It's about time: mitigating cancer-related cognitive impairments through findings from computational models of the Wisconsin Card Sorting Task.

BACKGROUND: Many cancer survivors experience cancer-related cognitive impairment (CRCI), often with significant negative consequences across various life domains. Emerging evidence suggests that allowing additional time to process information before acting may be a useful strategy for those with CRCI to mitigate some of its impacts. The Wisconsin Card Sorting Task (WCST), a measure of general cognition, has shown that for some cancer survivors, longer task completion time facilitates similar task performance outcomes to control populations concerning perseveration errors; a key performance metric of the WCST. However, assessing if this strategy may be useful, as well as determining for whom it may be useful, with regard to strengths and weaknesses among select cognitive domains, is challenging due to factors such as the problem of task impurity. Accordingly, this study provides an initial computational and experimental assessment of whether additional time to process information before acting is a useful strategy for those with CRCI. METHODS: We simulated individual cognitive differences observed in humans by varying contributions of executive functioning components (updating, shifting, inhibition) to yield 48 distinct computational models of the WCST. Our main manipulation was then to provide these models with more or less time (at three levels of 20, 40 and 60 cycles) before models executed an action to sort a given card. We compared the number of perseveration errors on the WCST produced by the computational models. Additionally, we determined models that simulated the performance of cancer survivors on the WCST by comparing the number of perseveration errors produced by the models to human data. RESULTS: Additional processing time resulted in the models producing significantly fewer perseveration errors, supporting our hypothesis. In addition, 8 unique models simulated the performance of cancer survivors on the WCST. Additional time appeared to have a positive influence on performance primarily by mitigating the impacts of severe inhibition impairments. For more severe global executive function impairments, a substantial amount of additional time was required to mitigate the impacts of the impairments. For the most severe impairments, additional time was unable to adequately mitigate the impact on performance. CONCLUSION: Additional processing time may be a useful strategy to rectify perseveration errors among cancer survivors with CRCI. Our findings have implications for the development of practical strategies, such as workload and deadline management in occupational settings, which may mitigate the negative effects of CRCI.

Heroin use and neuropsychological impairments: comparison of intravenous and inhalational use.

BACKGROUND AND OBJECTIVES: Injection and inhalational heroin use are associated with different levels of brain exposure to heroin and its metabolites and differences in the severity of dependence, which might lead to differential impacts on neuropsychological functions. We examined the difference and the magnitude of difference in the neuropsychological functions between inhalational and injection heroin-dependent subjects and also compared them with healthy controls. METHODS: The study sample comprised three groups: 73 subjects with injection heroin dependence, 74 with inhalational heroin dependence, and 75 healthy controls (HC). We excluded patients with HIV, head injury, epilepsy, and severe mental illness. Neuropsychological assessments were done by Standard Progressive Matrices, Wisconsin Card Sorting Test (WCST), Iowa Gambling Task, Trail-Making Tests A and B (TMT), and Verbal and Visual Memory 1 and 2 Backtests (NBT). We estimated independent effects of the groups on various neuropsychological test parameters, adjusted for age and duration of dependence. RESULTS: In the WCST, the inhalational heroin-dependent group took more trials to complete the first category and had higher scores in the failure to maintain set than controls. The intravenous group had higher total errors than controls in verbal working memory tests and Visual Working Memory 2 Backtest. This group scored higher commission errors in the Verbal 2 Backtest than the controls. The two groups of heroin users differed in failure to maintain set and Verbal Working Memory 2 Backtests. The effect sizes of the group differences were modest. CONCLUSION AND SCIENTIFIC SIGNIFICANCE: Either route of heroin use is associated with cognitive impairments; inhalational and injection use involve different cognitive domains.

Executive functions in Parkinson's disease / Funções executivas na doença de Parkinson / Funciones ejecutivas en la enfermedad de Parkinson

The objective of this study was to investigate executive functions (EFs) in older adults with Parkinson's disease (PD). It was a cross-sectional and comparative study, composed of 62 participants divided into PD group (n = 31; M age = 75.26; SD age = 7.26) and control group (n = 31; M age = 74.03; SD age = 6.95), aged 61 to 93 years, recruited for convenience in 5 cities in the state of Rio Grande do Sul. The instruments used were a sociodemographic data questionnaire; MMSE; GDS-15; BIS-11; verbal fluency tasks (FAS and animals), DEX; WCST-64 and FDT. Descriptive analyzes and Student's t and Chi-square tests were used. The PD group had a lower performance in the WCST-64 and FDT tests compared to controls, indicating worse performance in tasks that required reasoning, cognitive flexibility and processing speed, in addition, showed difficulties in performing tasks that require EF (DEX). (AU)

O objetivo foi investigar as funções executivas (FE) em idosos com Doença de Parkinson (DP). Estudo transversal e comparativo, composto por 62 participantes, 50% do sexo feminino, recrutados por conveniência em cinco cidades do estado do Rio Grande do Sul, e divididos em dois grupos: com DP (n = 31; Midade = 75,26; DP idade = 7,26) e grupo controle (n = 31; M idade = 74,03; DP idade = 6,95), com idade entre 61 e 93 anos. Os instrumentos utilizados foram: questionário de dados sociodemográficos, MEEM; GDS-15; BIS-11; tarefas de fluência verbal (FAS e animais); DEX; WCST-64 e FDT. Foram utilizadas análises descritivas e os testes t de Student e Qui-quadrado. O grupo com DP teve desempenho inferior nos testes WCST-64 e FDT em comparação aos controles, indicando pior desempenho nas tarefas que exigiam raciocínio, flexibilidade cognitiva e velocidade de processamento, além disso, mostraram dificuldades ao realizar tarefas que demandam FE (DEX). (AU)

El objetivo de este trabajo fue investigar las funciones ejecutivas (FE) en ancianos con enfermedad de Parkinson (EP). Se trató de un estudio transversal y comparativo, compuesto por 62 participantes, 50% mujeres, reclutados por conveniencia en cinco ciudades de la provincia de Rio Grande do Sul, y divididos en dos grupos: con EP (n = 31; M edad = 75,26; DS edad = 7,26) y grupo control (n = 31; M edad = 74,03; DS edad = 6,95). Fueron usados cuestionarios de datos sociodemográficos, MEEM, GDS-15; BIS-11; tareas de fluencia verbal (FAS y animales), DEX; WCST-64 y FDT. Se realizaron análisis descriptivos, prueba t de Student y chi-cuadrado. El grupo EP tuvo un rendimiento más bajo en las pruebas WCST-64 y FDT en comparación con el grupo control, lo que indica un peor rendimiento en tareas que requerían razonamiento, flexibilidad cognitiva y velocidad de procesamiento, además, mostró dificultades para realizar tareas que demandan FE (DEX). (AU)

Neuropsychological and educational profile of children with dyscalculia and dyslexia: a comparative study / Perfil neuropsicológico e escolar de crianças com discalculia e dislexia: estudo comparativo / Perfil neuropsicológico y educativo de los niños con discalculia y dislexia: estudio comparativo

This paper aims to compare the neuropsychological and educational profiles of Brazilian children with dyscalculia (n = 8), dyslexia (n = 13) and without learning disabilities (n = 12). The neuropsychological profile was composed of: (a) intelligence - assessed by the Wechsler Intelligence Scale for Children (WISC-III); (b) attention - WISC-III Coding and Symbol Search subtests; (c) executive functions - Digit Span (backward order) and WISC-III Arithmetic subtests, Pseudoword Repetition Test for Brazilian Children, Stroop Test and Wisconsin Card Sorting Test; (d) memory - WISC-III Digit Span subtest (forward order) and Rey Complex Figures. The educational profile was composed of reading, writing and mathematics, assessed by the Academic Performance Test and the Arithmetic Test. It was found that the groups with dyscalculia and dyslexia did not differentiate in any of the neuropsychological abilities, only in the reading and writing abilities. Neuropsychological variables that could explain these results were discussed. (AU)

Objetivou-se comparar os perfis neuropsicológico e escolar de crianças brasileiras com discalculia (n = 8), dislexia (n = 13) e sem dificuldades escolares (n = 12). O perfil neuropsicológico foi composto por: (a) inteligência: avaliada pela Escala de Inteligência Wechsler para Crianças (WISC-III); (b) atenção: subtestes Códigos e Procurar Símbolos da WISC-III; (c) funções executivas: subtestes Dígitos (ordem inversa) e Aritmética da WISC-III, Teste de Repetição de Pseudopalavras para Crianças Brasileiras, Teste de Stroop e Teste Wisconsin de Classificação de Cartas; (d) memória: subteste Dígitos (ordem direta) da WISC-III e Figuras Complexas de Rey. O perfil escolar foi composto por leitura, escrita e matemática, avaliado pelo Teste de Desempenho Escolar e pela Prova de Aritmética. Verificou-se que os grupos com discalculia e com dislexia não se diferenciaram em nenhuma das habilidades neuropsicológicas, somente nas habilidades escolares de leitura e escrita. Variáveis neuropsicológicas que pudessem explicar esses desempenhos intergrupos foram discutidas. (AU)

El objetivo de este trabajo fue comparar los perfiles neuropsicológicos y escolares de niños brasileños con Discalculia (n = 8), Dislexia (n = 13) y niños sin dificultades escolares (n = 12). El perfil neuropsicológico fue compuesto por: (a) inteligencia: evaluada por Escala de Inteligencia Wechsler para Niños (WISC-III); (b) atención: subtests Códigos y Búsqueda de Símbolos de la WISC-III; (c) funciones ejecutivas: subtests Dígitos (orden inverso) y Aritmética de la WISC-III, Test de Repetición de Pseudopalabras para Niños Brasileños, Test de Stroop y Test Wisconsin de Clasificación de Cartas; (d) memoria: subtest Dígitos (orden directo) de la WISC-III y Figuras Complejas de Rey. El perfil escolar fue compuesto por lectura, escritura y matemática, evaluado por el Test de Desempeño Escolar y por la Prueba de Aritmética. Se verificó que los grupos con Discalculia y con Dislexia no se diferenciaron en ninguna de las habilidades neuropsicológicas, sólo en las habilidades escolares de lectura y escritura. Fueron discutidas variables neuropsicológicas que pueden explicar esos desempeños intergrupales. (AU)

Effects of HIV on executive function and verbal fluency in Cameroon.

HIV-associated neurocognitive disorders (HAND) are frequently associated with impaired executive function and verbal fluency. Given limited knowledge concerning HAND in Sub-Saharan-Africa and lack of Cameroonian adult neuropsychological (NP) test norms, we administered four executive function [Halstead Category Test (HCT), Wisconsin Card Sorting Test (WCST), Color Trails-II (CTT2), and Stroop Color-Word-Interference (SCWT)] and three verbal fluency (Category, Action, and Letter Fluency) tests to 742 adult Cameroonians (395 HIV-, 347 HIV+). We developed demographically-corrected NP test norms and examined the effects of HIV and related variables on subjects' executive function and verbal fluency. HIV+ subjects had significantly lower T-scores on CTT2 (P = 0.005), HCT (P = 0.032), WCST (P < 0.001); lower executive function composite (P = 0.002) and Action Fluency (P = 0.03) T-scores. ART, viremia, and CD4 counts did not affect T-scores. Compared to cases harboring other viral subtypes, subjects harboring HIV-1 CRF02_AG had marginally higher CTT2 T-scores, significantly higher SCWT (P = 0.015) and executive function (P = 0.018) T-scores. Thus, HIV-1 infection in Cameroon is associated with impaired executive function and some aspects of verbal fluency, and viral genotype influenced executive function. We report the first normative data for assessing executive function and verbal fluency in adult Cameroonians and provide regression-based formulas for computing demographically-adjusted T-scores. These norms will be useful for investigating HIV/AIDS and other diseases affecting cognitive functioning in Cameroon.

Genome-wide association study of cognitive flexibility assessed by the Wisconsin Card Sorting Test.

Cognitive flexibility is a critical component of executive function and is strongly influenced by genetic factors. We conducted a genome-wide association study of cognitive flexibility (as measured by perseverative errors on the Wisconsin Card Sorting Test) in two sets of African American (AA) and European American (EA) subjects (Yale-Penn-1: 1,411 AAs/949 EAs; Yale-Penn-2: 1,178 AAs/1,335 EAs). We examined the association of cognitive flexibility with genotyped or imputed SNPs across the genome. In AAs, two correlated common single nucleotide polymorphisms (SNPs) (rs7165213/rs35633795) in the downstream region of the noncoding gene LOC101927286 on chromosome 15 showed genome-wide significant (GWS) associations with cognitive flexibility (Yale-Penn-1: p = 6.0 × 10-9 /1.3 × 10-8 ; Yale-Penn-2: p = .029/.010; meta-analysis: p = 4.2 × 10-7 /1.0 × 10-7 ) in the same effect direction. In EAs, no GWS associations were observed. Enriched gene sets identified by Data-driven Expression-Prioritized Integration for Complex Traits (DEPICT) analysis of the top SNPs (pmeta-analysis < 10-5 ) included the signalosome and ubiquitin-specific peptidase 9, X-linked (USP9X) subnetwork in AAs, and abnormal frontal and occipital bone morphology in EAs. We also performed polygenic risk score (PRS) analysis to examine the genetic correlation of cognition-proxy phenotypes (general cognitive function, education attainment, childhood intelligence, and infant head circumference) and cognitive flexibility in EAs. The PRS derived from general cognitive function-associated SNPs was significantly associated with cognitive flexibility. Nongenetic factors (age, education, sex, and tobacco recency) also exerted significant effects on cognitive flexibility. Our study demonstrates that both genetic and nongenetic factors impact cognitive flexibility, and variants in genes involved in protein degradation and brain development may contribute to population variation in cognitive function.

Diversities of behavioral traits and neuropsychological function in different substance addiction.

OBJECTIVE: There are various temperaments and personality characters that modulate the development of substance addiction. The pharmacological properties of substances would alter the homeostasis of brain function and influence the neuropsychological performance through different neurotransmissions which then facilitate diverse emotional and behavioral responses. Our goal is to assess the interaction between personality characteristics, neuropsychological performances and Stroop interference in alcoholics, heroin and amphetamine dependent persons. METHODS: Subjects with alcohol (N=95), heroin (N=82) and amphetamine (N=57) dependence were recruited. Diagnostic interview and questionnaires evaluating the psychiatric symptoms were done, followed by neuropsychological assessments of Stroop and Wisconsin card sorting tests (WCST). Differences between the study groups were analyzed by one-way ANOVA with Scheffe's test. RESULTS: The individuals with alcohol dependence had significantly higher scores of neurotic, dysphoric and impulsive traits (P<0.001) than heroin and amphetamine dependent groups. In Stroop tests, the alcohol dependent subjects also showed delayed response on incongruent naming interferences compared to both of heroin and amphetamine groups (P<0.001). Perseverative errors and responses of WCST were significantly higher in heroin than in alcoholic dependent persons (P<0.01). CONCLUSIONS: Individuals with different substance dependence have distinct behavioral traits for developing addicted behaviors and had variant deficits of neuropsychological function.

Influencia de la memoria de trabajo y la flexibilidad cognitiva en la ejecución de la tarea balloon analogue risk task / Influence of Working Memory and Cognitive Flexibility in Performance of the Balloon Analogue Risk task

Diversos estudios plantean la importancia que tienen las funciones ejecutivas como la flexibilidad cognitiva, la inhibición y la memoria de trabajo en la toma de decisiones. En este estudio se pretende valorar si la memoria de trabajo y la flexibilidad cognitiva, procesos cognitivos presentes en la toma de decisiones, pueden explicar las alteraciones en el rendimiento de los pacientes con daño cerebral adquirido (DCA) en la Balloon Analogue Risk Task (BART). A 73 pacientes con DCA se les administró la BART, el Trail Making Test (TMTB) y el Wisconsin Card Sorting Test (WCST), para valorar la flexibilidad cognitiva; y el subtest Letras y Números (LN) del WAIS-III para evaluar la memoria de trabajo. Los mismos test fueron administrados a un grupo control de 30 sujetos sin DCA. En el grupo clínico, las variables neuropsicológicas estudiadas incluidas para explicar la variación del BART$ fueron TMTB, p < .001, y WCST, p <.001. Observamos que únicamente la flexibilidad cognitiva valorada con WCST y TMTB pudo explicar las alteraciones en el rendimiento de los pacientes con DCA en la BART. Por tanto, es lógico pensar que si el rendimiento de la BART depende de la flexibilidad cognitiva de estos pacientes, entonces es de esperar que dicha capacidad sea un buen factor predictivo en la toma de decisiones.

A number of studies have raised the importance of certain executive functions such as attention, cognitive flexibility, response inhibition, and working memory in decision-making. The purpose of this study is to prove whether or not working memory and cognitive flexibility, capacities present in decision-making, can explain the changes in the performance of patients with acquired brain damage in Balloon Analogue Risk Task (BART). 73 patients with adult Acquired Brain Injury (ABI) were assessed with the BART, Trail Making Test B (TMTB), Wisconsin Card Sorting Test (WCST) to asses cognitive flexibility; and subtest Letter-Number (LN) of WAIS -III to asses working memory. The same test was administered to a control group of 30 subjects without ABI. In the clinical group, the only variables studied that were included to explain the variation in BART$ were TMTB, p < .001, and WCST, p < .001. We observe that changes in the performance of our patients with ABD in BART could only be explained by cognitive flexibility. Therefore we can conclude that performance in BART depends on the cognitive flexibility of these patients; therefore, it is to be expected that this capacity will be a good predictor of decision-making.