Screening executive function and global cognition with the Nine-Card Sorting Test: healthy participant studies and ageing implications

Neurocognitive factorial structure of executive functions: Evidence from neurotypicals and frontotemporal dementia

The latent structure of executive functions (EFs) remains controversial. Confirmatory factorial analysis (CFA) has provided support for both multidimensional (assumes EFs to be functionally separable but related components) and bifactor (proposes all components are nested within a common factor) models. However, these CFA models have never been compared in patient samples, nor regarding their neuroanatomical correlates. Here, we systematically contrast both approaches in neurotypicals and in a neurodegenerative lesion model (patients with the behavioral variant frontotemporal dementia, bvFTD), characterized by executive deficits associated with frontal neurodegeneration. First, CFA was used to test the models' fit in a sample of 341 neurotypicals and 29 bvFTD patients based on performance in an executive frontal screening battery which assesses working memory, motor inhibition, verbal inhibition, and abstraction capacity. Second, we compared EFs factor and observed scores between patients and matched controls. Finally, we used voxel-based morphometry (VBM) to compare the grey matter correlates of factor and observed scores. CFA results showed that both models fit the data well. The multidimensional model, however, was more sensitive than the bifactor model and the observed scores to detect EFs impairments in bvFTD patients. VBM results for the multidimensional model revealed common and unique grey matter correlates for EFs components across prefrontal-insular, posterior, and temporal cortices. Regarding the bifactor model, only the common factor was associated with prefrontal-insular hubs. Observed scores presented scant, non-frontal grey matter associations. Converging behavioral and neuroanatomical evidence from healthy populations and a neurodegenerative model of EFs supports an underlying multidimensional structure.

Age Differences in the Subcomponents of Executive Functioning

OBJECTIVES

Across the life span, deficits in executive functioning (EF) are associated with poor behavioral control and failure to achieve goals. Though EF is often discussed as one broad construct, a prominent model of EF suggests that it is composed of three subdomains: inhibition, set shifting, and updating. These subdomains are seen in both younger (YA) and older adults (OA), with performance deficits across subdomains in OA. Therefore, our goal was to investigate whether subdomains of EF might be differentially affected by age, and how these differences may relate to broader global age differences in EF.

METHODS

To assess these age differences, we conducted a meta-analysis at multiple levels, including task level, subdomain level, and of global EF. Based on previous work, we hypothesized that there would be overall differences in EF in OA.

RESULTS

Using 1,268 effect sizes from 401 articles, we found overall differences in EF with age. Results suggested that differences in performance are not uniform, such that variability in age effects emerged at the task level, and updating was not as affected by age as other subdomains.

DISCUSSION

These findings advance our understanding of age differences in EF, and stand to inform early detection of EF decline.

Remembering a name: Neuropsychological validity studies and a computer proposal for detection of anomia

There are contradictory results or lack of validity studies concerning the naming function and brain laterality. Although anomia is a frequent symptom of memory impairment, and the most relevant symptom of aphasia, few studies have been conducted to evaluate its validity for detecting patients with left-hemisphere damage (LD), as per the MeSH definition.

Age, education and gender effects on Wisconsin card sorting test: standardization, reliability and validity in healthy Argentinian adults

The Wisconsin Card Sorting Test (WCST) is a widely used neuropsychological assessment of executive functioning. The aim of this study was to provide norm values and analyze the psychometric properties of WCST in healthy Argentinian adults aged from 18 to 89 years old (N = 235). Descriptive statistics are reported as means, standard deviations and percentiles, with the effects of age, education and gender being investigated by ANOVA, and with the effect sizes being calculated. The psychometrics were studied using the WCST structure, reliability, convergent validity, and discriminant validity, and WCST norms adjusted for age and educational level are proposed. This instrument is a reliable and valid tool for the assessment of executive functions. However, as the age- and educational-related effects were demonstrated, these characteristics need to be considered before interpreting WCST scores. Regarding gender, no differences were found. Our results expand the geographical and sociocultural applicability of WCST.

Validity and features of spontaneous speech in acute aphasia as evaluated with the Brief Aphasia Evaluation: is fluent aphasia more severe than nonfluent aphasia?

PURPOSE

To explore the relationship between the two components of spontaneous speech in the Brief Aphasia Evaluation (BAE) and the rest of the scale represented by its three main factors: The Expression, Comprehension, and Complementary factors.

METHODS

BAE has proven validity and reliability. The evaluation of spontaneous speech in this scale comprises two components: Performance Rank (score: 0-3) and Type of Disorder (Fluency [F], Content [C], or Mixed [FC]) when rank < 3. Sixty-seven patients with left brain damage and 30 demographically matched healthy participants (HP) were studied. It was analyzed the correlation between Performance Rank and the three BAE factors and, recoding 3 as 0 and < 3 as 1, the sensitivity/specificity of this component for each factor. The effect of Type of Disorder on the three factors was analyzed.

RESULTS

1) Performance Rank: Correlations of 0.84 (Expression), 0.81 (Comprehension), and 0.76 (Complementary) were observed, with a sensitivity and specificity ≥ 78% for any factor; 2) Type of Disorder: The performance significantly decreased from FC to C and from C to F in Expression (FC < C < F), from FC to C and from FC to F also in Comprehension and Complementary, from patients with any type of disorder to HP.

CONCLUSION

Performance Rank was a relevant indicator of aphasia by its consistency with valid and comprehensive dimensions of acute language impairments. A degree difference between F and C was observed, being F a milder disorder; i.e., fluency problems were less severe than retrieval or anomia ones.

Relationship between the caregiver's report on the patient's spontaneous-speech and the Brief Aphasia Evaluation

PURPOSE

To study the relationship between the caregiver's perception about the patient's impairment in spontaneous speech, according to an item of four questions administered by semi-structured interview, and the patient's performance in the Brief Aphasia Evaluation (BAE).

METHODS

102 right-handed patients with focal brain lesions of different types and location were examined. BAE is a valid and reliable instrument to assess aphasia. The caregiver's perception was correlated with the item of spontaneous speech, the total score and the three main factors of the BAE: Expression, Comprehension and Complementary factors. The precision (sensitivity/ specificity) about the caregiver's perception of the patient's spontaneous speech was analyzed with reference to the presence or absence of disorder, according to the professional, on the BAE item of spontaneous speech.

RESULTS

The studied correlation was satisfactory, being greater (higher than 80%) for the following indicators: the item of spontaneous speech, the Expression factor and the total score of the scale; the correlation was a little smaller (higher than 70%) for the Comprehension and Complementary factors. Comparing two cut-off points that evaluated the precision of the caregiver's perception, satisfactory results were observed in terms of sensitivity and specificity (>70%) with likelihood ratios higher than three. By using the median as the cut-off point, more satisfactory diagnostic discriminations were obtained.

CONCLUSION

Interviewing the caregiver specifically on the patient's spontaneous speech, in an abbreviated form, provides relevant information for the aphasia diagnosis.