Delis-Kaplan Executive Function System Tower Research Articles

85 Performance Consistency on a Measure of Sustained and Selective Attention

Objective:Attention concerns, particularly difficulties with focusing and regulating attention, are reported in diverse clinical contexts. The Ruff 2&7 Selective Attention Test (Ruff 2&7; Ruff & Allen, 1996) is a measure of sustained and selective attention that assesses automatic detection and effortful processing. The goal of this study was to create an internal consistency metric within this test and to determine cognitive predictors by evaluating associations with executive control of attention and other cognitive skills. It was hypothesized that those who are more consistent across Ruff 2&7 performance would have more robust executive functioning skills, particularly those related to regulating and directing attention and the planning and utilization of cognitive resources.Participants and Methods:The current study examined a clinical sample of 98 United States veterans with a history of mild traumatic brain injury. After excluding invalid cases (n=24), the final sample consisted of 74 veterans (Age=38.5 (8.9) years old; 13.9 (2.2) years of education; 78% male; 82% white, 7% Black, 8% Hispanic, 2% Asian). A consistency score was defined as the absolute value of the intertrial change in target hits plus errors across each pair of trials of the same stimulus type (Automatic Detection, AD, and Controlled Search, CS). Hierarchical linear regression modeling was used to evaluate the relative contributions of memory and executive functions (Rey Auditory Verbal Learning Test, Delis-Kaplan Executive Function System Tower Test, phonemic fluency, Trail Making Test B) and subjective symptom report (PTSD Checklist for DSM-5, Barkley Adult ADHD Rating Scale for DSM-IV).Results:The mean deviation scores for the two trial types were similar (AD mean=13.6, SD=5.9; CS mean=13.6, SD=5.3). In predicting consistency across AD trials, delayed recall contributed 11% unique variance (p=.013), while no other block was statistically significant. For CS trials, self-reported PTSD and inattention symptoms contributed a combined 20% of unique variance to the model (p=.007), while there were no statistically significant cognitive predictors in this model.Conclusions:Contrary to expectation, executive function measures did not explain statistically significant variance in performance across either trial type. Less consistent performance on AD trials was associated with weaker verbal memory. Less consistent performance on CS trials, which theoretically require greater executive control, was not associated with any cognitive scores, but was associated with more severe self-reported psychological and inattention symptoms. These findings buttress the conceptual distinction between AD and CS trial types, and they point to both cognitive and non-cognitive underpinnings of performance consistency.

Using the Delis–Kaplan Executive Function System Tower Test to Examine ADHD Sensitivity in Children: Expanding Analysis Beyond the Summary Score

Attention-deficit/hyperactivity disorder (ADHD) affects many children and is commonly regarded as a disorder of executive function (EF; Willcutt et al. Journal of Biological Psychiatry, 57, 1336–1346, 2005). EF is thought to be housed primarily within the brain’s prefrontal cortex (PFC), with different areas of the PFC orchestrating different EF components (Jurado and Rosselli Neuropsychology Review, 17, 213–233, 2007). Key PFC areas for this study included the dorsolateral PFC and orbitofrontal cortex. A measure on the Delis–Kaplan Executive Function System (D-KEFS), the Tower Test, has been infrequently studied with child populations, particularly those with ADHD. The limited research that does exist has primarily focused on the Tower’s summary score, overlooking available optional scores. The current study involved investigation of Tower performance in children ages 8 to 18 with ADHD (n = 252) to look for impaired scores, examine correlations with common ADHD measures, and compare Tower scores to clinical (n = 49) and normative controls (n = 110). Children with ADHD showed deficits on multiple Tower scores. Notably, more than half of the children with ADHD scored more than 1 standard deviation below the norm on the Move Accuracy Ratio (MAR) score, and children younger than 14 completed the Tower less efficiently than older children (i.e., lower MAR). Lower MAR scores were also correlated with higher parent ratings of inhibition on the Behavior Rating Inventory of Executive Function (BRIEF) and more errors of impulsivity on the Conners’ Continuous Performance Test, second edition (CPT II). Normative controls significantly outperformed children with ADHD on five of six Tower measures. The sensitivity of these optional measures was evident even while the total score was not sensitive to group differences, which highlights the importance of analyzing Tower optional scores and underscores the need for future research applying similar methods.

Neurocognitive Function in Children with Primary Hypertension after Initiation of Antihypertensive Therapy

To determine the change in neurocognitive test performance in children with primary hypertension after initiation of antihypertensive therapy. Subjects with hypertension and normotensive control subjects had neurocognitive testing at baseline and again after 1 year, during which time the subjects with hypertension received antihypertensive therapy. Subjects completed tests of general intelligence, attention, memory, executive function, and processing speed, and parents completed rating scales of executive function. Fifty-five subjects with hypertension and 66 normotensive control subjects underwent both baseline and 1-year assessments. Overall, the blood pressure (BP) of subjects with hypertension improved (24-hour systolic BP load: mean baseline vs 1 year, 58% vs 38%, P < .001). Primary multivariable analyses showed that the hypertension group improved in scores of subtests of the Rey Auditory Verbal Learning Test, Grooved Pegboard, and Delis-Kaplan Executive Function System Tower Test (P < .05). However, the control group also improved in the same measures with similar effects sizes. Secondary analyses by effectiveness of antihypertensive therapy showed that subjects with persistent ambulatory hypertension at 1 year (n = 17) did not improve in subtests of Rey Auditory Verbal Learning Test and had limited improvement in Grooved Pegboard. Overall, children with hypertension did not improve in neurocognitive test performance after 1 year of antihypertensive therapy, beyond that also seen in normotensive controls, suggesting improvements with age or practice effects because of repeated neurocognitive testing. However, the degree to which antihypertensive therapy improves BP may affect its impact upon neurocognitive function.

Prospective memory in obsessive compulsive disorder

Studies on the nature and extent of prospective memory impairment in patients with obsessive-compulsive disorder are relatively scarce. The present study examined prospective memory in patients with obsessive-compulsive disorder in comparison to patients with schizophrenia and healthy controls. Prospective memory was assessed using Memory for Intentions Screening Test (MIST). Further, the participants were administered Delis-Kaplan Executive Function System Tower Test, Wisconsin Card Sorting Test, and Stroop Test for assessing their planning ability, mental flexibility and cognitive inhibition, respectively. Monitoring was assessed by frequency of clock checking. Results indicated that as compared to healthy controls, the patients with obsessive-compulsive disorder performed poorly on both time- and event-based prospective memory tasks, whereas, patients with schizophrenia performed poorly on time-based prospective memory task only. Further, both the patient groups had comparable performance across time- and event-based tasks. Results of error analysis indicated that patients with obsessive-compulsive disorder mainly committed no response and task substitution errors, whereas patients with schizophrenia committed no response errors. Except monitoring, none of the neurocognitive variables correlated with time or event-based prospective memory in any group. The findings are discussed in the light of their implications for retraining of prospective memory deficits in patients with obsessive-compulsive disorder and schizophrenia.

Abstracts of the 57th Annual Scientific Meeting of the British Society for Haematology, 27-29 March 2017, Brighton, UK.

Background: Sickle cell anaemia (SCA) is associated with frequent episodes of vaso-occlusive pain crises, but many patients also experience chronic daily pain, which may be due to avascular necrosis of joints, bone infarction, osteomyelitis or due to intractable chronic pain without obvious pathology2 or neuropathic pain3. Not all patients experience a significant chronic pain burden4. The impact of chronic sickle cell pain on the brain is not yet clear; a recent resting-state fMRI study showed a correlation between functional connectivity of the default-mode network and number of hospitalizations for pain5. In other chronic pain conditions, reduced grey matter volume has been noted in various cortical regions involved in pain processing such as the anterior6 and posterior7-9 cingulate cortex (ACC and PCC, respectively), primary motor cortex9 (M1), primary somatosensory cortex5,6 (S1) and insula cortex. The aim of this study is to investigate the relationship between daily pain and a priori selected grey matter regions. Methods: As part of the baseline assessments for the Prevention of Morbidity in Sickle Cell Anaemia (POMS2b) phase-II trial, 52 children and adults recorded baseline daily pain and underwent neuropsychological testing and MRI in the 14 days prior to randomisation. Daily pain was recorded on a numerical scale 0-10 for 14 days. Patients were split into Low-Pain group (50% of recorded days in pain). Neuropsychological assessment was carried out using: Wechsler full-scale IQ (FSIQ), working memory index (WMI) and processing speed index (PSI), Delis-Kaplan Executive Function System Tower and Sorting subtests. Patients underwent MRI on a 3T Siemens Prisma that included T2-weighted sequences to diagnose silent cerebral infarction and a 3D T1-weighted MPRAGE. Cortical parcellation was carried out using Freesurfer. A model was fitted to the imaging data variables to investigate differences between low-pain and highpain groups, controlling for age, gender and presence of SCI and socioeconomic status10 (Index of Multiple Deprivation decile by UK postcode). Results: Five children were excluded from analysis (poor quality data or braces artefact). The final sample was 47 children and adults with SCA. There was a significant correlation with percentage of days in pain and age (r = 0.53, p = 0.0001). In the low-pain group, 11 patients reported no pain during the recorded days. High-pain patients had significantly lower WMI and a trend for lower FSIQ, PSI, Sorting-correct sorts and Sorting-free sorting description. High-pain patients had significantly reduced cortical thickness in the mean cortex of the left and right hemispheres, and significantly thinner cortex in the bilateral precuenus, bilateral PCC, left M1 and right caudal ACC. There was a trend for positive correlation between average pain and right-hemisphere rostral ACC thickness. Conclusion: This study is the first to describe structural brain abnormalities in patients with high burden of sickle cell pain. These patients are part of a 6-month randomised controlled trial of overnight respiratory support with cognitive and pain endpoints as well as repeat MRI; this study may provide structural biomarkers that may parallel amelioration of chronic daily pain.

Thalamic Functional Connectivity in Mild Traumatic Brain Injury: Longitudinal Associations With Patient-Reported Outcomes and Neuropsychological Tests

Objectives(1) To examine differences in patient-reported outcomes, neuropsychological tests, and thalamic functional connectivity (FC) between patients with mild traumatic brain injury (mTBI) and individuals without mTBI and (2) to determine longitudinal associations between changes in these measures. DesignProspective observational case-control study. SettingAcademic medical center. ParticipantsA sample (N=24) of 13 patients with mTBI (mean age, 39.3±14.0y; 4 women [31%]) and 11 age- and sex-matched controls without mTBI (mean age, 37.6±13.3y; 4 women [36%]). InterventionsNot applicable. Main Outcome MeasuresResting state FC (3T magnetic resonance imaging scanner) was examined between the thalamus and the default mode network, dorsal attention network, and frontoparietal control network. Patient-reported outcomes included pain (Brief Pain Inventory), depressive symptoms (Patient Health Questionnaire-9), posttraumatic stress disorder ([PTSD] Checklist – Civilian Version), and postconcussive symptoms (Rivermead Post-Concussion Symptoms Questionnaire). Neuropsychological tests included the Delis-Kaplan Executive Function System Tower test, Trails B, and Hotel Task. Assessments occurred at 6 weeks and 4 months after hospitalization in patients with mTBI and at a single visit for controls. ResultsStudent t tests found increased pain, depressive symptoms, PTSD symptoms, and postconcussive symptoms; decreased performance on Trails B; increased FC between the thalamus and the default mode network; and decreased FC between the thalamus and the dorsal attention network and between the thalamus and the frontoparietal control network in patients with mTBI as compared with controls. The Spearman correlation coefficient indicated that increased FC between the thalamus and the dorsal attention network from baseline to 4 months was associated with decreased pain and postconcussive symptoms (corrected P<.05). ConclusionsFindings suggest that alterations in thalamic FC occur after mTBI, and improvements in pain and postconcussive symptoms are correlated with normalization of thalamic FC over time.

C-44 * Improvement in Executive Function following Traumatic Brain Injury in Children

Objective: Executive function deficits are common following traumatic brain injury (TBI) in children. Some reports indicate that executive function improves following TBI, although factors that contribute to recovery continue to be investigated. In this study we examine improvement in performance on the Delis–Kaplan Executive Function System (DKEFS) Tower task, a measure of planning and problem solving abilities, at two time points following TBI to examine magnitude of improvement and associated factors. Method: Participant included 32 children with TBI (Age 14.52, SD = 2.73, 59.4% male). Based on Glasgow coma scale scores most children sustained severe brain injuries (GCS = 6.27, N = 26). Initial evaluation occurred an average of 27.4 days after injury upon admission to a rehabilitation program, and then again 57.7 days later when discharged from the program. Results: Repeated measure ANOVA indicated significant improvement in DKEFS Tower performance (F = 12.872, p > .001). Single sample t-tests indicated the groups performed significantly poorer than the standard sample at intake (p < .002) with no significant difference at discharge. Correlations between injury and recovery related variable with DKEFS tower performance were not significant, although Nonverbal IQ and Nonverbal Memory abilities significantly correlated with DKEFS performance at intake. Conclusion(s): Finding suggest that improvement in executive function does occur in response to rehabilitation, although the current study was not capable of examining how practice effects may influence improvement in DKEFS scores. Future research may examine this matter further and investigate whether similar improvements occur in other areas of executive function.

An occupation-based strategy training approach to managing age-related executive changes: a pilot randomized controlled trial

Objective: To determine the feasibility of recruitment and retention of healthy older adults and the effectiveness of an intervention designed to manage age-related executive changes. Design: A pilot randomized controlled trial. Setting: Research centre and participants’ homes. Participants: Nineteen healthy, community dwelling older adults with complaints of cognitive difficulties and everyday problems, but no evidence of mild cognitive impairment, dementia or depression on objective testing. Interventions: Seventeen hours of group and individual training. Participants in the experimental arm received education about self-management, successful aging and an occupation-based meta-cognitive strategy-training program. Participants in the control arm received education about brain health and participated in cognitively stimulating exercises. Main measures: Changes on untrained, everyday life goals were identified using the Canadian Occupational Performance Measure. Generalization of benefits was measured using the Stanford Chronic Disease Questionnaire, general self-efficacy and changes in executive function (Delis-Kaplan Executive Function System Tower Test, Word Fluency and Trail-Making Test). Results: 20% (19/96) of healthy older adults approached were eligible, consented and were enrolled in the study, 90% (17/19) were retained to three-month follow-up. Participants in the experimental arm reported significantly more improvement on untrained goals (11/22 compared with 9/46, χ2=4.92, p<0.05), maintenance of physical activity (p<0.05) and better preparation for doctors’ visits (p<0.05) relative to the control group. There were no significant between group differences on objective measures of executive function. Conclusions: These data support the feasibility of a larger trial where a sample of 72 (36 participants in each arm) would be required to confirm or refute these findings.

Executive Functioning: A Comparison of the Tower of LondonDX and the D-KEFS Tower Test

This study compared the Delis-Kaplan Executive Function System (D-KEFS) Tower Test to the Tower of London (TOL)DX in assessing executive functioning (EF) during a psycho-educational assessment by examining students’ performances on both tests. Forty-two university students were administered both tests in a counterbalanced order. Findings indicate that students did not perform significantly differently on the D-KEFS Tower Test than on the TOLDX, but that the tests only shared 22% of their variance. Although the moderate correlation found between overall achievement scores indicates that the D-KEFS Tower Test assesses some similar EF abilities as the TOLDX, the different problem spaces between these tests may be tapping into different constructs and may account for the non-shared variance.

The effects of verbalisation on cognitive performance in schizophrenia: A pilot study using tasks from the Delis Kaplan Executive Function System

Cognitive impairment is common in schizophrenia, and has adverse effects on functional outcome. Cognitive remediation strategies in which people with schizophrenia speak aloud (verbalise) during task performance have demonstrated some success in improving performance on the Wisconsin Card Sorting Test. This study extends previous research by assessing whether verbalisation also improves performance on tasks selected from the Delis-Kaplan Executive Function System (D-KEFS). Twenty two subjects with schizophrenia participated in the study. We used a within subjects design to compare performance on the D-KEFS Tower Test and Trail Making Test when participants (a) produced concurrent verbalisation, or (b) remained silent. Results demonstrated selective benefits of verbalisation on a neuropsychological task requiring multiple executive functions (number-letter switching task), while performance on tasks requiring simpler single-component cognitive functions (visual scanning and motor speed tasks) was adversely affected. The effects of verbalisation on the cognitive task performance of patients with schizophrenia differ depending on the nature of the task. Benefits are seen in tests of executive skills but performance worsens in single component cognitive tasks. When developing cognitive remediation strategies for people with schizophrenia, consideration should be given to the nature and cognitive demands of each task before recommending verbalisation strategies.