Delis-Kaplan Executive Function System Research Articles

Evaluating neurocognitive outcomes in out-of-hospital cardiac arrest survivors: A comparative study of performance-based and reported measures

AimsTo (1) describe the prevalence of cognitive dysfunctions using performance-based and reported measures, and (2) explore the correlations between selected performancebased, patient-reported, and observer-reported neurocognitive outcome measures three months after hospital discharge in a population of out-of-hospital cardiac arrest (OHCA) survivors. MethodsData from 193 OHCA survivors was derived from the Danish multicenter REVIVAL cohort study. At three months, four subtests of the performance-based Delis-Kaplan Executive Function System (D-KEFS) (Trail making, Color-word interference, Verbal fluency, and Figure design), the patient-reported Behavior Rating Inventory of Executive Function − Adult (BRIEF-A), and the observer-reported 16-item Short Form (SF) Informant Questionnaire on Cognitive Decline after Cardiac Arrest (SF-16 IQCODE-CA) were collected. Spearman’s rank coefficient correlation analysis was performed to examine correlations between D-KEFS, BRIEF-A, and SF-16 IQCODECA. ResultsOverall, 21% of survivors exhibited impairment in executive functioning using the DKEFS subtest Color-word interference, while only 9% self-reported executive impairment (BRIEF-A) and 7% of relatives reported cognitive decline (SF-16 IQCODECA) in survivors at three months post-arrest. All correlations between D-KEFS, BRIEFA, and SF-16 IQCODE-CA were negligible to low. ConclusionThe results of this REVIVAL substudy suggest that although the performance-based and reported measures did not correlate, dual neurocognitive screening tools containing both a self-reported and an informant-reported version may have the potential to detect executive discrepancies in the return to everyday life and guide targeted neurorehabilitation after OHCA.

Cognitive functioning in adult psychiatric patients with and without attention-deficit/hyperactivity disorder.

Studies of cognitive functioning in patients with attention-deficit/hyperactivity disorder (ADHD) have often used healthy comparison groups. The present study examines cognitive profiles, including general intellectual and executive functions, in a young adult psychiatric outpatient clientele with ADHD and evaluates whether their cognitive profiles can help differentiate them from patients with non-ADHD-associated psychiatric disorders. The study group comprised 141 young adult psychiatric patients (age range 18-25 years) of whom 78 had ADHD. Comprehensive neuropsychological assessment included the Wechsler Adult Intelligence Scale, 4th version and subtests from Delis-Kaplan Executive Function System. Clinical psychiatric assessments and diagnostic evaluation were performed. The ADHD group (including all subtypes) had significantly lower verbal comprehension and full-scale intelligence quotient than the non-ADHD group. Tests measuring working memory or executive function did not separate those with and without ADHD. The results of our study suggest that, except for the need to establish overall cognitive performance level, the clinical implication of testing is small if the purpose is to "rule out" an ADHD diagnosis.

A Potential Measure of Premorbid Functioning: Evaluating the Construct Validity of the Author and Magazine Recognition Tests.

To establish convergent and discriminant validity for a combined measure of print exposure (i.e., Author Recognition Test and Magazine Recognition Test [ART/MRT]) and assess its potential utility for estimating premorbid cognitive functioning. Community-dwelling older adults (N = 84; 95% non-Hispanic White) completed the ART/MRT, Test of Premorbid Functioning (ToPF), Dementia Rating Scale - 2nd Edition (DRS-2), Hopkins Verbal Learning Test - Revised (HVLT-R-DR), and select subtests from the Delis-Kaplan Executive Functioning System (D-KEFS) as measures of executive functioning (i.e., D-KEFS-EF) and processing speed (i.e., D-KEFS-PS). Pearson correlations and linear regressions were used to examine the relationships between the ART/MRT, cognition, and demographics. Cognitive scores, with the exception of HVLT-R-DR, were positively correlated with ART/MRT score such that better cognitive performance was associated with greater print exposure (range r = 0.39-0.49). ART/MRT score was positively correlated with years of education and negatively correlated with age. ToPF and DRS-2 differentially and uniquely predicted ART/MRT score beyond the other cognitive and demographic variables and beyond each other. Findings indicate that measures of print exposure reflect crystallized knowledge but may also capture fluid abilities that may be more vulnerable to age-related decline or neurodegeneration. Assessment of print exposure may offer an alternative to word reading measures that may be inappropriate for translation into other languages and for use with individuals with certain language difficulties.

Temporal Profile of Serum Neurofilament Light (NF-L) and Heavy (pNF-H) Level Associations With 6-Month Cognitive Performance in Patients With Moderate-Severe Traumatic Brain Injury.

Identification of biomarkers of cognitive recovery after traumatic brain injury (TBI) will inform care and improve outcomes. This study assessed the utility of neurofilament (NF-L and pNF-H), a marker of neuronal injury, informing cognitive performance following moderate-to-severe TBI (msTBI). Level 1 trauma center and outpatient via postdischarge follow-up. N = 94. Inclusion criteria: Glasgow Coma Scale score less than 13 or 13-15 with clinical evidence of moderate-to-severe injury traumatic brain injury on clinical imaging. Exclusion criteria: neurodegenerative condition, brain death within 3 days after injury. Prospective observational study. Blood samples were collected at several time points post-injury. Cognitive testing was completed at 6 months post-injury. Serum NF-L (Human Neurology 4-Plex B) pNF-H (SR-X) as measured by SIMOA Quanterix assay. Divided into 3 categorical time points at days post-injury (DPI): 0-15 DPI, 16-90 DPI, and >90 DPI. Cognitive composite comprised executive functioning measures derived from 3 standardized neuropsychological tests (eg, Delis-Kaplan Executive Function System: Verbal Fluency, California Verbal Learning Test, Second Edition, Wechsler Adult Intelligence Scale, Third Edition). pNF-H at 16-90 DPI was associated with cognitive outcomes including a cognitive-executive composite score at 6 months (β = -.430, t34 = -3.190, P = .003). Results suggest that "subacute" elevation of serum pNF-H levels may be associated with protracted/poor cognitive recovery from msTBI and may be a target for intervention. Interpretation is limited by small sample size and including only those who were able to complete cognitive testing.

Computerized assessment of executive functioning: Validation of the CNS Vital Signs executive functioning scores in a sample of community-dwelling older adults

Objective: Computerized assessment of cognitive functioning has gained significant popularity over recent years, yet options for clinical assessment of executive functioning (EF) are lacking. One computerized testing platform, CNS Vital Signs (CNS-VS), offers tests designed to measure EF but requires further validation. The goal of the present study was to validate CNS-VS executive scores against standard clinical measures of EF. We also sought to determine whether a modified CNS-VS composite score that included variables purported to measure inhibition, switching, and working memory would outperform the currently available CNS-VS Executive Function Index. Method: A sample of 73 cognitively healthy older adults completed four tests from the Delis-Kaplan Executive Function System, the Digit Span subtest from the Wechsler Adult Intelligence Scale-fourth edition, and three CNS-VS tasks purported to measure inhibition, switching, and working memory. Results: Performances on the CNS-VS tests were predicted by performances on standard paper-and-pencil measures. Although the currently available CNS-VS Executive Function Index predicted unique variance in a well-validated paper-and-pencil EF composite score, our Modified CNS-VS EF composite accounted for unique variance above and beyond the original CNS-VS Executive Function Index, while the reverse was not true. Conclusions: The present results support the construct validity of CNS-VS EF tests but also suggest that modifications to their current composite scores would improve the prediction of EF performance.

Cognition and Functional Capacity: An Initial Comparison of Veteran and Non-Veteran Older Adults.

The U.S. Military Veterans aged 65 and older comprise an estimated 43% of the 22 million living Veterans in the United States. Veterans have high rates of physical, psychiatric, and social challenges, but it is not known whether Veteran status confers additional risk for cognitive or functional impairments in later life. Thus, this investigation specifically compared older Veterans with their non-Veteran peers in cognitive functioning and performance-based functional capacity. Participants (N = 110; 29 Veterans and 81 non-Veterans) were part of a larger longitudinal study on biopsychosocial functioning in independently living older adult residents of a Continuing Care Senior Housing Community. The University of California San Diego Institutional Review Board approved the study and all participants provided written informed consent. Participants provided demographic and mental health information and were administered a comprehensive neuropsychological battery. Functional capacity was assessed using the UCSD Performance-Based Skills Assessment-Brief (UPSA-B), which uses financial and communication role-plays to assess everyday functioning skills. Neuropsychological scores were appropriately normed prior to analysis. Multivariate Analyses of Variances with post hoc t-tests and an Analysis of Covariance were used to examine neuropsychological and functional capacity differences, respectively, between Veterans and non-Veterans. Veterans did not differ from non-Veterans in educational attainment (16.4 years versus 15.5 years, P = 0.110), but they were significantly older (mean age 86.9 years ± 5.7, versus 81.74 years ± 6.53; P < 0.001) and were more likely to be male (X2 [1, N = 110] = 62.39, P < 0.001). Thus, though neuropsychological norms already accounted for demographic differences in our participants, age and sex were controlled in the Analysis of Covariance predicting UPSA-B score from Veteran status. Results suggested that, compared to non-Veterans, Veterans had significantly worse performance in the list learning portion of a test of verbal memory (Hopkins Verbal Learning Test-Revised, Total Recall; t = 2.56, P = 0.012, d = 0.56). Veterans and non-Veterans did not significantly differ in performance on the delayed recall portion of the verbal learning test and did not differ on a cognitive screening test (Montreal Cognitive Assessment) or on measures of premorbid intellectual functioning (Wide Range Achievement Test-4 Reading), language (Boston Naming Test, Verbal Fluency), visual memory (Brief Visuospatial Memory Test-Revised), attention/working memory (WAIS-IV Digit Span), processing speed (WAIS-IV Digit Symbol Coding), executive function (Delis-Kaplan Executive Function System Trails and Color-Word Test), or functional capacity (UPSA-B). Because our examination of multiple outcomes might have inflated Type I error, we performed a post hoc adjustment of P values using Benjamini-Hochberg procedures and the group difference in verbal learning remained significant. Despite largely similar function in most domains, Veterans performed significantly more poorly in verbal list learning than their non-Veteran peers. Additional attention should be given to the understanding, assessment, and possible treatment of learning and memory differences in older Veterans, as this may be an area in which Veteran status confers additional risk or vulnerability to decline. This is the first study to compare objective neuropsychological and functional performance between older (age 65+) US Veterans and non-Veterans.

The influence of depression and anxiety on cognition in people with multiple sclerosis: a cross-sectional analysis.

There are conflicting findings about the relationships between depression, anxiety, and cognitive dysfunction in people with multiple sclerosis (MS), and a paucity of research has examined the cumulative influence on cognition of depression plus anxiety. This study aimed to determine whether elevated symptoms of depression and anxiety alone or in combination are associated with worse cognition in people with MS. In this cross-sectional analysis, people with MS consecutively seen at a tertiary neuropsychiatry clinic completed the Hospital Anxiety and Depression Scale for symptoms of depression (HADS-D) and anxiety (HADS-A), and the Minimal Assessment of Cognitive Function in MS for cognitive indices. Accounting for covariates, regression models predicted cognitive indices from scores for HADS-D, HADS-A, and the interaction. Of 831 people with MS, 72% were female, mean age was 43.2years, and median Expanded Disability Status Scale score was 2.0. Depressive symptoms were independently predictive of lower verbal fluency (Controlled Oral Word Association Test, p < 0.01), verbal learning (California Verbal Learning Test-II (CVLT-II) total learning, p = 0.02), verbal delayed recall (CVLT-II delayed recall, p < 0.01), and processing speed (Symbol Digit Modalities Test, p < 0.01; three-second Paced Auditory Serial Addition Test (PASAT), p = 0.05; two-second PASAT, p = 0.01). Anxiety in people with depression predicted decreased visuospatial function (Judgment of Line Orientation, p = 0.05), verbal learning (p < 0.01), verbal delayed recall (p < 0.01), visuospatial recall (Brief Visuospatial Memory Test-Revised, p = 0.02), and executive function (Delis-Kaplan Executive Function System, p < 0.01). Anxiety alone was not independently predictive of cognition. In conclusion, depression, especially with comorbid anxiety, is associated with cognitive dysfunction in people with MS.

Cognitive flexibility is associated with sickness resilience.

Psychological constructs related to health outcomes and well-being, such as metacognitive beliefs, have been linked to executive functions in general, and cognitive flexibility more specifically. However, such effects have previously only been discussed on a theoretical level and behavioral flexibility has most often been measured through self-report, only approximating information processing capacities. Objectively measured executive functions may be a more potent predictor of health outcomes. We set out to test whether cognitive flexibility capacity was associated with sick leave in a medium sized company. We included 111 subjects of widely different occupations and assessed their executive functions using Delis-Kaplan Executive Function System test battery (D-KEFS). To assess cognitive flexibility capacity, we included Design Fluency (DF) and Verbal Fluency (VF) and computed these into an index of cognitive flexibility (DFVF). Detailed information on sick leave for the last 5 years was gathered from the company. Our results showed that there was a significant negative correlation between DFVF and sick leave [rs(109) = -0.23, p = 0.015] in the full group as well as in the group that had at least 1 day of sick leave [rs(72) = -0.25, p = 0.03]. The results withstood adjustment for sex, age, occupation, and several core executive functions as well as autistic and ADHD-traits. The results remained for separate analyses using DF or VF. Our main findings were conceptually replicated in a group of bipolar disorder patients. This study shows that objectively measured capacity of cognitive flexibility is associated with key health outcomes such as sick leave.

Treatment of Refractory Bipolar Depression With Stereotactic Radiosurgery Targeting the Subgenual Cingulate Cortex.

Background The subgenual cingulate cortex (SGC) has been identified as a key structure within multiple neural circuits whose dysfunction is implicated in the neurobiology of depression. Deep brain stimulation in the SGC is thought to reduce and normalize local metabolism, causing normalization of circuit behavior and an improvement in depressive symptoms. We hypothesized that nonablative stereotactic radiosurgery (SRS) to the SGC would reduce local metabolism and reduce the severity of depression in patients with treatment-resistant bipolar depression. Methods Under the FDA's Humanitarian Device Exemption program, patients were screened for inclusion and exclusion criteria. Three volunteers meeting the criteria provided informed consent. Bilateral SGC targets were irradiated to a maximum dose of 75 Gy in one fraction. Subjects were followed for one year following the procedure with mood assessments (Hamilton Depression Rating Scale (HDRS), Clinical Global Impression-Improvement, Clinical Global Impression-Severity, and Young Mania Rating Scale), neurocognitive testing (Delis-Kaplan Executive Function System, Wechsler Adult Intelligence Scale III digit span, and California Verbal Learning Test II), and imaging. Further imaging was completed approximately two years after the procedure. Clinical improvement was defined as a ≥50% reduction in HDRS. Results Two of the three subjects showed clinical improvement in depressive symptoms during the follow-up period, while one subject showed no change in symptom severity. One of three subjects was hospitalized for the emergence of an episode of psychotic mania after discontinuing antipsychotic medications against medical advice but promptly recovered with the reinstitution of an antipsychotic. Sequential assessments did not reveal impairment in any cognitive domain assessed. For one of the three subjects, MRI imaging showed evidence of edema at 12 months post-SRS, which resolved at 22 months post-procedure. In a second of three patients, there was evidence of local edema at the target site at long-term follow-up. All imaging changes were asymptomatic. Conclusion Radiosurgical targeting of the SGC may be a noninvasive strategy for the reduction of severe depression in treatment-resistant bipolar disorder. Two out of three patients showed clinical improvement. While these results are promising, further study, including improvements in target selection and dosing considerations, is needed.

Detecting High-Dose Methotrexate-Induced Brain Changes in Pediatric and Young Adult Cancer Survivors Using [18F]FDG PET/MRI: A Pilot Study.

Significant improvements in treatments for children with cancer have resulted in a growing population of childhood cancer survivors who may face long-term adverse outcomes. Here, we aimed to diagnose high-dose methotrexate-induced brain injury on [18F]FDG PET/MRI and correlate the results with cognitive impairment identified by neurocognitive testing in pediatric cancer survivors. Methods: In this prospective, single-center pilot study, 10 children and young adults with sarcoma (n = 5), lymphoma (n = 4), or leukemia (n = 1) underwent dedicated brain [18F]FDG PET/MRI and a 2-h expert neuropsychologic evaluation on the same day, including the Wechsler Abbreviated Scale of Intelligence, second edition, for intellectual functioning; Delis-Kaplan Executive Function System (DKEFS) for executive functioning; and Wide Range Assessment of Memory and Learning, second edition (WRAML), for verbal and visual memory. Using PMOD software, we measured the SUVmean, cortical thickness, mean cerebral blood flow (CBFmean), and mean apparent diffusion coefficient of 3 different cortical regions (prefrontal cortex, cingulate gyrus, and hippocampus) that are routinely involved during the above-specified neurocognitive testing. Standardized scores of different measures were converted to z scores. Pairs of multivariable regression models (one for z scores < 0 and one for z scores > 0) were fitted for each brain region, imaging measure, and test score. Heteroscedasticity regression models were used to account for heterogeneity in variances between brain regions and to adjust for clustering within patients. Results: The regression analysis showed a significant correlation between the SUVmean of the prefrontal cortex and cingulum and DKEFS-sequential tracking (DKEFS-TM4) z scores (P = 0.003 and P = 0.012, respectively). The SUVmean of the hippocampus did not correlate with DKEFS-TM4 z scores (P = 0.111). The SUVmean for any evaluated brain regions did not correlate significantly with WRAML-visual memory (WRAML-VIS) z scores. CBFmean showed a positive correlation with SUVmean (r = 0.56, P = 0.01). The CBFmean of the cingulum, hippocampus, and prefrontal cortex correlated significantly with DKEFS-TM4 (all P < 0.001). In addition, the hippocampal CBFmean correlated significantly with negative WRAML-VIS z scores (P = 0.003). Conclusion: High-dose methotrexate-induced brain injury can manifest as a reduction in glucose metabolism and blood flow in specific brain areas, which can be detected with [18F]FDG PET/MRI. The SUVmean and CBFmean of the prefrontal cortex and cingulum can serve as quantitative measures for detecting executive functioning problems. Hippocampal CBFmean could also be useful for monitoring memory problems.

The latent structure of the Delis-Kaplan system for autism.

A core feature of autism is deficits in executive functioning (EF), including difficulty with planning, cognitive flexibility, and working memory. Despite a growing need for evidence-based assessments of EF for autism populations, statistical models of many commonly used measures of EF, including the Delis-Kaplan Executive Function System (D-KEFS), have not been investigated for a sample of autistic participants. The purpose of this study was to address a gap in the literature regarding the latent structure of the D-KEFS in a sample of autistic individuals. The D-KEFS is one of the most widely used clinical assessments of executive function, but its factor structure has not been examined in a sample of autistic participants. Reliability analyses were performed for sample subgroups based on participants' clinical and demographic characteristics, including IQ, autism severity, age, and race/ethnicity. Verbal Fluency (VF) was found to consistently decrease or not affect the overall reliability score. Additionally, one- and two-factor structure models were tested for the D-KEFS with a sample of autistic participants. The one-factor model was not found to be a good fit for the data. However, the two-factor model, with Cognitive Flexibility and Abstraction latent factors, was found to fit the data relatively well. This two-factor model was reexamined excluding the VF observed variable, resulting in a better overall model fit. Communication deficits are a common feature of autism, which explains why the VF task, that requires participants to produce novel words, may not be an adequate measure of executive function for autism populations.

Six elements test vs D-KEFS: what does "Ecological Validity" tell us?

Extensive research shows that tests of executive functioning (EF) predict instrumental activities of daily living (IADLs) but are nevertheless often criticized for having poor ecological validity. The Modified Six Elements Test (MSET) is a pencil-and-paper test that was developed to mimic the demands of daily life, with the assumption that this would result in a more ecologically valid test. Although the MSET has been extensively validated in its ability to capture cognitive deficits in various populations, support for its ability to predict functioning in daily life is mixed. This study aimed to examine the MSET's ability to predict IADLs assessed via three different modalities relative to traditional EF measures. Participants (93 adults aged 60 - 85) completed the MSET, traditional measures of EF (Delis-Kaplan Executive Function System; D-KEFS), and self-reported and performance-based IADLs in the lab. Participants then completed three weeks of IADL tasks at home, using the Daily Assessment of Independent Living and Executive Skills (DAILIES) protocol. The MSET predicted only IADLs completed at home, while the D-KEFS predicted IADLs across all three modalities. Further, the D-KEFS predicted home-based IADLs beyond the MSET when pitted against each other, whereas the MSET did not contribute beyond the D-KEFS. Traditional EF tests (D-KEFS) appear to be superior to the MSET in predicting IADLs in community-dwelling older adults. The present results argue against replacing traditional measures with the MSET when addressing functional independence of generally high-functioning and cognitive healthy older adult patients.

Moderate-to-Vigorous Physical Activity and Response Inhibition Predict Balance in Adults with Attention Deficit/Hyperactivity Disorder.

Background: Some evidence indicates that adults with attention deficit hyperactivity disorder (ADHD) may have balance impairments. This study examined the associations between moderate-to-vigorous physical activity (MVPA), response inhibition (RI), and static balance in this population while off and on psychostimulant medication (PS). Methods: Participants (n = 40; 30 females; M age = 29.0; SD = 6.3 years) wore an ActiGraph GT9X-link around their waist to estimate MVPA levels (minutes/day). To assess RI, participants completed the Delis-Kaplan Executive Function System (D-KEFS) subtests Trail-Making Test (TMT) and Color-Word Interference Test (CWIT). To evaluate static balance, participants completed postural sway area (cm2) assessments in four conditions: feet-apart eyes-open (FAEO), feet-apart eyes-closed (FAEC), feet-together eyes-open (FTEO), and feet-together eyes-closed (FTEC). Participants also completed the single-leg standing tests (seconds) with eyes open (SLEO) and with eyes closed (SLEC). Results: When off medication, MVPA significantly predicted SLEC (β = 0.30; p = 0.017). MVPA and TMT significantly predicted FTEO, explaining ~19% of the variance in FTEO; both MVPA and TMT were significant predictors (β = -0.33, p = 0.027 and β = -0.31, p = 0.039, respectively). When on medication, TMT significantly predicted FAEC (β = 0.17; p = 0.047). Conclusions: MVPA and RI may be effective parameters in predicting static balance in adults with ADHD when off medication only.

Birth-Related Risk Factors Impact Cognitive and Academic Outcomes in Children with Sickle Cell Disease

Pre- and peri-natal-related risk factors are associated with slowed neurocognitive development and increased risk of learning difficulties in the general population. A recent study reported expressive language deficits were associated with preterm birth in young children with sickle cell disease (SCD) (Bills et al., 2021); however, no studies to date have examined the long-term impact of low birth weight in children and adolescents with SCD. In this cohort study, we examined associations between low birth weight (&amp;lt;2500g) and cognitive and academic outcomes, including formal school support services (i.e., 504 Plan or Individual Education Program), in children with SCD. Gestational age and neonatal intensive care unit (NICU) admission were investigated as covariates. Participants were children ages 8-18 years old with SCD enrolled in the Sickle Cell Clinical Research and Intervention Program (SCCRIP), an observational cohort study of clinical outcomes in SCD. Participants received targeted neurocognitive evaluations as standard of care every 3-4 years. Performance-based neurocognitive measures were used to assess cognitive and academic abilities, including the Wechsler Abbreviated Scale of Intelligence, Second Edition; Wechsler Intelligence Scale for Children, Fourth and Fifth Editions; Wechsler Adult Intelligence Scale, Fourth Edition; Delis Kaplan Executive Function System; Conners Continuous Performance Test, Second and Third Editions; and Woodcock-Johnson Tests of Achievement, Third and Fourth Editions. Multivariable generalized linear regression examined associations between birth-related risk factors (i.e., birth weight, gestational age, and NICU admission) and cognitive outcomes, academic achievement, and need for school support services after adjusting for age, sex, hydroxyurea treatment, sickle genotype, and socioeconomic status. P-values &amp;lt;0.05 were considered significant. False discovery rate-adjusted p-values or q-values were calculated across the outcomes and all birth-related risk factors to correct for multiple corrections. Of the 326 participants in SCCRIP who completed neurocognitive evaluations, 282 children had normal birth weight (HbSS/HbSβ 0thalassemia=56%) and 44 children were born with low birth weight (HbSS/HbSβ 0=45%). Birth weight groups (&amp;lt;2500g and &amp;gt;2500g) were matched for demographic and disease characteristics (Table 1). The mean age at time of cognitive evaluation was 11.16 (SD= 3.27) years and half of participants were male (51%). Low birth weight was associated with worse word reading (p=0.011; Table 2). Across all participants, admission in the NICU was associated with lower verbal reasoning (p=0.022), processing speed (p=0.017), working memory (p=0.044), word reading (p=0.021), and math fluency (p=0.05). Similarly, across all participants, earlier gestational age was associated with lower verbal fluency (p=0.011). Low birth weight and gestational age predicted need for school support services (p=0.003 and p=0.007, respectively). History of birth-related risk factors should be considered a comorbidity for neurodevelopmental differences in SCD. Specifically, children with SCD who are born with low birth weight or admitted to the NICU are at increased risk for difficulties with processing speed, working memory, language, and academics. The need for formal school support services in SCD is associated with gestational age and birth weight.

36 Dispersion vs. inconsistency: Investigating the relationship between different forms of intra-individual variability in community-dwelling older adults

Objective:There are two forms of intra-individual variability (IIV) in the literature: inconsistency, or variability on one task across many time points, and dispersion, or variability across many tasks at one time point. These forms of IIV are often lumped together into one construct, but there is limited evidence supporting this practice, as few studies have examined the relationship between these measures. Additionally, it is not clear how stable these constructs are over time. Therefore, the goal of the present study was (1) to explore the relationship between (a) inconsistency and dispersion and (b) IIV and mean performance, and (2) to determine whether these relationships are stable over a one- to two-year follow-up interval.Participants and Methods:A total of 123 community-dwelling older adults (Mage=69.5, Meducation=15.6 years) from an archival database completed the Push-Turn-Taptap task to assess inconsistency and the Delis-Kaplan Executive Functioning System (D-KEFS) to assess dispersion. These measures were selected because both are highly executive, thereby allowing us to hold the cognitive domain constant across forms of IIV. Dispersion was calculated by taking the standard deviation of the executive conditions of four D-KEFS subtests (Verbal Fluency, Design Fluency, Trail Making, and Color Word Interference). Follow-up data were collected one to two and a half years after baseline. Bivariate and partial correlations controlling for time to follow-up were examined.Results:Inconsistency and dispersion were not correlated at baseline but were weakly correlated at follow-up (r=.281, p=.012). Additionally, both forms of IIV were moderately correlated with themselves across the follow-up interval (inconsistency: r=.450, p&lt;.001; dispersion: r=.448, p&lt;.001). The partial correlations were nearly identical to bivariate correlations.Additionally, inconsistency was correlated with poorer mean executive functioning (EF) performance on both the PTT (baseline: r=.281, p&lt;.001, follow-up: r=.435, p&lt;.001) and D-KEFS (baseline: r= -.270, p=.003, follow-up: r=-.573, p&lt;.001). In contrast, dispersion was correlated with mean EF performance only on the D-KEFS at baseline (r= -.292, p&lt;.001) but with both measures at follow-up (PTT: r=.232, p=.039; D-KEFS: r= -.378, p&lt;.001). When controlling for follow-up interval, inconsistency was no longer correlated with baseline mean PTT performance, but all other relationships remained the same (i.e., dispersion and inconsistency displayed the same pattern of correlations with mean EF).Conclusions:Although inconsistency and dispersion are both forms of IIV, they are weakly related. In other words, although they may have shared mechanisms, these two methods of measuring IIV likely represent different constructs. In the future, authors should take care to specify the form of IIV being investigated in their publications rather than referring to either form as IIV generally. Additionally, both forms of IIV are weakly to moderately correlated with mean EF performance, indicating that IIV is related to but separate from mean-level performance. Interestingly, IIV and mean performance were more strongly correlated at follow-up, which may be suggestive of incipient cognitive decline. Lastly, it seems that both inconsistency and dispersion are somewhat stable across a one- to two-year follow-up interval, suggesting that IIV may be a trait-level construct to some extent. However, IIV may also be influenced by state-level contextual factors, and more research examining the stability of and contributors to IIV is necessary.

24 Longitudinal Neuropsychological Functioning in Gulf War Veterans Exposed to Neurotoxicants and War-Related Trauma

Objective:Gulf War (GW) veterans were exposed to many neurotoxicants during the 1990-1991 Gulf War. Neurotoxicants included: chemical warfare such as sarin nerve gas, combustion byproducts from oil well fires and diesel fuels from tent heaters, pesticides, and prophylactic anti- nerve gas pyridostigmine bromide pills (PB); all of which have been associated with both cognitive and mood concerns. There are few longitudinal studies that have examined cognitive functioning regarding these toxicant exposures. In our longitudinal Fort Devens cohort, we found decrements over time in the area of verbal learning and memory but no differences in measures of nonverbal memory and executive function. To describe changes more accurately over time in this GW veteran cohort, we examined cognitive functioning in those with probable Post-Traumatic Stress Disorder (PTSD) versus those without.Participants and Methods:The FDC is the longest running cohort of GW veterans with initial baseline cognitive, mood, exposure and trauma assessments in 1997-1998 and follow-up evaluations in 2019-2022. FDC veterans (N=48) who completed both time points were the participants for this study. Veterans were categorized into dichotomous (yes/no) groups of PTSD classification. The PTSD checklist (PCL) was used to determine PTSD case status. Symptom ratings on the PCL were summed (range:17-85) and a cutoff score of 36 or higher was utilized to indicate probable PTSD. Neuropsychological measures of mood (POMS) and memory (Visual Reproductions from the Weschler Memory Scale-R; California Verbal Learning Test Second Edition; CVLT2) and executive function and language; (Delis-Kaplan Executive Function System- Color Word and Verbal fluency- Animals) were compared overtime using Paired T-tests.Results:The study sample (N=48) was 92% male and 96% reported active-duty status at the time of the GW. Mean current age was 58 years. All veterans reported exposure to at least one war-related toxicant. 48% met criteria for probable PTSD (N = 23) while 52% did not (n=25). No differences between groups were found in any of the POMS subscales, nor were differences seen in verbal memory, executive function, or language tasks. There were, however, significant differences in nonverbal memory in those with probable PTSD showing fewer details recalled during delay on the WMS-R Visual Reproductions (p&lt;0.05).Conclusions:In this longitudinal analysis, GW veterans with PTSD showed declines in nonverbal memory and consistent levels of function in all other tasks. Basic mood scales did not show decline; therefore, these results are not due to generalized changes in mood. All participants reported at least one neurotoxicant exposure and we did not have the power to examine the impact of the individual exposures, thus we cannot rule any contributing factors other than PTSD. This study highlights the importance of longitudinal follow up and continual documentation of GW veterans’ memory performance and their endorsement of mood symptoms overtime. Specifically, these findings reveal that future studies should examine the prolonged course of memory and mood symptomatology in GW veterans who have endorsed a traumatic experience.

9 Exploration of Predictors of Cognitive Flexibility Performance in Long-Term Survivors of Childhood Brain Tumor

Objective:Survivors of childhood brain tumor are historically thought to perform worse on measures of executive functioning, including cognitive flexibility (CF; e.g., set-shifting), when compared to their peers. Commonly utilized measures, such as subtests from the Delis-Kaplan Executive Function System (D-KEFS), have baseline conditions that attempt to measure performances independent of but critical for CF tasks (e.g., motor speed on trail making, letter fluency on verbal fluency). However, in research, conditions measuring CF are often included in analyses without accounting for these important baseline conditions. The aim of the current study is to explore differences in CF performance between survivors and their healthy peers when controlling for baseline conditions. The variance explained by each baseline condition on CF condition performance in survivors is also explored.Participants and Methods:A sample of 107 long-term survivors of childhood brain tumor (Mage=21.81, SD=5.99, 50.5% female) and 142 healthy controls (Mage= 23.25, SD=6.61, 61.3% female) were administered the Trail Making Test (TMT), Color-Word Interference (CWI), and Verbal Fluency (VF) subtests from the D-KEFS. For the TMT, baseline conditions include visually scanning for a target, motor speed, and letter and number sequencing. For the CWI subtest, baseline conditions include rapid color naming, word reading, and reading words in a different colored ink. On the VF subtest, baseline conditions include rapidly naming words with a specific letter and from a specific category. An analysis of covariance was conducted for each subtest to determine if groups differed in performance on the CF condition (i.e., Number-Letter Switching, Inhibition/Switching, Category Switching Accuracy) when controlling for baseline conditions. In survivors only, linear regressions investigated the amount of variance explained by each baseline condition on the CF conditions of each subtest.Results:Groups did not differ in CF performance of each subtest when controlling for baseline conditions (ps&gt;.10). Across subtests, baseline conditions significantly predicted CF performance in survivors. On the TMT, Letter Sequencing (p=.003, unique-R2=.05), but not Visual Scanning, Number Sequencing, or Motor Speed, was a significant predictor of Number-Letter Sequencing performance (p&lt;.001, R2=.50). On the CWI subtest, Word Reading (p&lt;.001, unique-R2=.09) and Inhibition (p&lt;.001, unique-R2=.05), but not Color Naming, were significant predictors of Inhibition/Switching performance (p&lt;.001, R2=.67). On the VF subtest, Letter Fluency (p=.009, unique-R2=.06) and Category Fluency (p&lt;.001, unique-R2=.08) were significant predictors of Category Switching Accuracy performance (p&lt;.001, R2=.37).Conclusions:Findings suggest that CF may not differ between survivors and their healthy peers, but that other factors of executive functioning, such as processing speed, drive performance differences on measures of CF. As these tasks rely heavily on speed, survivors may be slower than their healthy counterparts, but may not perform worse on set-shifting. In addition, these results highlight the importance of controlling for lower-order processes in analyses to help isolate CF performance and more accurately characterize potential differences between groups. While replication of findings in survivors and other clinical groups (e.g., congenital heart disease, traumatic brain injury) is still needed, this work can help inform which processes are most important to account for, which is not yet established.

50 Neuropsychological Functioning in Depression, Borderline Personality Disorder, and Suicidality

Objective:Depression and borderline personality disorder (BPD) are frequently comorbid psychiatric disorders that reliably share deficits in executive functioning (EF). In addition to EF, meta-analytic evidence indicates that processing speed and verbal memory are also affected in depression and BPD, but the impact of BPD further spans the domains of attention, nonverbal memory, and visuospatial abilities. Suicidality is a notable phenotypic commonality in depression and BPD. Neuropsychologically, there are consistent discrepancies between individuals who have and have not thought about suicide in global cognitive functioning, as well as between those who have attempted suicide and those who have just thought about suicide in EF. This study aims to replicate the effect size differences between these groups and explore whether neuropsychological functioning relates to dimensional measures of psychopathology.Participants and Methods:Right-handed women between the ages of 18 and 55 were recruited into one of three diagnostic groups: a) current major depressive episode (MDD; n=22); b) current major depressive episode with comorbid BPD (MDD+BPD; n=19); and c) absence of current major depressive episode and BPD (controls; n=20). Groups were also classified based on historical suicide attempt and on the presence or absence of historical suicidal ideation. Exclusions included bipolar disorder, neurodevelopmental disorder, moderate/severe brain injury, neurological illness, serious physical illness, eating disorder, and moderate/severe alcohol/substance use disorder. Participants were administered the Zanarini Rating Scale for Borderline Personality Disorder (ZAN-BPD), Beck Depression Inventory (BDI-II), Interpersonal Needs Questionnaire (INQ), UPPS-P Impulsive Behavior Scale, Everyday Memory Questionnaire, Brief Visuospatial Memory Test (BVMT), California Verbal Learning Test (CVLT), Delis-Kaplan Executive Function System (D-KEFS) Color-Word Interference Test, D-KEFS Trail Making Test, D-KEFS Verbal Fluency, Wechsler Adult Intelligence Scale-IV Coding and Digit Span subtests, Wechsler Memory Scale-IV Logical Memory, and Wechsler Test of Adult Reading.Results:With one exception, analyses of raw scores indicated there were no significant neuropsychological differences between groups based on diagnosis, historical suicidal ideation, and suicide attempt (p&gt;.05). However, individuals with MDD+BPD, historical suicidal ideation, or suicide attempt endorsed more memory complaints than the other groups with large effect size differences. Differences in self-reported impulsivity indicated large effects between controls and MDD+BPD, moderate to large effects when comparing controls to MDD and MDD to MDD+BPD, and moderate effects among the suicidal ideation and suicide attempt groups. Impulsivity was rated highest in those with MDD+BPD, historical suicidal ideation, or suicide attempt. These analyses applied false-discovery rate correction and adjusted for age. Using ridge regressions to separately predict depressive symptoms, BPD symptoms, and suicide risk factors, neuropsychological indices were most associated with suicide risk factors and explained 22.8% of INQ variance. Conversely, these indices explained 9.6% of ZAN-BPD variance and 0.6% of BDI-II variance.Conclusions:The neuropsychological literature on BPD describes moderate crosscutting neuropsychological dysfunction, and clarifying the distinct cognitive alterations associated with comorbid psychiatric disorders and suicide phenomena offers novel avenues of research for investigating their mechanisms. While neuropsychological functioning may not strongly relate to psychiatric symptomatology, it may contribute to meaningful algorithms of suicide risk in individuals with depression and BPD.

78 Utility of the D-KEFS Color Word Interference Test as a Measure of Performance Validity in Adults Referred for a Psychoeducational Evaluation

Objective:Previous investigations have demonstrated the clinical utility of the Delis-Kaplan Executive Function System (D-KEFS) Color Word Interference Test (CWIT) as an embedded validity indicator in mixed clinical samples and traumatic brain injury. The present study sought to cross-validate previously identified indicators and cutoffs in a sample of adults referred for psychoeducational testing.Participants and Methods:Archival data from 267 students and community members self-referred for a psychoeducational evaluation at a university clinic in the South were analyzed. Referrals included assessment for attention-deficit hyperactivity disorder, specific learning disorder, autism spectrum disorder, or other disorders (e.g., anxiety, depression). Individuals were administered subtests of the D-KEFS including the CWIT and several standalone and embedded performance validity indicators as part of the evaluation. Criterion measures included The b Test, Victoria Symptom Validity Test, Medical Symptom Validity Test, Dot Counting Test, and Reliable Digit Span. Individuals who failed 0 criterion measures were included in the credible group (n = 164) and individuals failing 2 or more criterion measures were included in the non-credible group (n = 31). Because a subset of the sample were seeking external incentives (e.g., accommodations), individuals who failed only 1 of the criterion measures were excluded (n = 72). Indicators of interest included all test conditions examined separately, the inverted Stroop index (i.e., better performance on the interference trial than the word reading or color naming trials), inhibition and inhibition/switching composite, and sum of all conditions.Results:Receiver Operating Characteristics (ROC) curves were significant for all four conditions (p &lt; .001) and the inverted stroop index (p = .032). However, only conditions 2, 3 and 4 met minimal acceptable classification accuracy (AUC = .72 - 81). ROC curves with composite indicators were also significant (p &lt; .001), with all three composite indicators meeting minimal acceptable classification accuracy (AUC = .71- .80). At the previously identified cutoff of age corrected scale score of 6 for all four conditions, specificity was high (.88 -.91), with varying sensitivity (.23 - .45). At the previously identified cutoff of .75 for the inverted stroop index, specificity was high (.87) while sensitivity was low (.19). Composite indicators yielded high specificity (.88 - .99) at previously established cutoffs with sensitivity varying from low to moderate (.19 - .48). Increasing the cutoffs (i.e., requiring higher age corrected scale score to pass) for composite indicators increased sensitivity while still maintaining high specificity. For example, increasing the total score cutoff from 18 to 28 resulted in moderate sensitivity (.26 vs .52) with specificity of .91.Conclusions:While a cutoff of 6 resulted in high specificity for most conditions, the sum of all four conditions exhibited the strongest classification accuracy and appears to be the most robust indicator which is consistent with previous research (Eglit et al., 2019). However, a cutoff of 28 as opposed to 18 may be most appropriate for psychoeducational samples. Overall, the results suggest that the D-KEFS CWIT can function as a measure of performance validity in addition to a measure of processing speed/executive functioning.

3 Optimizing Cognitive Rehabilitation of the Injured Warfighter

Objective:Many individuals who experienced a mild traumatic brain injury (mTBI) have persistent cognitive complaints. Traditional cognitive rehabilitation (TCR) interventions were primarily developed for severe neurological injury which has limited effectiveness in rehabilitation of active duty military personnel who have the goal of returning to full military operational status. To remain on active duty, warfighters must have sufficient mental competency to safely and effectively function in complex environments such as combat. There is need for a cognitive rehabilitation approach that addresses demands of military personnel to expedite return to duty. The Strategic Memory Advanced Reasoning Training (SMART) program is novel alternative to TCR. SMART is an evidence-based advanced reasoning protocol that enhances cognitive domains essential to military readiness (e.g., mental agility, strategic learning, problem solving, and focus) and requires less than half of the treatment time. The objective of this study was to assess the efficacy of SMART compared to TCR in terms of overall recovery as well as change in specific cognitive domains.Participants and Methods:Participants were recruited from a military treatment facility. All patients had at least one diagnosed mTBI as well as persistent cognitive complaints. Participants completed the Rey-15 to ensure performance validity. Final sample was SMART n = 28 and SCORE n = 19. Primary dependent measure was the Global Deficit Scale (GDS). GDS was calculated from: Hopkins Verbal Learning Test-Revised (HVLT-R); Delis Kaplan Executive Functioning System Color Word (CW) and Trail Making (TM), Paced Auditory Serial Addition Test (PASAT), and the Symbol Digit Modality Test (SDMT). Demographically corrected t-scores were converted to deficit scores as follows: &gt;40 = 0, 35-39 = 1, 30-34 = 2, 25-29 = 3, 20-24 = 4, &lt;20 = 5. Deficit scores were averaged to calculate GDS. For each measure, Hohen’s g was analyzed for effect size comparisons pre-post treatment.Results:Average number of treatment hours was significantly lower in the SMART condition (SMART: M = 18.47 hours, SD = 2.17; TCR: M = 42.42 hours, SD = 3.79, p &lt;.001). A repeated measures ANOVA showed a significant change on GDS post-treatment (F = 30.25, p &lt; .001) with a large effect size (n2 = .402); however, the interventions did not differ on GDS change. Impact on cognitive domains was relatively equivalent for processing speed (SMART h = 0.67 vs TCR h = -.54) and executive function (SMART h = -0.92 vs TCR h = -.85); however, SMART had a larger impact on memory (SMART h = -0.81 vs TCR h = -.39). SMART resulted in large improvements in retention and recognition memory which were minimally impacted by TCR.Conclusions:Both TCR and SMART had comparable effectiveness in improving cognitive impairment, though SMART was completed in less than half of the treatment time. Both interventions had large effect sizes on processing speed and executive functioning; however, SMART was more effective in improving long-term memory. Memory is an integral part of military readiness. Further investigation is required to determine the relative effectiveness of these two approaches to improving cognitive readiness of the warfighter.