Individual differences in speed of mental processing and human cognitive abilities: Toward a taxonomic model

Neurocognitive Profiles of Early Adulthood Attention-Deficit/Hyperactivity Disorder

Objectives

This study examined the neurocognitive profiles of early adulthood attention-deficit/hyperactivity disorder (ADHD) patients using the Korean version of the Wechsler Adult Intelligence Scale, 4th Edition (K-WAIS-IV) and Continuous Performance Test 3rd Edition (CPT-3) assessment results.

Methods

A total of 105 individuals underwent the K-WAIS-IV assessment, and 68 participants completed the CPT-3. We examined the differences between intelligence subindex scores using paired t-tests and applied Pearson's correlation analysis to determine the correlation between the K-WAIS-IV and CPT-3 scores.

Results

Working Memory Index scores were significantly lower than Verbal Comprehension Index scores, whereas Processing Speed Index (PSI) scores were significantly lower than all three other subindex scores. Significant negative correlations were found between all four K-WAIS-IV subindex scores and the CPT-3 scores for Detectability, Omissions, Commissions, Perseverations, Hit Reaction Time, Hit Reaction Time Standard Deviation, and Variability.

Conclusion

The PSI of the K-WAIS-IV can be considered a useful predictor in early adulthood ADHD patients combined with the CPT-3 examination.

Individual differences in attention control: A meta-analysis and re-analysis of latent variable studies

A meta-analysis and re-analysis of prior latent variable studies was conducted in order to assess whether there is evidence for individual differences in broad attention control abilities. Data from 90 independent samples and over 23,000 participants suggested that most (84.4%) prior studies find evidence for a coherent attention control factor with average factor loadings of .51. This latent attention control factor was related to other cognitive ability factors including working memory, shifting, fluid intelligence, long-term memory, reading comprehension, and processing speed, as well as to self-reports of task-unrelated thoughts and task specific motivation. Further re-analyses and meta-analyses suggest that the results remained largely unchanged when considering various possible measurement issues. Examining the factor structure of attention control suggested evidence for sub-components of attention control (restraining, constraining and sustaining attention) which could be accounted for a by a higher-order factor. Additional re-analyses suggested that attention control represents a broad ability within models of cognitive abilities. Overall, these results provide evidence for attention control abilities as an important individual differences construct.

Should Intelligence Tests Be Speeded or Unspeeded? A Brief Review of the Effects of Time Pressure on Response Processes and an Experimental Study with Raven's Matrices

Intelligence tests are often performed under time constraints for practical reasons, but the effects of time pressure on reasoning performance are poorly understood. The first part of this work provides a brief review of major expected effects of time pressure, which includes forcing participants to skip items, convoking a mental speed factor, constraining response times, qualitatively altering cognitive processing, affecting anxiety and motivation, and interacting with individual differences. The second part presents data collected with Raven's matrices under three conditions of speededness to provide further insight into the complex effects of time pressure, with three major findings. First, even mild time pressure (with enough time available for all participants to complete the task at a leisurely pace) induced speeding throughout the whole task, starting with the very first item, and participants sped up more than was actually required. Second, time pressure came with lower confidence and poorer strategy use and a substantial decrease of accuracy (d = 0.35), even when controlling for response time at the item level-indicating a detrimental effect on cognitive processing beyond speeding. Third, time pressure disproportionately reduced response times for difficult items and participants with high ability, working memory capacity, or need for cognition, although this did not differentially affect ability estimates. Overall, both the review and empirical sections show that the effects of time pressure go well beyond forcing participants to speed or skip the last few items and make even mild time constraints inadvisable when attempting to measure maximal performance, especially for high-performing samples.

Causal influences of salience/cerebellar networks on dorsal attention network subserved age-related cognitive slowing

Age-related cognitive slowing is a prominent precursor of cognitive decline. Functional neuroimaging studies found that cognitive processing speed is associated with activation and coupling among frontal, parietal and cerebellar brain networks. However, how the reciprocal influences of inter- and intra-network coupling mediate age-related decline in processing speed remains insufficiently studied. This study examined how inter- and intra-brain network influences mediate age-related slowing. We were interested in the fronto-insular salience network (SN), frontoparietal dorsal attention network (DAN), cerebellar network (CN) and default mode network (DMN). Reaction time (RT) and functional MRI data from 84 participants (aged 18-75) were collected while they were performing the Arrow Task in visual or audial forms. At the subject level, effective connectivities (ECs) were estimated with regression dynamic causal modelling. At the group level, structural equation models (SEMs) were used to model latent speed based on age and the EC mediators. Age was associated with decreased speed and increased inter-network effective connectivity. The CN exerting influence on the DAN (CN → DAN EC) mediated, while the SN → DAN EC suppressed age-related slowing. The DMN and intra-network ECs did not seem to play significant roles in slowing due to ageing. Inter-network connectivity from the CN and SN to the DAN contributes to age-related slowing. The seemingly antagonizing influences of the CN and SN indicate that increased task-related automaticity and decreased effortful control on top-down attention would promote greater speed in older individuals.

Reflections and New Perspectives on Face Cognition as a Specific Socio-Cognitive Ability

The study of socio-cognitive abilities emerged from intelligence research, and their specificity remains controversial until today. In recent years, the psychometric structure of face cognition (FC)-a basic facet of socio-cognitive abilities-was extensively studied. In this review, we summarize and discuss the divergent psychometric structures of FC in easy and difficult tasks. While accuracy in difficult tasks was consistently shown to be face-specific, the evidence for easy tasks was inconsistent. The structure of response speed in easy tasks was mostly-but not always-unitary across object categories, including faces. Here, we compare studies to identify characteristics leading to face specificity in easy tasks. The following pattern emerges: in easy tasks, face specificity is found when modeling speed in a single task; however, when modeling speed across multiple, different easy tasks, only a unitary factor structure is reported. In difficult tasks, however, face specificity occurs in both single task approaches and task batteries. This suggests different cognitive mechanisms behind face specificity in easy and difficult tasks. In easy tasks, face specificity relies on isolated cognitive sub-processes such as face identity recognition. In difficult tasks, face-specific and task-independent cognitive processes are employed. We propose a descriptive model and argue for FC to be integrated into common taxonomies of intelligence.

Binding Costs in Processing Efficiency as Determinants of Cognitive Ability

Performance in elementary cognitive tasks is moderately correlated with fluid intelligence and working memory capacity. These correlations are higher for more complex tasks, presumably due to increased demands on working memory capacity. In accordance with the binding hypothesis, which states that working memory capacity reflects the limit of a person's ability to establish and maintain temporary bindings (e.g., relations between items or relations between items and their context), we manipulated binding requirements (i.e., 2, 4, and 6 relations) in three choice reaction time paradigms (i.e., two comparison tasks, two change detection tasks, and two substitution tasks) measuring mental speed. Response time distributions of 115 participants were analyzed with the diffusion model. Higher binding requirements resulted in generally reduced efficiency of information processing, as indicated by lower drift rates. Additionally, we fitted bi-factor confirmatory factor analysis to the elementary cognitive tasks to separate basal speed and binding requirements of the employed tasks to quantify their specific contributions to working memory capacity, as measured by Recall-1-Back tasks. A latent factor capturing individual differences in binding was incrementally predictive of working memory capacity, over and above a general factor capturing speed. These results indicate that the relation between reaction time tasks and working memory capacity hinges on the complexity of the reaction time tasks. We conclude that binding requirements and, therefore, demands on working memory capacity offer a satisfactory account of task complexity that accounts for a large portion of individual differences in ability.

Fronto-cerebellar connectivity mediating cognitive processing speed

Processing speed is an important construct in understanding cognition. This study was aimed to control task specificity for understanding the neural mechanisms underlying cognitive processing speed. Forty young adult subjects performed attention tasks of two modalities (auditory and visual) and two levels of task rules (compatible and incompatible). Block-design fMRI captured BOLD signals during the tasks. Thirteen regions of interest were defined with reference to publicly available activation maps for processing speed tasks. Cognitive speed was derived from task reaction times, which yielded six sets of connectivity measures. Mixed-effect LASSO regression revealed six significant paths suggestive of a cerebello-frontal network predicting the cognitive speed. Among them, three are long range (two fronto-cerebellar, one cerebello-frontal), and three are short range (fronto-frontal, cerebello-cerebellar, and cerebello-thalamic). The long-range connections are likely to relate to cognitive control, and the short-range connections relate to rule-based stimulus-response processes. The revealed neural network suggests that automaticity, acting on the task rules and interplaying with effortful top-down attentional control, accounts for cognitive speed.

Mene Mene Tekel Upharsin: Clerical Speed and Elementary Cognitive Speed are Different by Virtue of Test Mode Only

Current taxonomies of intelligence comprise two factors of mental speed, clerical speed (Gs), and elementary cognitive speed (Gt). Both originated from different research traditions and are conceptualized as dissociable constructs in current taxonomies. However, previous research suggests that tasks of one category can be transferred into the other category by simply changing the mode of administration, i.e., in form of a paper-and-pencil test or in from of a computer-based elementary cognitive task. However, cross-mode correlations for specific tasks are usually only moderate. In the present study, mental speed was assessed as a broad construct across different tasks and stimulus materials. This allowed modeling mental speed as a hierarchical construct for paper-and-pencil as well as for computer-based tests. Cross-mode correlations of the respective general factors were moderate (r = 0.64), while the cross-mode correlations of task-specific components depended on task type (r = 0.12 to r = 0.71). Only the g factors of mental speed, but not the task-specific components, were found to be related with working memory capacity as a marker of cognitive ability. The speed general factor modeled across computer-based tests was more highly correlated with working memory capacity (r = 0.66) than the general factor modeled across paper-and-pencil tests (r = 0.46). These findings corroborate a crucial role of the assessment method and imply that validity of speed tests is affected by the choice of the test format.

Mapping Background Variables With Sequential Patterns in Problem-Solving Environments: An Investigation of United States Adults' Employment Status in PIAAC

Adult assessments have evolved to keep pace with the changing nature of adult literacy and learning demands. As the importance of information and communication technologies (ICT) continues to grow, measures of ICT literacy skills, digital reading, and problem-solving in technology-rich environments (PSTRE) are increasingly important topics for exploration through computer-based assessment (CBA). This study used process data collected in log files and survey data from the Programme for the International Assessment of Adult Competencies (PIAAC), with a focus on the United States sample, to (a) identify employment-related background variables that significantly related to PSTRE skills and problem-solving behaviors, and (b) extract robust sequences of actions by subgroups categorized by significant variables. We conducted this study in two phases. First, we used regression analyses to select background variables that significantly predict the general PSTRE, literacy, and numeracy skills, as well as the response time and correctness in the example item. Second, we identified typical action sequences by different subgroups using the chi-square feature selection model to explore these sequences and differentiate the subgroups. Based on the malleable factors associated with problem-solving skills, the goal of this study is to provide information for improving competences in adult education for targeted groups.

Speed Effect Analysis Using the CFA Framework

The paper outlines a method for investigating the speed effect due to a time limit in testing. It is assumed that the time limit enables latent processing speed to influence responses by causing omissions in the case of insufficient speed. Because of processing speed as additional latent source, the customary confirmatory factor model is enlarged by a second latent variable representing latent processing speed. For distinguishing this effect from other method effects, the factor loadings are fixed according to the cumulative normal distribution. With the second latent variable added, confirmatory factor analysis of reasoning data (N=518) including omissions because of a time limit yielded good model fit and discriminated the speed effect from other possible effects due to the item difficulty, the homogeneity of an item subset and the item positions. Because of the crucial role of the cumulative normal distribution for fixing the factor loadings a check of the normality assumption is also reported.

Does the Effect of a Time Limit for Testing Impair Structural Investigations by Means of Confirmatory Factor Models?

The article reports three simulation studies conducted to find out whether the effect of a time limit for testing impairs model fit in investigations of structural validity, whether the representation of the assumed source of the effect prevents impairment of model fit and whether it is possible to identify and discriminate this method effect from another method effect. Omissions due to the time limit for testing were not considered as missing data but as information on the participants' processing speed. In simulated data the presence of a time-limit effect impaired comparative fit index and nonnormed fit index whereas normed chi-square, root mean square error of approximation, and standardized root mean square residual indicated good model fit. The explicit consideration of the effect due to the time limit by an additional component of the model improved model fit. Effect-specific assumptions included in the model of measurement enabled the discrimination of the effect due to the time limit from another possible method effect.

Scoring Alternatives for Mental Speed Tests: Measurement Issues and Validity for Working Memory Capacity and the Attentional Blink Effect

Research suggests that the relation of mental speed with working memory capacity (WMC) depends on complexity and scoring methods of speed tasks and the type of task used to assess capacity limits in working memory. In the present study, we included conventional binding/updating measures of WMC as well as rapid serial visual presentation paradigms. The latter allowed for a computation of the attentional blink (AB) effect that was argued to measure capacity limitations at the encoding stage of working memory. Mental speed was assessed with a set of tasks and scored by diverse methods, including response time (RT) based scores, as well as ex-Gaussian and diffusion model parameterization. Relations of latent factors were investigated using structure equation modeling techniques. RT-based scores of mental speed yielded substantial correlations with WMC but only weak relations with the AB effect, while WMC and the AB magnitude were independent. The strength of the speed-WMC relation was shown to depend on task type. Additionally, the increase in predictive validity across RT quantiles changed across task types, suggesting that the worst performance rule (WPR) depends on task characteristics. In contrast to the latter, relations of speed with the AB effect did not change across RT quantiles. Relations of the model parameters were consistently found for the ex-Gaussian tau parameter and the diffusion model drift rate. However, depending on task type, other parameters showed plausible relations as well. The finding that characteristics of mental speed tasks determined the overall strength of relations with WMC, the occurrence of a WPR effect, and the specific pattern of relations of model parameters, implies that mental speed tasks are not exchangeable measurement tools. In spite of reflecting a general factor of mental speed, different speed tasks possess different requirements, supporting the notion of mental speed as a hierarchical construct.

Hick's law for choice reaction time: A review

In 1952, W. E. Hick published an article in the Quarterly Journal of Experimental Psychology, "On the rate of gain of information." It played a seminal role in the cognitive revolution and established one of the few widely acknowledged laws in psychology, relating choice reaction time to the number of stimulus-response alternatives (or amount of uncertainty) in a task. We review the historical context in which Hick conducted his study and describe his experiments and theoretical analyses. We discuss the article's immediate impact on researchers, as well as challenges to and shortcomings of Hick's law and his analysis, including effects of stimulus-response compatibility, practice, very large set sizes and sequential dependencies. Contemporary modeling developments are also described in detail. Perhaps most impressive about Hick's law is that it continues to spawn research efforts to the present and that it is regarded as a fundamental law of interface design for human-computer interaction using technologies that did not exist at the time of Hick's research.

The Role of Visuospatial Ability in the Raven’s Progressive Matrices

Abstract. Debate surrounding the role of visuospatial ability in performance on the Raven’s Progressive Matrices (RPM) has existed since their conception. This issue has yet to be adequately resolved, and may have implications regarding sex differences in scores. Therefore, this study aimed to examine the relationship between RPM performance, visuospatial ability and fluid ability, and any sex differences in these relationships. Data were obtained from three samples: two University samples completed the Advanced RPM and one population-based sample of men completed the Standard RPM. All samples additionally completed an alternative measure of fluid ability, and one or more measures of visuospatial ability. Structural equation modeling was used to examine the relationships between performance on the visuospatial and fluid ability tests and performance on the RPM. Visuospatial ability was found to significantly contribute to performance on the RPM, over and above fluid ability, supporting the contention that visuospatial ability is involved in RPM performance. No sex differences were found in this relationship, although sex differences in visuospatial ability may explain sex differences in RPM scores.

Compromised Motor Dexterity Confounds Processing Speed Task Outcomes in Stroke Patients

Most conventional measures of information processing speed require motor responses to facilitate performance. However, although not often addressed clinically, motor impairment, whether due to age or acquired brain injury, would be expected to confound the outcome measure of such tasks. The current study recruited 29 patients (20 stroke and 9 transient ischemic attack) with documented reduction in dexterity of the dominant hand, and 29 controls, to investigate the extent to which 3 commonly used processing speed measures with varying motor demands (a Visuo-Motor Reaction Time task, and the Wechsler Adult Intelligence Scale-IV Symbol Search and Coding subtests) may be measuring motor-related speed more so than cognitive speed. Analyses include correlations between indices of cognitive and motor speed obtained from two other tasks (Inspection Time and Pegboard task, respectively) with the three speed measures, followed by hierarchical regressions to determine the relative contribution of cognitive and motor speed indices toward task performance. Results revealed that speed outcomes on tasks with relatively high motor demands, such as Coding, were largely reflecting motor speed in individuals with reduced dominant hand dexterity. Thus, findings indicate the importance of employing measures with minimal motor requirements, especially when the assessment of speed is aimed at understanding cognitive rather than physical function.

Working Memory in Children With Neurocognitive Effects From Sickle Cell Disease: Contributions of the Central Executive and Processing Speed

Children with sickle cell disease (SCD) are at risk for working memory deficits due to multiple disease processes. We assessed working memory abilities and related functions in 32 school-age children with SCD and 85 matched comparison children using Baddeley's working memory model as a framework. Children with SCD performed worse than controls for working memory, central executive function, and processing/rehearsal speed. Central executive function was found to mediate the relationship between SCD status and working memory, but processing speed did not. Cognitive remediation strategies that focus on central executive processes may be important for remediating working memory deficits in SCD.

Joint Modeling of Ability and Differential Speed Using Responses and Response Times

With computerized testing, it is possible to record both the responses of test takers to test questions (i.e., items) and the amount of time spent by a test taker in responding to each question. Various models have been proposed that take into account both test-taker ability and working speed, with the many models assuming a constant working speed throughout the test. The constant working speed assumption may be inappropriate for various reasons. For example, a test taker may need to adjust the pace due to time mismanagement, or a test taker who started out working too fast may reduce the working speed to improve accuracy. A model is proposed here that allows for variable working speed. An illustration of the model using the Amsterdam Chess Test data is provided.

Diversity, dispersion and inconsistency of reaction time measures: effects of age and task complexity

BACKGROUND AND AIMS

Performance variability of reaction time is regarded as an important parameter for cognitive functioning with aging. We investigated three types of variability, diversity (or variability between persons), dispersion (variability across trials within one task) and inconsistency (variability across testing occasions), while distinguishing between decision time and movement time and evaluating performance across comparable complexity levels.

METHODS

A single stratified reaction time test based on tasks with increasing complexity was used to evaluate inter- and intra-performance variability of 27 older (age 75+/-5 years) and 27 younger (age 29+/-7 years) participants, subdividing reaction time into decision and movement components.

RESULTS

There were consistent age and complexity differences for all variability types in our sample. When controlling for processing speed, which was slower in the older group, variability across age groups and task complexity tended to diminish and a more complex picture emerged. The elderly group showed a higher diversity of all reaction time measures, except for movement time, and a higher dispersion of decision time. Task complexity significantly affected the diversity of movement and overall reaction times and the dispersion of all reaction time measures, except for movement time.

CONCLUSIONS

These results highlight the importance of variability in cognitive functioning; it may be an important phenomenon for study and a useful indicator for cognitive deterioration. The reaction time test we propose is easy to use and can be applied in clinical practice.

Perceptual Underconfidence

Experimental interest in human decision making has been fertile in the past two decades. It is generally recognized that answers to questions involving general knowledge tend to produce overconfidence, whereas responses to perceptual tasks often result in underconfidence. While experimental psychologists debated the relative merits of single or dual explanations of these phenomena, differential psychologists suggested that confidence is a trait: Some people have high confidence and others express the opposite, no matter what type of task is undertaken. The current study examined these different perspectives using two complex cognitive and nine perceptual discrimination tasks from different sensory modalities. Findings suggest that underconfidence does not generalize across the perceptual domain, indicating that a more complex account of the miscalibration effect is needed. Such an account should incorporate both task characteristics and individual differences to produce a satisfactory psychological explanation of miscalibration. This point is highlighted by the presence of a strong confidence factor that has loadings from confidence ratings from diverse perceptual and cognitive tasks employed in this study.

Speeded Paper-Pencil Sustained Attention and Mental Speed Tests

Mental speed (MS) and sustained attention (SA) are theoretically distinct constructs. However, tests of MS are very similar to SA tests that use time pressure as an impeding condition. The performance in such tasks largely relies on the participants’ speed of task processing (i.e., how quickly and correctly one can perform the simple cognitive tasks). The present study examined whether SA and MS are empirically the same or different constructs. To this end, 24 paper-pencil and computerized tests were administered to 199 students. SA turned out to be highly related to MS task classes: substitution and perceptual speed. Furthermore, SA showed a very close relationship with the paper-pencil MS factor. The correlation between SA and computerized speed was considerably lower but still high. In a higher-order general speed factor model, SA had the highest loading on the higher-order factor; the higher-order factor explained 88% of SA variance. It is argued that SA (as operationalized with tests using time pressure as an impeding condition) and MS cannot be differentiated, at the level of broad constructs. Implications for neuropsychological assessment and future research are discussed.