The Delis–Kaplan Executive Function System Sorting Test as an evaluative tool for executive functions after severe traumatic brain injury: A comparative study

Testing associations between assessments of cognitive flexibility and eating disorder symptoms in adolescent bulimia nervosa

OBJECTIVE

Cognitive rigidity, or difficulty adapting to changing demands, is commonly observed in anorexia nervosa. Less is known, however, about cognitive flexibility (CF) in bulimia nervosa (BN) and, particularly, adolescence. Clarifying this relation and best assessment practices may guide informed clinical decision-making. The current study compared how two measures of CF (i.e., Wisconsin Card Sort Task [WCST] and Trail Making Task [TMT]) relate to BN symptoms among adolescents.

METHODS

Data from a subsample (n = 78) of adolescents with BN were analyzed. Linear and hurdle regressions were used to compare the effects of WCST perseverative errors and TMT performance on Eating Disorder Examination Global Scores, objective binge episodes, and self-induced vomiting episodes (SVEs) at baseline and end-of-treatment (EOT).

RESULTS

Neither CF measure associated with baseline BN symptoms. TMT performance positively associated with the likelihood of engaging in SVEs at EOT (𝛽 = 0.47, p = 0.01, 95% confidence interval [CI] = [0.11-0.84]) and, among adolescents who endorsed ≥1 SVE at EOT, WCST perseverative errors (𝛽 = 0.05, p = 0.005, 95% CI = [0.01-0.08]) positively associated with SVE frequency at EOT.

DISCUSSION

The overall lack of associations between CF and outcomes suggests that cognitive rigidity may not be as relevant to the clinical profile of adolescent BN as for anorexia nervosa. In the few significant associations that emerged, the WCST and TMT uniquely predicted the severity of vomiting at EOT in this sample. Given the lack of CF deficits, future work should aim to test the role of other executive functions (e.g., impulsivity), in addition to CF, to determine which deficits are present in adolescent BN and may predict outcomes.

PUBLIC SIGNIFICANCE

Patients with eating disorders often have difficulties thinking flexibly, which may interfere with their recovery. We tested two ways of measuring flexible thinking in adolescents with BN. Overall, flexible thinking was not associated with symptom-level outcomes. However, less flexible thinking at the start of treatment predicted self-induced vomiting at EOT. If findings are replicable, then assessing and addressing flexible thinking could improve outcomes for adolescents with BN.

Examining the validity of the Delis-Kaplan Executive Function System (D-KEFS) in traumatic brain injury

This study examines the validity of the Delis-Kaplan Executive Function System (D-KEFS) in a traumatic brain injury (TBI) population compared to participants with orthopaedic injuries and normative controls. The utility of the D-KEFS was examined using a between groups design. One hundred patients with mild uncomplicated to severe TBI were recruited from a consecutive cohort of patients admitted as inpatients to a UK Major Trauma Centre and compared to 823 participants from the D-KEFS normative sample and 26 participants with orthopaedic injuries. Data were filtered for performance validity. Sample discrimination was calculated from D-KEFS subtest scores and derived index scores. Sensitivity to TBI severity was established. The TBI participants performed significantly lower on the D-KEFS Trail Making Test, Colour Word Interference, Colour Word Switching, Letter Fluency and Verbal Fluency Category Switching Total Words Correct. The D-KEFS index scores discriminated between TBI, orthopaedic and normative participants with large and moderate effect sizes, respectively. The D-KEFS demonstrated a dose-response relationship with TBI severity. These effects were robust to differences in premorbid intellectual functioning; however, D-KEFS performance was sensitive to performance on tests of mental processing speed. The use of a D-KEFS index score provides a robust and reliable discrimination of TBI patients from healthy control participants. This discrimination is not accounted for by premorbid intellect or the non-specific effects of trauma. The clinical and conceptual implications of these findings are considered.

Neuropsychological Assessment in Patients with Traumatic Brain Injury: A Comprehensive Review with Clinical Recommendations

Traumatic brain injury is damage to the brain occurring after birth, often resulting in the deterioration of cognitive, behavioural, and emotional functions. Neuropsychological evaluation can assist clinicians to better assess the patient's clinical condition, reach differential diagnoses, and develop interventional strategies. However, considering the multiple rating scales available, it is not easy to establish which tool is most suitable for the different brain injury conditions. The aim of this review is to investigate and describe the most used neurocognitive assessment tools in patients with traumatic brain injury to provide clinicians with clear indications on their use in clinical practice. Indeed, during the acute phase, after the head trauma, alertness and wakefulness of the patients affected by a disorder of consciousness can be assessed using different scales, such as the Coma Recovery Scale-Revised. In both postacute and chronic phases after traumatic brain injury, general cognitive assessment tools (such as the Mini Mental State Examination) or more specific cognitive tests (e.g., Wisconsin Card Sorting Test and Trail Making Test) could be administered according to the patient's functional status. In this way, clinicians may be aware of the patient's neuropsychological and cognitive level, so they can guarantee a personalized and tailored rehabilitation approach in this frail patient population.

Sensitivity of conventional cognitive tests in multiple sclerosis: Application of item response theory

BACKGROUND

Cognitive impairment (CI) is common in Multiple Sclerosis (MS), and its prevalence rate ranges between 22% and 70%. Because CI significantly impacts vocational status, caregiver burden, and quality of life, an accurate neuropsychological assessment is required. Three widely used and validated batteries for MS-associated CI are the Brief Repeatable Neuropsychological Battery (BRN-B), the Minimal Assessment of Cognitive Function (MACFIMS), and the Brief International Cognitive Assessment (BICAMS). Although similar, these batteries differ in time-consuming and in specific tests employed. This study aims to assess the sensitivity of cognitive tests included in these batteries through an Item Response Theory approach.

METHODS

Ninety-seven patients with MS and 91 demographically matched controls (HC) were consecutively assessed using the three neuropsychological batteries (i.e., BRN-B, MACFIMS, and BICAMS). Continuous Response Model (CRM) was used to identify the cognitive test(s) that best discriminate patients with MS from HC. Receiver Operating Characteristic (ROC) curve analysis was used to determine the accuracy of the CRM results.

RESULTS

Cognitive tests loaded on two different latent variables: the 'higher-order executive functioning,' consisting of tests assessing concept formation, problem-solving, and inhibitory control, and the 'memory and information processing speed,' comprising tests assessing long-term, working memory, and information processing speed. The Delis Kaplan Executive Functioning System-Sorting Test and the Stroop Test were the most sensitive tests in differentiating cognitive functioning between MS and HC.

CONCLUSIONS

This study confirms the importance of including a more extensive executive assessment in MS clinical practice since higher-order executive functions (e.g., abstraction and inhibitory control) significantly impact patients' quality of life and functional autonomy. Clinical implications of careful dissection of executive functioning in MS neuropsychological assessment are discussed.

Evaluation of post-traumatic stress disorder (PTSD) and related comorbidities in clinical studies

Patients with traumatic brain injury (TBI) of varying severities are experiencing adverse outcomes during and after rehabilitation. Besides depression and anxiety, post-traumatic stress disorder (PTSD) is highly encountered in civilian and military populations. As more prospective and retrospective studies - focused on evaluating new or old psychological therapies in inpatient, outpatient, or controlled environments, targeting patients with PTSD with or without a history of TBI - are carried out, researchers are employing various scales to measure PTSD as well as other psychiatric diagnoses or cognitive impairments that might appear following TBI. We aimed to explore the literature published between January 2010 and October 2021 by querying three databases. Our preliminary results showed that several scales - such as the Clinician-Administered PTSD Scale (CAPS), the Posttraumatic Stress Disorder Checklist Military Version (PCL-M) as well as Specific Version (PCL-S), and Civilian Version (PCL-C) - have been frequently used for PTSD diagnosis and symptom severity. However, heterogeneity in the scales used when assessing and evaluating additional psychiatric comorbidities and cognitive impairments are due to the study aim and therapeutic approaches. Therefore, conducting an intervention focusing on post-TBI PTSD patients requires increased attention to patients' medical history in capturing multiple cognitive impairments and affected neuropsychological processes when designing the study and including validated instruments for measuring primary and secondary neuropsychological outcomes.

Life is about "constant evolution": the experience of living with an acquired brain injury in individuals who report higher or lower posttraumatic growth

OBJECTIVE

To explore the experience of living with an Acquired Brain Injury (ABI) in individuals who report higher or lower posttraumatic growth (PTG).

METHOD

A multi-method design was employed. Participant scores on the Posttraumatic Growth Inventory (PTGI) were used to identify groups for qualitative comparative analysis. Individual semi-structured interviews were conducted with fourteen individuals with ABI. Data were analysed thematically.

RESULTS

Four themes emerged. The first two themes: "In my mind I was fine" surviving in aftermath of acquiring a brain injury and The everyday as "derailing" capture the transition process from an initial rehabilitation state characterised by neuropsychological and avoidance coping, towards active rebuilding for PTG. Internal building blocks for PTG and Growing in the social world: "you need to have that social connection" elaborate on the internal (e.g., acceptance, integration of the pre and post-injury self) and external (e.g., social relationships) factors seen to facilitate or obstruct PTG.

CONCLUSIONS

Under certain conditions, individuals living with ABI may construe positive growth from their experiences. Practitioners can support PTG development by providing individual and family-based supports aimed at increasing acceptance, the integration of self, and social connection throughout all stages of ABI rehabilitation.IMPLICATIONS FOR REHABILITATIONInternal factors such as having a flexible and positive mindset and external factors such as one's social environment can affect how individuals living with an ABI construe positive growth.Individuals with ABI and their families require access to individualised longitudinal support for neuropsychological and social challenges that can result in increased distress and obstruct the development of PTG.Efforts to facilitate acceptance and support the integration of the pre and post-injury self through recognition of continuity of self and processing of new schematic beliefs can benefit PTG development.Rehabilitation providers should support individuals with ABI to develop or maintain a positive social identity within new or existing social groups.

Assessment of Executive Function in Patients with Traumatic Brain Injury with the Wisconsin Card-Sorting Test

This review aimed at providing a brief and comprehensive summary of recent research regarding the use of the Wisconsin Card-Sorting Test (WCST) to assess executive function in patients with traumatic brain injury (TBI). A bibliographical search, performed in PubMed, Web of Science, Scopus, Cochrane Library, and PsycInfo, targeted publications from 2010 to 2020, in English or Spanish. Information regarding the studies’ designs, sample features and use of the WCST scores was recorded. An initial search eliciting 387 citations was reduced to 47 relevant papers. The highest proportion of publications came from the United States of America (34.0%) and included adult patients (95.7%). Observational designs were the most frequent (85.1%), the highest proportion being cross-sectional or case series studies. The average time after the occurrence of the TBI ranged from 4 to 62 years in single case studies, and from 6 weeks up to 23.5 years in the studies with more than one patient. Four studies compared groups of patients with TBI according to the severity (mild, moderate and/or severe), and in two cases, the studies compared TBI patients with healthy controls. Randomized control trials were seven in total. The noncomputerized WCST version including 128 cards was the most frequently used (78.7%). Characterization of the clinical profile of participants was the most frequent purpose (34.0%). The WCST is a common measure of executive function in patients with TBI. Although shorter and/or computerized versions are available, the original WCST with 128 cards is still used most often. The WCST is a useful tool for research and clinical purposes, yet a common practice is to report only one or a few of the possible scores, which prevents further valid comparisons across studies. Results might be useful to professionals in the clinical and research fields to guide them in assessment planning and proper interpretation of the WCST scores.

Executive function moderates naltrexone effects on methamphetamine-induced craving and subjective responses

Background: Emerging evidence suggests that opioid receptor antagonists, such as naltrexone, are effective pharmacotherapies for alcohol, opioid, and possibly stimulant use disorders. It is posited that naltrexone exerts its effects, in part, by increasing functional connectivity between neural reward circuitry and frontal systems implicated in executive function. Yet no studies had examined whether executive function moderates these effects. Objectives: This study examined whether a composite measure of executive function (EF) moderates the effect of naltrexone on craving for methamphetamine and subjective responses following infusion of the drug. Methods: Individuals with methamphetamine use disorder (N = 30; 27% female) completed baseline neurocognitive assessments of premorbid and executive function, and an executive function factor was computed. Participants then underwent a randomized, double-blind, cross-over study of titration with naltrexone and placebo. Participants then received a 30-mg intravenous methamphetamine infusion and completed subjective response questionnaires at 8 times in the 120 minutes post-infusion. Results: Multilevel mixed models indicated a significant EF × medication interaction, reflecting greater effects of naltrexone to decrease "desire to access the drug", "want more of the drug", "crave the drug", "feel drug effects" and "feel high" in participants with low EF compared to those with high EF (Bs = .36-1.29, SEs = .14-.17, ps<0.01). These effects remained significant after controlling for premorbid cognitive functioning, baseline responses to methamphetamine, severity of methamphetamine use, and methamphetamine-related functional problems. Conclusion: Naltrexone may be especially effective in methamphetamine-dependent individuals with low EF. Neuropsychological assessments may also provide predictive clinical utility not captured by traditional measures of substance use severity.

The Other Side of the Bell Curve: Multivariate Base Rates of High Scores on the Delis-Kaplan Executive Function System

OBJECTIVE

Previous researchers have examined the frequency at which healthy participants obtain one or more low scores on neuropsychological test batteries, proposing five psychometric principles of multivariate base rates: (a) low scores are common, with their frequency contingent on (b) the low score cutoff used, (c) the number of tests administered/interpreted, and (d) the demographic characteristics and (e) intelligence of participants. The current study explored whether these principles applied to high scores as well, using the Delis-Kaplan Executive Function System (D-KEFS).

METHOD

Multivariate base rates of high scores (≥75th, ≥84th, ≥91st, ≥95th, and ≥98th percentiles) were derived for a three-test, four-test, and full D-KEFS battery, using the adult portion of the normative sample (aged 16-89 years; N = 1050) stratified by education and intelligence. The full D-KEFS battery provides 16 total achievement scores (primary indicators of executive function).

RESULTS

High scores occurred commonly for all batteries. For the three-test battery, 24.1% and 12.4% had 1 or more scores ≥95th percentile and ≥98th percentile, respectively. High scores occurred more often for longer batteries: 61.6%, 72.9%, and 87.8% obtained 1 or more scores ≥84th percentile for the three-test, four-test, and full batteries, respectively. The frequency of high scores increased with more education and higher intelligence.

CONCLUSIONS

The principles of multivariate base rates also applied to high D-KEFS scores: high scores were common and contingent on the cutoff used, number of tests administered/interpreted, and education/intelligence of examinees. Base rates of high scores may help clinicians identify true cognitive strengths and detect cognitive deficits in high functioning people.

Trail Making Test, Stroop, and Verbal Fluency: Regression-Based Norms for the Icelandic Population

Objective

The aim of this study was to construct regression-based norms for 3 executive-function tests: the Trail Making Test, Stroop, and Verbal Fluency.

Method

A sample of 1,034 healthy Icelandic adults (18–64 years) was used to calculate predicted scores for test measures from all 3 tests, controlled for the effects of age, gender, and education, as well as the interaction between these variables.

Results

The 3 demographic variables showed significant effects on most test measures and were included in the final equation for estimating predicted scores. An older age and less education predicted worse cognitive performances in most cases, and women tended to outperform men.

Conclusion

These results highlight the importance of adjusting for age, gender, and educational level when constructing normative data. Controlling for age alone may be insufficient or misleading in clinical-practice settings. A simple, user-friendly program for predicting executive-function test scores is provided.

Patients with Lesions to Left Prefrontal Cortex (BA 9 and BA 10) Have Less Entrenched Beliefs and Are More Skeptical Reasoners

The effect of prior beliefs on reasoning and decision-making is a robust, poorly understood phenomenon, exhibiting considerable individual variation. Neuroimaging studies widely show the involvement of the left pFC in reasoning involving beliefs. However, little patient data exist to speak to the necessity and role of the left pFC in belief-based inference. To address this shortcoming, we tested 102 patients with unilateral focal penetrating traumatic brain injuries and 49 matched controls. Participants provided plausibility ratings (plausible/implausible) to simple inductive arguments and (separately) strength of believability ratings of the conclusion to those same arguments. A voxel-based lesion symptom mapping analysis identified 10 patients, all with lesions to the left pFC (BA 9 and BA 10) as rating significantly fewer arguments with highly believable conclusions as "plausible," compared with all other patients. Subsequent analyses, incorporating the right hemisphere homologue of these patients (n = 12) and normal controls (n = 24), revealed patients with lesions to left pFC found fewer arguments plausible in the high believable than either of these groups, and there was no difference in the behavioral scores of the right pFC patients and normal controls. Further analysis, utilizing the belief ratings as the dependent measure, revealed a Group × Belief Rating interaction, with left pFC patients having less intense beliefs about the conclusions of moderately believable and highly believable arguments. We interpreted these results to indicate that lesions to left pFC (BA 9, BA 10) increase incredulity and make these patients more skeptical reasoners. The former can partially, but not fully, explain the latter. The other relevant factor may be that unilateral left pFC lesions disrupt hemispheric equilibrium and allow for an increased inhibitory role of the right pFC. We speculate that individual differences in belief bias in reasoning in the normal population may be a function of individual differences in the left and right pFC interactional dynamics.

D-KEFS ST Failure Identifies Multiple Sclerosis Patients With Worse Objective and Self-Perceived Physical and Cognitive Disability

Background and Objectives: The Brief Repeatable Battery of Neuropsychological Test (BRB-NT) does not explore the executive functions. We combined BRB-NT and Delis-Kaplan Executive Function System Sorting Test (D-KEFS ST) to obtain a more comprehensive evaluation of cognitive impairment in Multiple Sclerosis (MS) patients.

Methods: 137 Relapsing Remitting MS (RRMS) patients underwent a detailed neuropsychological assessment including BRB-NT, D-KEFS ST and self-administrated questionnaires, namely the Multiple Sclerosis Neuropsychological Questionnaire (MSNQ), the Fatigue Severity Scale (FSS) and the Beck Depression Inventory-Second Edition (BDI-II).

Results: Fifty-four patients (39.4%) had normal scores in each item of both batteries (cognitive normal), while 64 patients (46.7%) failed in at least one test of BRB-NT but not of D-KEFS ST (BRB-NT impaired) and 18 (13.1%) failed in at least one test of both batteries (BRB-NT+D-KEFS ST impaired). Only one patient (0.7%) failed in D-KEFS ST, but not in BRB-NT and was excluded from further analysis. BRB-NT+D-KEFS ST impaired patients had a significant higher mean disease duration and median EDSS score (15.5 ± 13.6 years and 3.5, respectively) compared to those with only BRB-NT impaired (7.9 ± 9.2, p < 0.01 and 2.5, p < 0.05) and with cognitive normal patients (6.7 ± 9.4, p < 0.005 and 2.0, p < 0.01). SDMT was more frequently impaired in BRB-NT+D-KEFS ST impaired patients (77.8%) compared to only BRB-NT impaired ones (20.0%, p < 0.001). The failure in D-KEFS ST was associated with the number of failed BRB-NT items (OR 1.46, IC95% 1.07–1.99, p < 0.05) and with pathological SDMT z-value (OR 10.56, IC95% 2.50–44.66, p < 0.005). Compared to BRB-NT impaired patients and the cognitive normal ones, BRB-NT+D-KEFS ST impaired patients had significant higher MSNQ (p < 0.01) and BDI-II (p < 0.05) values.

Conclusion: D-KEFS ST did not increase the number of cognitively impaired MS patients identified by BRB-NT, but provided a more comprehensive evaluation of cognitive decline. D-KEFS ST identified a subgroup of patients with increased self-perception of cognitive decline, depression and higher physical disability.

Traumatic brain injury and frontal lobe plasticity

Over 1.4 million people in the United States experience traumatic brain injury (TBI) each year and approximately 52,000 people die annually due to complications related to TBI. Traditionally, TBI has been viewed as a static injury with significant consequences for frontal lobe functioning that plateaus after some window of recovery, remaining relatively stable thereafter. However, over the past decade there has been growing consensus that the consequences of TBI are dynamic, with unique characteristics expressed at the individual level and over the life span. This chapter first discusses the pathophysiology of TBI in order to understand its dynamic process and then describes the behavioral changes that are the result of injury with focus on frontal lobe functions. It integrates a historical perspective on structural and functional brain-imaging approaches used to understand how TBI impacts the frontal lobes, as well as more recent approaches to examine large-scale network changes after TBI. The factors most useful for outcome prediction are surveyed, along with how the theoretical frameworks used to predict recovery have developed over time. In this chapter, the authors argue for the need to understand outcome after TBI as a dynamic process with individual trajectories, taking a network theory perspective to understand the consequences of disrupting frontal systems in TBI. Within this framework, understanding frontal lobe dysfunction within a larger coordinated neural network to study TBI may provide a novel perspective in outcome prediction and in developing individualized treatments.

Nih toolbox premorbid ability adjustments: Application in a traumatic brain injury sample

PURPOSE/OBJECTIVE

Metrics to estimate premorbid cognitive ability, such as word reading tests, are important for clinical determination of cognitive changes following brain injury. In the present study, reading adjusted scores for the National Institutes of Health Toolbox Cognition Battery (NIHTB-CB) fluid tests were developed and validated with a sample of individuals with traumatic brain injury (TBI), to evaluate the clinical utility of reading-adjusted scores. Research Method/Design: The development sample included 843 adult participants, ages 20-85, from the NIHTB-CB standardization sample. A sample of 158 participants with complicated mild or moderate TBI (n = 74) or severe TBI (n = 84) were administered the NIHTB-CB, and comprised the validation sample. Scores were derived for the five fluid tests using four adjustment models: age-only, demographic-only, age-and-reading, and demographic-and-reading referenced scores.

RESULTS

Estimated premorbid ability varies depending on the reference model. Scores from each of the four reference models differentiated the comparison and TBI samples at the group level. However, performance varied by premorbid ability.

CONCLUSIONS/IMPLICATIONS

Premorbid ability affects identification of cognitive difficulties after TBI. Reading referenced scores provide an individualized estimate of the effects of premorbid ability than demographic characteristics alone. Each model identified a similar number of individuals as having cognitive difficulties; however, the models differed on which individuals had cognitive difficulties. The models had higher disagreement rates in the clinical compared with the comparison sample, particularly for individuals with lower premorbid ability. Clinical use and caveats are discussed. (PsycINFO Database Record

Neuropsychological correlates of self-reported impulsivity and informant-reported maladaptive behaviour among veterans with posttraumatic stress disorder and traumatic brain injury history

OBJECTIVE

Frontal lobe deficits resulting from traumatic brain injury (TBI) and/or posttraumatic stress disorder (PTSD) have been linked to impulsive behaviour. We sought to examine whether neuropsychological performance predicted self-reported impulsivity and informant-reported maladaptive behaviour.

METHOD

We administered the Delis-Kaplan Executive Function System (D-KEFS) to 116 Iraq/Afghanistan-era veterans diagnosed with a history of TBI and PTSD.

RESULTS

Poorer performance on D-KEFS Stroop Task (both colour and word, separately) and Trail making (letter sequencing and motor speed) tasks and higher PTSD symptom severity were associated with higher self-reported impulsivity. Trail making letter sequencing performance was negatively associated with informant-reported maladaptive behaviour. Regression analyses revealed PTSD symptom severity and Trail making letter sequencing best predicted self-reported impulsivity, even when accounting for age, sex, and education. Only Trail making letter sequencing predicted informant-reported maladaptive behaviour when accounting for other variables in the model.

CONCLUSIONS

Attention and processing speed impairments and PTSD symptom severity appear to be important predictors of impulsivity and problematic behaviour among veterans. Findings have implications for theoretical models of aggression and violence and inform the assessment and treatment of individuals with TBI and PTSD.

Item response theory analyses of the Delis-Kaplan Executive Function System card sorting subtest

In the current study, we examined the dimensionality of the 16-item Card Sorting subtest of the Delis-Kaplan Executive Functioning System assessment in a sample of 264 native English-speaking children between the ages of 9 and 15 years. We also tested for measurement invariance for these items across age and gender groups using item response theory (IRT). Results of the exploratory factor analysis indicated that a two-factor model that distinguished between verbal and perceptual items provided the best fit to the data. Although the items demonstrated measurement invariance across age groups, measurement invariance was violated for gender groups, with two items demonstrating differential item functioning for males and females. Multigroup analysis using all 16 items indicated that the items were more effective for individuals whose IRT scale scores were relatively high. A single-group explanatory IRT model using 14 non-differential item functioning items showed that for perceptual ability, females scored higher than males and that scores increased with age for both males and females; for verbal ability, the observed increase in scores across age differed for males and females. The implications of these findings are discussed.

The Trail Making Test

The Trail Making Test (TMT) is used as an indicator of visual scanning, graphomotor speed, and executive function. The aim of this study was to examine the TMT relationships with several neuropsychological measures and to provide normative data in community-dwelling participants of 55 years and older. A population-based Spanish-speaking sample of 2,564 participants was used. The TMT, Symbol Digit Test, Stroop Color–Word Test, Digit Span Test, Verbal Fluency tests, and the MacQuarrie Test for Mechanical Ability tapping subtest were administered. Exploratory factor analyses and regression lineal models were used. Normative data for the TMT scores were obtained. A total of 1,923 participants (76.3%) participated, 52.4% were women, and the mean age was 66.5 years (Digit Span = 8.0). The Symbol Digit Test, MacQuarrie Test for Mechanical Ability tapping subtest, Stroop Color–Word Test, and Digit Span Test scores were associated in the performance of most TMT scores, but the contribution of each measure was different depending on the TMT score. Normative tables according to significant factors such as age, education level, and sex were created. Measures of visual scanning, graphomotor speed, and visuomotor processing speed were more related to the performance of the TMT-A score, while working memory and inhibition control were mainly associated with the TMT-B and derived TMT scores.

Clinical neuropsychology in Israel: history, training, practice and future challenges

OBJECTIVE

This is an invited paper for a special issue on international perspectives on training and practice in clinical neuropsychology. We provide a review of the status of clinical neuropsychology in Israel, including the history of neuropsychological, educational, and accreditation requirements to become a clinical neuropsychologist and to practice clinical neuropsychology.

METHOD

The information is based primarily on the personal knowledge of the authors who have been practicing clinical neuropsychology for over three decades and hold various administrative and academic positions in this field. Second, we conducted three ad hoc surveys among clinical and rehabilitation psychologists; heads of academic programs for rehabilitation and neuropsychology; and heads of accredited service providers. Third, we present a literature review of publications by clinical neuropsychologists in Israel.

RESULTS

Most of the clinical neuropsychologists are graduates of either rehabilitation or clinical training programs. The vast majority of neuropsychologists are affiliated with rehabilitation psychology. The training programs (2-3 years of graduate school) provide solid therapeutic and diagnostic skills to the students. Seventy-five percent of the participants in this survey are employed at least part-time by public or state-funded institutions. Israeli neuropsychologists are heavily involved in case management, including vocational counseling, and rehabilitation psychotherapy. Conclusions and future goals: Although clinical neuropsychologists in Israel are well educated and valued by all health professionals, there are still several challenges that must be addressed in order to further advance the field and the profession. These included the need for Hebrew-language standardized and normalized neuropsychological tests and the application of evidence-based interventions in neuropsychological rehabilitation.

Cognitive and psychological flexibility after a traumatic brain injury and the implications for treatment in acceptance-based therapies: A conceptual review

This paper provides a selective review of cognitive and psychological flexibility in the context of treatment for psychological distress after traumatic brain injury, with a focus on acceptance-based therapies. Cognitive flexibility is a component of executive function that is referred to mostly in the context of neuropsychological research and practice. Psychological flexibility, from a clinical psychology perspective, is linked to health and well-being and is an identified treatment outcome for therapies such as acceptance and commitment therapy (ACT). There are a number of overlaps between the constructs. They both manifest in the ability to change behaviour (either a thought or an action) in response to environmental change, with similarities in neural substrate and mental processes. Impairments in both show a strong association with psychopathology. People with a traumatic brain injury (TBI) often suffer impairments in their cognitive flexibility as a result of damage to areas controlling executive processes but have a positive response to therapies that promote psychological flexibility. Overall, psychological flexibility appears a more overarching construct and cognitive flexibility may be a subcomponent of it but not necessarily a pre-requisite. Further research into therapies which claim to improve psychological flexibility, such as ACT, needs to be undertaken in TBI populations in order to clarify its utility in this group.

The Effects of Aging, Malingering, and Traumatic Brain Injury on Computerized Trail-Making Test Performance

The trail making test (TMT) is widely used to assess speed of processing and executive function. However, normative data sets gathered at different sites show significant inconsistencies. Here, we describe a computerized version of the TMT (C-TMT) that increases the precision and replicability of the TMT by permitting a segment-by-segment analysis of performance and separate analyses of dwell-time, move-time, and error time. Experiment 1 examined 165 subjects of various ages and found that completion times on both the C-TMT-A (where subjects connect successively numbered circles) and the C-TMT-B (where subjects connect circles containing alternating letters and numbers) were strongly influenced by age. Experiment 2 examined 50 subjects who underwent three test sessions. The results of the first test session were well fit by the normative data gathered in Experiment 1. Sessions 2 and 3 demonstrated significant learning effects, particularly on the C-TMT-B, and showed good test-retest reliability. Experiment 3 examined performance in subjects instructed to feign symptoms of traumatic brain injury: 44% of subjects produced abnormal completion times on the C-TMT-A, and 18% on the C-TMT-B. Malingering subjects could be distinguished from abnormally slow controls based on (1) disproportionate increases in dwell-time on the C-TMT-A, and (2) greater deficits on the C-TMT-A than on the C-TMT-B. Experiment 4 examined the performance of 28 patients with traumatic brain injury: C-TMT-B completion times were slowed, and TBI patients showed reduced movement velocities on both tests. The C-TMT improves the reliability and sensitivity of the trail making test of processing speed and executive function.

The cooking task: making a meal of executive functions

Current standardized neuropsychological tests may fail to accurately capture real-world executive deficits. We developed a computer-based Cooking Task (CT) assessment of executive functions and trialed the measure with a normative group before use with a head-injured population. Forty-six participants completed the computerized CT and subtests from standardized neuropsychological tasks, including the Tower and Sorting Tests of executive function from the Delis-Kaplan Executive Function System (D-KEFS) and the Cambridge prospective memory test (CAMPROMPT), in order to examine whether standardized executive function tasks, predicted performance on measurement indices from the CT. Findings showed that verbal comprehension, rule detection and prospective memory contributed to measures of prospective planning accuracy and strategy implementation of the CT. Results also showed that functions necessary for cooking efficacy differ as an effect of task demands (difficulty levels). Performance on rule detection, strategy implementation and flexible thinking executive function measures contributed to accuracy on the CT. These findings raise questions about the functions captured by present standardized tasks particularly at varying levels of difficulty and during dual-task performance. Our preliminary findings also indicate that CT measures can effectively distinguish between executive function and Full Scale IQ abilities. Results of the present study indicate that the CT shows promise as an ecologically valid measure of executive function for future use with a head-injured population and indexes selective executive function’s captured by standardized tests.

The sorting test of the D-KEFS in current and weight restored anorexia nervosa patients

OBJECTIVE

Efforts have been made to characterize executive functions (EF) in anorexia nervosa (AN) both in the acute stage of the illness and after weight gain, yet many questions remain. The question of verbal versus visuo-perceptual stimuli in this regard has not been adequately addressed. The aim of this study is to further examine EF in women with past and present AN and to compare their performances in verbal and visual modalities with women who have never suffered from an eating disorder.

METHOD

Thirty-five underweight AN patients, 33 weight-restored patients symptom-free for at least 2 years, and 48 healthy female controls completed the Delis-Kaplan Executive Function System Sorting Test, so as to evaluate their EF.

RESULTS

No differences were observed between the scores of women with current and past AN. Both groups scored lower than controls on most test variables. However, while in the visuo-perceptual domain the performance of the AN groups was worse than that of controls, in the verbal domain they performed similarly to them.

DISCUSSION

Women with a past or present diagnosis of AN show difficulties in visuo-perceptual EF, whereas verbal EF seem to be preserved. There may be a dissociation between verbal and visuo-perceptual EF that persists after weight restoration.

Heterogeneity in Trail Making Test performance in OEF/OIF/OND veterans with mild traumatic brain injury

This study used cluster analysis to examine variability in Trail Making Test (TMT) performance in a sample of Operation Enduring Freedom/Operation Iraqi Freedom/Operation New Dawn (OEF/OIF/OND) veterans referred for mild traumatic brain injury (mTBI). Three clusters were extracted, two of which were characterized by level of performance and the third with a unique performance pattern characterized by slow performance on the TMT B (Low B). Clusters did not differ on demographic or psychiatric variables. The Above Average cluster had better performance on measures of processing speed, working memory, and phonemic fluency compared with the Low B cluster. Results suggest that a subset of patients with mTBI perform poorly on TMT B, which subsequently predicts poorer cognitive functioning on several other neuropsychological measures. This subset may be vulnerable to cognitive changes in the context of mTBI and multiple comorbidities while a number of other patients remain cognitively unaffected under the same circumstances.

A systematic review of assessments for identifying executive function impairment in adults with acquired brain injury

PURPOSE

To synthesize quantitative findings concerning measures of executive function (EF) in adults with acquired brain injury (ABI).

METHOD

Electronic databases were searched for studies of EF assessments in adults with ABI that reported any of 3 values: likelihood ratios (LRs), standardized group mean comparisons (ds), or correlations (rs) among EF tests. Forest plots were constructed for each value.

RESULTS

Searches yielded 1,417 unique citations. Full texts of 129 articles were reviewed; 34 reported at least 1 value of interest. Nineteen positive and negative LRs were calculated from 8 studies of 8 EF measures; some point estimates were in the clinically informative range, but all confidence intervals extended beyond it. From 24 studies of 14 measures, 114 d values were calculated; d values for only 11 measures had lower bounds > 0.80. From 8 studies involving 10 EF measures, 104 correlations were reported; in only 5 cases were r(2) values > .5.

CONCLUSIONS

Strong evidence concerning diagnostic accuracy and concurrent validity of EF measures for adults with ABI is lacking. Better specification of the construct of EF as well as research aimed at improving the quality of evidence concerning EF tests are needed.

Acceptance and Commitment Therapy (ACT) for Psychological Adjustment after Traumatic Brain Injury: Reporting the Protocol for a Randomised Controlled Trial

Following a severe traumatic brain injury (TBI) there is a complex presentation of psychological symptoms which may impact on recovery. Validated treatments addressing these symptoms for this group of people are limited. This article reports on the protocol for a single-centre, two-armed, Phase II Randomised Control Trial (RCT) to address the adjustment process following a severe TBI. Participants will be recruited from Liverpool Brain Injury Rehabilitation Unit and randomly allocated to one of two groups, Acceptance and Commitment Therapy (ACT) or an active control (Befriending). The active treatment group utilises the six core processes of ACT with the intention of increasing participation and psychological flexibility and reducing psychological distress. A number of primary and secondary outcome measures, administered at assessment, post-treatment and 1-month follow-up, will be used to assess clinical outcomes. The publication of the protocol before the trial results are available addresses fidelity criterion (intervention design) for RCTs. This ensures transparency in the RCT and that it meets the guidelines according to the CONSORT statement. The protocol has also been registered on the Australian New Zealand Clinical Trials Registry ACTRN12610000851066.

Trail Making Test: regression-based norms for the Portuguese population

The main goal of this study was to produce normative data for the Portuguese population on the Trail Making Test (TMT). The study included 1,038 community-dwelling individuals aged between 18 and 93 years, who had educational backgrounds ranging from 3 to 22 years. The results showed that sex, age, and education were significantly associated with TMT performance. These demographic characteristics accounted for 57% of the performance variance at part A and 50% at part B. The normative data are presented as regression-based algorithms to adjust direct and derived test scores for sex, age, and education. The adjusted scores' percentile distributions and their correspondence with scaled scores are also provided.