Advancing the Understanding of the Factor Structure of Executive Functioning

The common factor of executive functions measures nothing but speed of information uptake

There is an ongoing debate about the unity and diversity of executive functions and their relationship with other cognitive abilities such as processing speed, working memory capacity, and intelligence. Specifically, the initially proposed unity and diversity of executive functions is challenged by discussions about (1) the factorial structure of executive functions and (2) unfavorable psychometric properties of measures of executive functions. The present study addressed two methodological limitations of previous work that may explain conflicting results: The inconsistent use of (a) accuracy-based vs. reaction time-based indicators and (b) average performance vs. difference scores. In a sample of 148 participants who completed a battery of executive function tasks, we tried to replicate the three-factor model of the three commonly distinguished executive functions shifting, updating, and inhibition by adopting data-analytical choices of previous work. After addressing the identified methodological limitations using drift-diffusion modeling, we only found one common factor of executive functions that was fully accounted for by individual differences in the speed of information uptake. No variance specific to executive functions remained. Our results suggest that individual differences common to all executive function tasks measure nothing more than individual differences in the speed of information uptake. We therefore suggest refraining from using typical executive function tasks to study substantial research questions, as these tasks are not valid for measuring individual differences in executive functions.

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.

Psychometric properties of the Teenage Executive Functioning Inventory (TEXI): A confirmatory factor analysis and measurement invariance by gender in Bangladeshi adolescents

The Teenage Executive Functioning Inventory (TEXI) is a newly developed, reliable, and valid measure to assess deficits in executive functioning. The present study aimed to adapt and evaluate the psychometric properties and factor structure of the Bangla version of the TEXI in a sample of Bangladeshi adolescents. The cross-sectional research on 360 Bangladeshi adolescents aged between 12 and 18 years was carried out. Initially, the 20-item TEXI was translated into Bangla and pretested. Confirmatory factor analysis (CFA) was used to test factor structure and measurement invariance across genders. The CFA identified a two-factor solution, including working memory and inhibition, thereby replicating the original model. Multi-group CFA further suggested configural, metric, scaler, and residual measurement invariance between genders in a Bangladeshi sample. The internal consistency reliability of the TEXI was adequate. Construct and criterion-related validity were confirmed by establishing substantial and statistically significant correlations between the two factors within the TEXI and the associations between academic performance and the overall TEXI score. The Bangla version of the TEXI is a valuable measurement tool for evaluating executive dysfunction among adolescents. This study opens the door to future research on adolescents' executive functioning deficits and their relationship with other real-life behaviors.

Performance on a relational integration task is impaired during hangover

Recently, researchers have proposed an updated model of executive functions that includes relational integration, the mental ability to bind information into more complex structures. Hangover is known to disrupt other core components of executive functions, but little is known about how it influences relational integration. Therefore, this study aimed to investigate how hangover influences performance on a relational integration task. Twenty-seven participants completed an online relational integration task and mood- and emotion-regulation questionnaires during a hangover and no-hangover condition in this naturalistic design study. Results indicated that relational integration was impaired in hangover (p < 0.001, ηp2 = 0.562) relative to the no-hangover condition. In addition, participants experienced greater difficulties in regulating emotions (p < 0.001, d = 0.85) and lower mood (p < 0.001, d = 0.88) during hangover. These results suggest that relational integration is impaired in hangover and add weight to the argument that cognitive impairments in hangover may be due to the hangover-related impact on domain-general processing resources.

The role of working memory updating and capacity in children's mathematical abilities: A developmental cascade model

BACKGROUND

Previous studies indicated that working memory (WM) updating and WM capacity play essential roles in mathematical ability. However, it is unclear whether WM capacity mediates the effect of WM updating on mathematics, and whether the cascading effects vary with different mathematical domains.

AIMS

The current study aims to explore the longitudinal mediating role of WM capacity between WM updating and mathematical performance, and how the relations change with the age and domains.

SAMPLE

A total of 131 Chinese first-graders participated the study.

METHODS

Participants were required to complete tasks on WM updating and WM capacity in Grade 1 and Grade 2, as well as paper-and-pencil tests on mathematics achievement in Grade 3. The role of WM updating and capacity in the development of pupil's mathematical achievement was examined.

RESULTS

Results revealed that verbal WM updating in Grade 1 predicted basic arithmetic and logical-visuospatial ability in Grade 3 via its cascading effect on verbal WM capacity in Grade 2. Moreover, visuospatial WM updating in Grade 1 predicted visuospatial WM capacity in Grade 2. Visuospatial WM capacity in Grade 1 predicted logical-visuospatial ability in Grade 3 instead of basic arithmetic ability in Grade 3.

CONCLUSIONS

The findings suggested that WM updating exerts effect on pupil's mathematical performance via WM capacity, meanwhile, this effect depends on children's mathematics domain.

The structure of executive functions in preschool children and chimpanzees

Executive functions (EF) are a core aspect of cognition. Research with adult humans has produced evidence for unity and diversity in the structure of EF. Studies with preschoolers favour a 1-factor model, in which variation in EF tasks is best explained by a single underlying trait on which all EF tasks load. How EF are structured in nonhuman primates remains unknown. This study starts to fill this gap through a comparative, multi-trait multi-method test battery with preschoolers (N = 185) and chimpanzees (N = 55). The battery aimed at measuring working memory updating, inhibition, and attention shifting with three non-verbal tasks per function. For both species the correlations between tasks were low to moderate and not confined to tasks within the same putative function. Factor analyses produced some evidence for the unity of executive functions in both groups, in that our analyses revealed shared variance. However, we could not conclusively distinguish between 1-, 2- or 3-factor models. We discuss the implications of our findings with respect to the ecological validity of current psychometric research.

On the Relation between the Development of Working Memory Updating and Working Memory Capacity in Preschoolers

This study aims at investigating the relationship between working memory updating and working memory capacity in preschool children. A sample of 176 preschoolers (36–74 months) was administered a working memory updating task (Magic House) along with three working memory capacity tests that specifically measure their core attentional component (M capacity, as defined in the theory of constructive operators): Backward Word Span, Mr. Cucumber, and Direction Following Task. Correlational analyses and cross-classification prediction analyses were performed. Updating and capacity were significantly correlated, although the correlations were not high when age was partialled out. Capacity increased with age, and mediated the relation between age and updating. More importantly, cross-classification prediction analysis revealed that high updating scores with low M capacity, and low updating scores with relatively high M capacity, are possible events; the only combination ruled out was a low updating score with precocious development of M capacity. These facts demonstrate that updating skills in preschoolers depends on M capacity but does not coincide with it. Therefore, in cognitive developmental theories, the constructs of working memory updating and capacity should be distinguished, and on practical grounds, different tests should be used to measure them.

Do Executive Attentional Processes Uniquely or Commonly Explain Psychometric g and Correlations in the Positive Manifold? A Structural Equation Modeling and Network-Analysis Approach to Investigate the Process Overlap Theory

One of the best-established findings in intelligence research is the pattern of positive correlations among various intelligence tests. Although this so-called positive manifold became the conceptual foundation of many theoretical accounts of intelligence, the very nature of it has remained unclear. Only recently, Process Overlap Theory (POT) proposed that the positive manifold originated from overlapping domain-general, executive processes. To test this assumption, the functional relationship between different aspects of executive attention and the positive manifold was investigated by re-analyzing an existing dataset (N = 228). Psychometric reasoning, speed, and memory performance were assessed by a short form of the Berlin Intelligence Structure test. Two aspects of executive attention (sustained and selective attention) and speed of decision making were measured by a continuous performance test, a flanker task, and a Hick task, respectively. Traditional structural equation modeling, representing the positive manifold by a g factor, as well as network analyses, investigating the differential effects of the two aspects of executive attention and speed of decision making on the specific correlations of the positive manifold, suggested that selective attention, sustained attention, and speed of decision making explained the common but not the unique portions of the positive manifold. Thus, we failed to provide evidence for POT's assumption that the positive manifold is the result of overlapping domain-general processes. This does not mean that domain-general processes other than those investigated here will not be able to show the pattern of results predicted by POT.