executive Function System (DKEFS), have been recommended for evaluation of neuropsychological impairment in MS. We investigated the validity of these tests in 111 MS patients and 46 age- and education-matched controls. MS patients performed more poorly on both measures, but only the DKEFS discriminated the groups after controlling for depression. Both tests were modestly or strongly correlated with MRI indices of brain atrophy or lesion burden and discriminated between employed and disabled patients. While both tests appear to have good validity in the MS population, the availability of alternative forms makes the DKEFS an attractive alternative to the WCST, as was suggested by a consensus panel.

Attention problems are ubiquitous in clinical practice, commonly found in many childhood learning and behavior disorders. Practitioners need cost- and time-effective methods for determining whether children have attention problems due to attention-deficit/hyperactivity disorder (ADHD) or numerous other conditions. This study examined the utility of a 15-minute ADHD screening battery designed to differentiate ADHD (including inattentive, IT, and combined, CT, subtypes), specific learning disability (SLD), and typical child samples. Results for the 368 children (age 6 to 12 years) revealed that the Trail Making Test-Part B (Time/Errors), Hale-Denckla Cancellation Test (Time/Correct), and Child Attention Profile (Inattention/Overactivity) teacher ratings discriminated between typical and ADHD groups (87% correct classification; sensitivity = .64; specificity = .92) and differentiated between IT, CT, and SLD groups (80% correct classification; IT sensitivity = .82, and specificity = .96; CT sensitivity = .84, and specificity = .82). Discriminant function and Bonferroni post hoc results revealed different neuropsychological and behavioral patterns among groups.

The purpose of this study was to examine the relationship between executive function and coping at one-year-post traumatic brain injury (TBI). TBI and matched control groups completed a coping questionnaire and a neuropsychological test series. In the TBI group, better executive performance was related to the use of problem focused coping (considered more adaptive). Conversely, lower executive performance was related to the use of emotion focused coping (considered more maladaptive). Planned hierarchical regression showed that executive function contributed significantly to the use of problem focused coping above and beyond pre-morbid intelligence and injury severity. Implications for cognitive rehabilitation are discussed.

We describe an interactive, computer-based test inspired by the Trail Making Test (TMT). In this new test, young (mean age = 20.4 years) and older participants (mean age = 74.9 years) used natural, pointing responses to order series of numbers, letters, or intermixed letters and numbers. This interactive test, which avoids several deficiencies of TMT, assesses participants' baseline speed for detecting and responding to individual items, captures the time for each response, and segregates erroneous responses from correct ones. The inter-response times with intermixed letters and numbers showed that participants did not always switch between the two different ordering tasks, but instead often recall letter-number pairs as single units. An additive factors analysis decomposed test times into functional components, including executive function, which took longer in older participants. With modest practice, both young and older participants sped up their ordering of intermixed numbers and letters, probably reflecting increased automaticity and reduced dependence upon executive function.

Relations among executive function, behavioral approach sensitivity, emotional decision making, and risk behaviors (alcohol use, drug use, and delinquent behavior) were examined in single female college students (N = 72). Hierarchical multiple regressions indicated a significant Approach Sensitivity x Working Memory interaction in which higher levels of alcohol use were associated with the combination of greater approach tendency and better working memory. This Approach Sensitivity x Working Memory interaction was also marginally significant for drug use and delinquency. Poor emotional decision making, as measured by a gambling task, was also associated with higher levels of alcohol use, but only for individuals low in inhibitory control. Findings point to the complexity of relations among aspects of self-regulation and personality and provide much needed data on neuropsychological correlates of risk behaviors in a nonclinical population.

This review considers the validity and suitability of neuropsychological and other tests of executive function for the detection of adult age differences in executive function. Executive function is typically assessed using tests which have been found to be sensitive to frontal lobe dysfunction because theory links executive function with the frontal lobes. However, any age-related decline in executive function is expected to be mild, or sub-clinical, compared to the deficits shown among those with frontal lesions. Therefore, in order to detect the type of mild executive dysfunction expected among older adults we need to employ tests sensitive enough to detect any age-related deficit, yet which are not too stressful or tiring for older adults to perform. This review discusses some commonly used neuropsychological tests of executive function as well as tests devised to assess theoretical aspects of executive function. Indications are given throughout as to which tests appear to be most suitable for detecting age differences in executive function.

Confabulation has traditionally been attributed to a combination of memory impairment and executive dysfunction, but recent models propose that confabulation can result from executive dysfunction alone. One hundred and ten patients with diverse neurologic and psychiatric diagnoses were subdivided into high-, low-, and non-confabulator groups based upon the ratio of confabulations to total responses produced during story recall. Consistent with the combined deficit model, high-confabulators performed significantly worse than the low- and non-confabulators on measures of memory and measures of executive function that assess sustained attention, mental tracking, and set-shifting ability. However, there were no differences between groups on measures of problem-solving, concept formation, and verbal fluency, suggesting a dissociation in executive functions that contribute to confabulation.

Persons with amnestic mild cognitive impairment (MCI) show deficits on executive function measures, although the neuroanatomic basis of executive function in MCI is unknown. We investigated cognitive correlates of 3-tesla proton magnetic resonance spectroscopy (MRS) of the posterior cingulate gyrus in 26 MCI patients. Posterior cingulate ratio of myo-inositol to creatine (mI/Cr) was negatively correlated (-.51) with spontaneous clock drawing. This relationship was not attenuated after accounting for age, overall cognitive function, or memory performance. This finding suggests a role for the posterior cingulate in executive function in MCI. Proton MRS may offer a means to track neurometabolic changes associated with cognitive impairment in MCI.

The study of executive function within a developmental framework has proven integral to the advancement of knowledge concerning the acquisition and decline of higher skill processes. Still in its early stages, there exists a discontinuity in the literature between the exploration of executive capacity in young children and the elderly. Research of age-related differences utilising a lifespan approach has been restricted by the lack of assessment tools for the measurement of executive skills that are applicable across all age levels. This paper addresses these issues using the computer-based Cambridge Neuropsychological Test Automated Battery (CANTAB) to identify periods of development in executive capacities using a normative sample of 194 participants ranging in age from 8 to 64 years. Findings of executive function in children as young as 8 years of age were extended, with functional gains found in the efficiency of working memory capacity, planning and problem-solving abilities, between the ages of 15 and 19 years and again at 20-29 years of age. Cognitive flexibility was assessed at adult-levels in even the youngest children. Declines in performance on all tasks were revealed for the 50-64 year old sample, providing support for the vulnerability of executive skills to normal aging.

This study investigated adult age differences in, and predictors of, the performance of a test of executive function, the Self-Ordered Pointing Task (SOPT; Petrides & Milner, 1982). Performance on the SOPT is thought to rely on high level working memory processes, therefore, measures reflecting the common operationalization of working memory, along with measures of executive function and speed of information processing, were investigated as predictors of SOPT performance. Younger (aged 17-48 years) and older (aged 65-88 years) adults completed a 16-item, 3-trial, modified version of Shimamura and Jurica's (1994) version of the SOPT, and tests assessing working memory, executive function and speed. Results showed that younger adults made fewer errors on the SOPT. There was no age difference in the frequency of use of a clustering strategy. Contrary to expectations, working memory was not a good predictor of individual or age differences in SOPT performance. Instead, speed of processing, and to a lesser extent, measures of perseverations, made larger unique and overlapping contributions to the variance. The SOPT and its association, or dissociation, with other measures of working memory may be useful for research into the nature of working memory and executive function and the theoretical links between them.

Interactive effects of past noninjection drug abuse/dependence and HIV disease status upon measures of executive function were assessed in a group of 294 homosexual men. Participants were stratified according to HIV status and substance use diagnoses, thereby yielding a 4 (seronegative, asymptomatic seropositive, symptomatic seropositive, and AIDS defining illness) x 2 (never abused drugs, previous substance use disorder) design. Significant main effects of HIV status were found on the Wisconsin Card Sorting Test, Ruff Figural Fluency Test, Trail Making Test B, and total number of impaired performances. Analyses revealed that men with AIDS defining illness performed worse than the other three groups. Drug use history had no significant effect upon neurobehavioral function, and effect sizes for drug abuse history were small. The data suggest that prior drug use yields little if any residual cognitive impairment in HIV infection.

Neuropsychological performance in 151 patients with schizophrenia was examined using cluster analysis to identify neurocognitive subtypes. Hierarchical and iterative partitioning methods identified four clusters using an extended neuropsychological battery. Consistent with previous findings two extreme clusters were characterized by near normative performance and profound global dysfunction, respectively. The two remaining neurocognitive clusters displayed moderate-severe dysfunction and were differentiated by unique patterns of abstraction and flexibility, attention, spatial memory, and sensory-perception. Analysis of variance revealed an interaction between global memory and executive function for clusters III and IV. Although limited cluster differences were found relative to clinical and historical data, the distribution of previously defined clinical subtypes was uneven among neurocognitive clusters. Paranoid patients were significantly more likely to be classified into cluster II and disproportionately absent from clusters I and IV. Patients with negative and disorganized clinical subtypes comprised a disproportionate component of clusters I and IV but were less likely to be classified in cluster II. This suggests greater correspondence than previously postulated between systems responsible for clinical symptomatology and those moderating neurocognitive dysfunction.

In order to distinguish impairment in set-shifting in Parkinson's disease (PD) from inability to inhibit distraction by stimuli that compete for attention, 18 nondemented patients with idiopathic PD and 13 normal controls equated for age and education, were administered the Odd-Man Out (OMO) test and the Stroop Color-Word Test. PD patients were significantly impaired on the OMO test but showed no evidence of interference during the Stroop test. Analysis of error patterns during the OMO test indicated that the requirement to repeatedly switch rules, rather than the requirement to maintain steady responding between rule switches, was responsible for impaired OMO performance. It is concluded that the OMO test is fundamentally a test of set shifting, rather than a test of set maintenance in PD. In addition, analysis of a larger sample of PD patients revealed a significant positive relationship between number and severity of extrapyramidal signs and error production on the OMO, and between the latter and global mental function. These relationships were independent of each other, suggesting that impairment in set-shifting function in PD may arise from pathology of the fronto-striatal system independently of changes in cognitive ability.

Although executive functioning (EF) correlates with execution of instrumental activities of daily living (IADLs), tests of EF have been criticized for having poor ecological validity. Attempts have been made to develop new tests that approximate naturalistic daily tasks. However, the incremental utility of such tests has not been convincingly demonstrated. The Night Out Task (NOT) is a novel measure designed to increase ecological validity. This study examined whether the NOT correlates with traditional lab- and home-based measures of EF and IADLs, and whether it outperforms traditional measures of EF in predicting IADLs.Participants (50 adults aged 60 to 95) completed (1) the Delis Kaplan Executive Function System (D-KEFS) and IADLs in the laboratory, and (2) ecological momentary assessment of EF and daily IADL tasks at home across three weeks (using the Daily Assessment of Independent Living and Executive Skills protocol; DAILIES).The NOT correlated with a lab-based measure of EF beyond covariates, and lab-based IADLs beyond covariates and beyond the D-KEFS. However, it was unrelated to at-home variables beyond covariates. In contrast, the D-KEFS was a significant predictor of at-home IADLs, and this association was mediated by at-home EF performance.This study provides a preliminary validation of the NOT as a correlate of office-based performances in a primarily college educated white sample. Despite its high face validity, the NOT does not appear to sufficiently tap EF processes needed for home-based IADLs as measured by the DAILIES, although small sample size limits the interpretability of this negative finding.

While event-based prospective memory refers to enacting intending action in response to a specific event or cue ("e.g., When I tell you there are 10 minutes left, please give me this stopwatch"), time-based prospective memory refers to enacting intending action in relation to a specific time ("In 10 minutes time, please ask me for a pencil"). Relative to event-based prospective memory, little is known about time-based prospective memory in Korsakoff's syndrome (KS).We used behavioral tasks to investigate event- and time-based prospective memory as well as episodic memory and executive function in patients with KS and control participants.Analysis demonstrated lower event- and time-based prospective memory in patients with KS than in control participants. Interestingly, we found lower time-based than event-based prospective memory in patients with KS. Further, significant correlations were observed between prospective memory and episodic memory and executive function in the patients.Prospective memory is important for everyday life tasks, and failures of prospective memory can endanger patients' safety. One clinical implication of our findings is the importance of including an evaluation of prospective memory in cognitive evaluation of KS.

Conflicting evidence has arisen from the few correlational studies that have examined the relationship between the ability to decode social emotional cues through the eyes and executive functions in individuals with prefrontal cortex damage. The objective of the current study was (1) to investigate the impact of both focal prefrontal and parietal cortex damage on both of these domains; (2) to examine whether impaired ability to decode social emotion cues through the eyes was predicted by executive function deficits and; (3) to explore the neural correlates of both of these components.Thirty individuals with prefrontal cortex damage, 15 individuals with parietal cortex damage and 30 matched healthy comparison subjects were subjected to a battery of executive tasks assessing inhibition, flexibility, and planning processes and the Reading the Mind in the Eyes Task (RMET) assessing ability to decode social emotion cues through the eyes.Compared to both comparison groups, individuals with prefrontal cortex damage were impaired in performing RMET and almost all executive tasks. Regression analysis showed that for individuals with prefrontal cortex damage, performance on the Stroop and Hayling tasks predicted scores on the RMET, while for the healthy comparison group, only the verbal fluency performance predicted scores on the RMET. The Voxel lesions-symptom mapping technique showed that both components rely partly on the same neural substrates, reflecting beyond the neural network of RMET per se that of the cognitive processes elicited by this multi-determinant task.These findings suggest that the ability to read mental states of mind depends on the inhibition and flexibility executive mechanisms.

The Delis-Kaplan Executive Function System (D-KEFS) Trail Making Test (TMT) is a commonly used measure of processing speed and executive functioning that may also be useful as an embedded performance validity test (PVT). We evaluated the utility of several multi-condition indices on the D-KEFS TMT in three independent samples to determine an optimal multi-condition index and cutoff on the D-KEFS TMT.Classification accuracy statistics for multiple multi-condition indices on the D-KEFS TMT were evaluated in three independent samples, including a sample with history of mild traumatic brain injury (TBI; n = 267) classified into psychometrically defined performance-valid and performance-invalid subgroups, the D-KEFS national normative sample (n = 1713), and a sample of middle- and older-aged adults diagnosed with mild cognitive impairment (MCI; n = 70).The D-KEFS TMT Conditions 1-5 summation index maximized sensitivity at .31 while maintaining adequate specificity at ≥.9. This index also had acceptable classification accuracy in both the D-KEFS national normative and MCI cross-validation samples, with the exception of the oldest subgroup of the national norming sample (i.e., individuals' ages 80-89), in which the observed failure rates for all multi-condition indices tested were greater than 10%.Our study provides support for the use the D-KEFS TMT Conditions 1-5 summation index as an embedded PVT among individuals younger than 80 years-old and from a range of conditions spanning from cognitively normal to mildly impaired; however, further validation is necessary.

Few studies have considered health-related quality of life (HRQOL) as a primary outcome measure in adult survivors of primary brain tumor (PBT), and fewer still have studied the cognitive factors that may influence it. Research suggests that executive functions (EFs) are associated with HRQOL, but there is scant evidence to support this. The present study was conducted to (1) extend prior findings about HRQOL limitations in a sample of stable, long-term adult survivors of PBT, (2) investigate the associations between objective/reported EFs and HRQOL, and (3) identify the EFs that contribute most to HRQOL.We recruited 40 survivors of PBT (2 years post-treatment) and 40 matched healthy controls. Participants completed an objective EF assessment (inhibition, working memory, shifting, and rule detection) and two self-report questionnaires probing EFs (Behavior Rating Inventory of Executive Function-Adult) and HRQOL (Medical Outcomes Study Short-Form 36). Participants' relatives completed observer-rated versions of these questionnaires.Patients' objective EF performances were relatively intact. However, patients and caregivers reported significantly more problems than healthy controls and their relatives, for both EFs and HRQOL. There were only negligible links between objective EFs and HRQOL, whereas numerous associations were found between reported EFs and HRQOL components. ANCOVA models revealed that specific reported EF processes contributed to both the physical and mental components of HRQOL, regardless of group.From a clinical point of view, this study demonstrates that even several years after end of treatment, adult PBT survivors experience substantial problems across different HRQOL domains. HRQOL assessment should therefore be part of the long-term follow-up of PBT survivors, and clinicians should consider EF limitations when designing appropriate survivorship care plans. These findings indicate that cognitive interventions targeting EFs could improve HRQOL.

Emerging evidence highlights intraindividual variability (IIV) during executive function (EF) tasks as a reliable endophenotype of Attention Deficit/Hyperactivity Disorder (ADHD) and as contributing to motor dysregulation and hyperactive-impulsive behaviors. This study examined the relationship between EF and motor control in children with and without ADHD.Ninety-seven children (6-13 years) completed standardized and experimental tasks of executive and motor control. Primary caregivers completed a semi-structured interview, and behavioral rating forms for ADHD symptoms and EF.Children with ADHD demonstrated lower performance on motor dexterity and sequencing tasks, and greater IIV during EF tasks with lower cognitive demand. IIV accounted for ADHD symptoms of hyperactivity, beyond age and motor dexterity. IIV from EF measures with lower cognitive demand was also sensitive to ADHD symptoms.IIV metrics may tap into the motor regulation challenges associated with ADHD, as well as attentional lapsing at lower levels of cognitive demand.

To synthesize quantitatively the mild cognitive impairment (MCI) literature with respect to the relationship between cognitive reserve and neuropsychological and functional outcomes.Participants with a diagnosis of MCI (total n = 7,871; 53% female) were included in this random-effects meta-analysis. Neuropsychological measures were combined into composite scores (e.g., overall cognitive functioning, screening measures, memory, language, visuospatial, attention/processing speed/working memory, executive functioning, and motor functioning). Measures assessing real-world abilities were combined into an activities of daily living (ADL) composite.Nearly all neuropsychological composite values were significantly correlated with education, with effect sizes ranging from small to moderate. The effect between overall neuropsychological functioning and occupation was weak and varied by cognitive domain. For cognitively stimulating leisure activity, only overall neuropsychological functioning demonstrated a significant relationship, with a weak effect size (r = .16). In contrast, ADLs were most strongly associated with leisure experience (r = .27), with a negligible relationship with education (r = 0.08) and occupation (r = 0.09).Of the cognitive reserve proxies examined in this study, participation in leisure activity had the largest magnitude of effect size with ADL functioning. This was in stark contrast to the negligible relationship found for education and occupation. Although education has been widely considered the most important cognitive reserve proxy with respect to cognition, this work questions whether other lifestyle factors may play a more important role in preserving real world functioning.