Effects of Anthocyanins on Cognition and Vascular Function: A Systematic Review

SCOPE

Good vascular function is crucial for cerebral blood flow and cognitive performance. Diets high in anthocyanins have been shown to improve vascular function and are associated with improvements in cognition. This systematic review investigates randomized controlled trials examining the impact of anthocyanin intake on both cognition and vascular function.

METHODS AND RESULTS

Of the 1486 studies identified through searching Ovid Medline and AMED, PsychInfo, Web of Science, and Scopus, 20 studies are selected which measured cognitive and vascular function. Overall, positive effects on verbal and working memory are observed, which are supported by studies using functional magnetic resonance imaging to demonstrate increased blood flow in brain regions related to these cognitive domains. However, effects of anthocyanins on blood pressure and markers of endothelial function are inconsistent.

CONCLUSION

This systematic review provides evidence for a positive effect of anthocyanins on cognition and insight into the relevance of endothelial function. Anthocyanins are widely available and can be easily consumed in a range of different fruits, vegetables, and other products. Further studies should establish the optimal daily intake of anthocyanins for cardiovascular and cognitive health.

Factorial invariance of the Wechsler Intelligence Scale for Children, Fifth Edition, across the UK, US and Australia & New Zealand

OBJECTIVES

This study examined the factorial invariance of the factor structure of the Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V) across the UK, US and Australia & New Zealand (A&NZ). The factorial equivalence of cognitive assessments should be demonstrated before assuming cross-culture generalizability and interpretations of score comparisons.

METHODS

Data were obtained from the UK, US and A&NZ normative standardizations of the WISC-V. The samples consisted of 415 UK, 2200 US and 528 A&NZ children, aged 6-16. Confirmatory factor analysis was applied separately in each sample to establish the baseline model. Next, tests of factorial invariance were undertaken using the recommended hierarchical approach, firstly across the UK and A&NZ samples and then across the UK and US samples.

RESULTS

The five-factor first-order scoring model was found to be excellent fit across all three samples independently. Strict factorial invariance of the WISC-V was demonstrated firstly across the UK and A&NZ and secondly the UK and US nationally representative standardization samples. Comparison of latent means found small but significant differences in female children across the UK and A&NZ samples.

CONCLUSIONS

Consistent with previous research, these results demonstrate the generality of the WISC-V factor structure across the UK, US and A&NZ. Furthermore, as the WISC-V factor structure aligns with the Cattell-Horn-Carroll (CHC) model of cognitive abilities, the results add further support to the cross-cultural generalizability of the CHC model. Small but significant differences in latent factor scores found across samples support the development and use of local normative data.

What does the Developmental Neuropsychological Assessment-II (NEPSY-II) measure in children ages 7 to 12? A structural and psychometric analysis

The Developmental Neuropsychological Assessment - II (NEPSY-II) is a widely used assessment battery in pediatric settings, but its internal structure has not been adequately examined. This study employed a rational, empirical approach to examine the construct validity of 23 NEPSY-II subtest scores from children ages 7-12 (M = 9.99, SD = 2.76) in the NEPSY-II norming sample (N = 600; 50% girls). Competing higher-order models based on prior research, hypothesized NEPSY-II domains, and conceptual subtest classifications were evaluated via confirmatory factor analysis and a sequential approach to model comparisons. The results supported the multidimensionality of NEPSY-II subtests and the organization of subtests by hypothesized neuropsychological domains. The best fitting model included a general factor and four first-order factors. Factor loadings from the general factor to first-order factors were very strong. However, general factor loadings for most subtests were less than .50 (range = .21-.69, M = .44), and domain-specific effects for all subtests, independent of the general factor, were even lower (range = .00-.45, M = .44). Interestingly, all subtests demonstrated strong subtest-specific effects, but it is not clear what construct(s) the subtest-specific effects represent. Findings support NEPSY-II authors' emphasis on subtest-level interpretations rather than composite-level interpretations and highlight that NEPSY-II subtest scores should be interpreted carefully and with caution.

Combining neuropsychological assessment and structural neuroimaging to identify early Alzheimer's disease in a memory clinic cohort

INTRODUCTION

The current study examined the contributions of comprehensive neuropsychological assessment and volumetric assessment of selected mesial temporal subregions on structural magnetic resonance imaging (MRI) to identify patients with amnestic mild cognitive impairment (aMCI) and mild probable Alzheimer's disease (AD) dementia in a memory clinic cohort.

METHODS

Comprehensive neuropsychological assessment and automated entorhinal, transentorhinal, and hippocampal volume measurements were conducted in 40 healthy controls, 38 patients with subjective memory symptoms, 16 patients with aMCI, 16 patients with mild probable AD dementia. Multinomial logistic regression was used to compare the neuropsychological and MRI measures.

RESULTS

Combining the neuropsychological and MRI measures improved group membership prediction over the MRI measures alone but did not improve group membership prediction over the neuropsychological measures alone.

CONCLUSION

Comprehensive neuropsychological assessment was an important tool to evaluate cognitive impairment. The mesial temporal volumetric MRI measures contributed no diagnostic value over and above the determinations made through neuropsychological assessment.

Investigating the Latent Structure of Executive Function in the Delis-Kaplan Executive Function System Using Cattell-Horn-Carroll Theory

OBJECTIVE

To replicate a seven-factor model previously reported for the Delis-Kaplan Executive Function System (D-KEFS).

METHOD

This study used the D-KEFS standardization sample including 1,750 non-clinical participants. Several seven-factor models previously reported for the D-KEFS were re-evaluated using confirmatory factor analysis (CFA). Previously published bi-factor models were also tested. These models were compared with a three-factor a priori model based on Cattell-Horn-Carroll (CHC) theory. Measurement invariance was examined across three age cohorts.

RESULTS

All previously reported models failed to converge when tested with CFA. None of the bi-factor models converged after large numbers of iterations, suggesting that bi-factor models are ill-suited to represent the D-KEFS scores as reported in the test manual. Although poor fit was initially observed for the three-factor CHC model, inspection of modification indices showed potential for improvement by including method effects via correlated residuals for scores derived from similar tests. The final CHC model showed good to excellent fit and strong metric measurement invariance across the three age cohorts with minor exceptions for a subset of Fluency parameters.

CONCLUSIONS

CHC theory extends to the D-KEFS, supporting findings from previous studies that executive functions can be integrated into CHC theory.

A review of the effects of mushrooms on mood and neurocognitive health across the lifespan

Mushrooms contain bioactive compounds with documented antioxidant and anti-inflammatory actions. Here, we present a systematic evaluation of epidemiological and clinical studies that investigate the role of mushrooms, either as a separate or integral dietary component, on neurocognition and mood. Following a search of four databases, a total of 34 human studies examining the effect of different mushrooms across varying age cohorts and health statuses were selected for inclusion. Epidemiological studies included in this review (n = 24) revealed a significant benefit of dietary patterns that included mushrooms of any species on cognition and mood in both healthy and compromised populations. However, the results obtained from intervention studies (n = 10) were mixed. Studies mainly investigated Lion's Mane (Hericium erinaceus), showing some enhancement of mood and cognitive function in middle-aged and older adults. Further acute and chronic human intervention studies are needed, using adequate sample sizes, employing appropriately sensitive neurocognitive tests, and investigating a range of dietary mushrooms, to confirm the effects of mushroom supplementation on neurocognition and mood in humans.

Validation of the Cognitive Reserve Index Questionnaire (CRIq) in Arabic

Cognitive reserve is the adaptability of cognitive processes in the face of brain aging and pathology. This study aimed to validate the Arabic version of the Cognitive Reserve Index Questionnaire (CRIq) in a healthy Lebanese sample. CRIq assesses cognitive reserve through three domains: education, working activity, and leisure time. Statistical measures, including descriptive and regression analysis along with structural equation modeling, were utilized to investigate the convergent and discriminant validity of the CRIq, incorporating fluid intelligence (Gf) and measures of cognitive function, long-term memory encoding and retrieval (Glr), and processing speed (Gs). Results from 174 participants revealed that the activities assessed by the CRIq-Arabic were comparable to the original CRIq study, with slight cultural differences. The internal consistency of the CRIq-Arabic was good (Cronbach's α = 0.88), indicating reliability. Convergent validity was confirmed, with moderate to high loadings on the cognitive reserve latent construct. Discriminant validity was supported as correlations between cognitive reserve variables and non-target constructs (Gf, Glr, and Gs) were less than 1. The findings provide an initial psychometric validation of the CRIq-Arabic. Further research of clinical samples is needed to enhance its utility in neuropsychological practice.

Cross-National Generalizability of WISC-V and CHC Broad Ability Constructs across France, Spain, and the US

The Cattell-Horn-Carroll (CHC) model is based on psychometric cognitive ability research and is the most empirically supported model of cognitive ability constructs. This study is one in a series of cross-national comparisons investigating the equivalence and generalizability of psychological constructs which align with the CHC model. Previous research exploring the cross-cultural generalizability of cognitive ability measures concluded that the factor analytic models of cognitive abilities generalize across cultures and are compatible with well-established CHC constructs. The equivalence of the psychological constructs, as measured by the Wechsler Intelligence Scale for Children-Fifth Edition (WISC-V), has been established across English-speaking samples. However, few studies have explored the equivalence of psychological constructs across non-English speaking, nationally representative samples. This study explored the equivalence of the WISC-V five-factor model across standardization samples from France, Spain, and the US. The five-factor scoring model demonstrated excellent fit across the three samples independently. Factorial invariance was investigated and the results demonstrated strict factorial invariance across France, Spain, and the US. The results provide further support for the generalizability of CHC constructs across Western cultural populations that speak different languages and support the continued use and development of the CHC model as a common nomenclature and blueprint for cognitive ability researchers and test developers. Suggestions for future research on the CHC model of intelligence are discussed.

Exposure to greenspace and bluespace and cognitive functioning in children - A systematic review

BACKGROUND

The field of greenspace and bluespace research in relation to cognitive outcomes is rapidly growing. Several systematic reviews have already been published on this topic but none of them are specific to cognitive outcomes in the entire age range of children. Moreover, only a few of them have examined the effects of bluespace in addition to greenspace. Also, theses reviews are focused either only on observational studies or experimental studies. Our systematic review focuses on cognitive outcomes in relation to greenspace and bluespace in children and adolescents aged 0-18; it captures both observational and experimental studies. Cognitive outcomes are presented according to an evidence-based taxonomy of human cognitive abilities: the Cattell-Horn-Carroll (CHC) theory.

METHODS

We conducted searches in the PubMed and PsychInfo databases, from their inception dates to 17 December 2021. We used three-text terms related to outcome, exposure, and population as well as MeSH terms for outcome and population. Further, the reference lists and existing reviews were searched ("snowball" search) until 21 April 2022 to detect additional studies. For the results reporting, we followed the updated guidelines of the Preferred Reporting Items for Systematic reviews and Meta Analyses (PRISMA). We included observational and experimental studies on greenspace or bluespace exposure in relation to cognitive functioning, published in English, German, or Polish. Two reviewers independently checked study eligibility and extracted data. Two reviewers evaluated the risk of bias according to the Office of Health Assessment and Translation (OHAT) tool. At all stages, discrepancies between the two reviewers were solved via discussion with a third reviewer.

RESULTS

Records identified from PubMed (n = 2030) and PsycINFO (n = 1168) were deduplicated and screened. Twenty one reports were first selected. The "snowball" search revealed 16 additional reports. Altogether, 39 studies (17 experimental and 22 observational) published in 37 reports were qualified. The data extraction showed that the methodology used in the studies was heterogenous and the findings were inconsistent. The majority of the studies investigated attentional functioning, which we subdivided into two categories according to the CHC theory: attentional control and reaction and decision speed (12 studies) and attentional control and processing speed (10 studies). Eleven studies investigated working memory and/or short-term memory that we categorized as CHC working memory capacity. Nine studies investigated intellectual functioning, which we categorized as CHC general ability, fluid reasoning, and comprehension-knowledge. Two studies investigated visual-spatial skills, which we categorized as CHC visual processing and psychomotor speed. One study measured parent-reported attention; two studies examined early childhood/cognitive development; three studies examined decision-making and self-regulation, which can be categorized as several CHC theory abilities.

DISCUSSION

The heterogeneity of the included studies does not permit clear conclusions for our review. In accordance with previous systematic reviews, greenspace and bluespace were not more strongly related to a particular domain of cognitive functioning than other cognitive domains, and no effects of age or type of exposure assessment on the association between nature and cognition were detected. Further research is needed, including state-of-the-art of assessment of cognitive outcomes and diverse exposure assessment methods within both observational and experimental approaches. Expertise will be required in several domains, such as environmental epidemiology, cognitive psychology, and neuropsychology. Systematic review registration number (INPLASY): 202220018.

Carroll's Three-Stratum (3S) Cognitive Ability Theory at 30 Years: Impact, 3S-CHC Theory Clarification, Structural Replication, and Cognitive-Achievement Psychometric Network Analysis Extension

Carroll's treatise on the structure of human cognitive abilities is a milestone in psychometric intelligence research. Thirty years later, Carroll's work continues to influence research on intelligence theories and the development and interpretation of intelligence tests. A historical review of the relations between the 3S and CHC theories necessitates the recommendation that the theories of Cattell, Horn, and Carroll be reframed as a family of obliquely correlated CHC theories-not a single CHC theory. Next, a previously unpublished Carroll exploratory factor analysis of 46 cognitive and achievement tests is presented. A complimentary bifactor analysis is presented that reinforces Carroll's conclusion that his 3S model more accurately represents the structure of human intelligence than two prominent alternative models. Finally, a Carroll-recommended higher-stratum psychometric network analysis (PNA) of CHC cognitive, reading, and math variables is presented. The PNA results demonstrate how PNA can complement factor analysis and serve as a framework for identifying and empirically evaluating cognitive-achievement causal relations and mechanisms (e.g., developmental cascade and investment theories), with an eye toward improved cognitive-achievement intervention research. It is believed that Carroll, given his long-standing interest in school learning, would welcome the integration of theory-driven factor and PNA research.

Dietary Flavonoids and Human Cognition: A Meta-Analysis

Improving cognition is important in all age groups, from performance in school examinations to prevention of cognitive decline in later life. Dietary polyphenols, in particular flavonoids, have been examined for their benefits to cognitive outcomes. This meta-analysis evaluates the effects of dietary flavonoids on cognition across the lifespan. In January 2020 databases were searched for randomized controlled trials investigating flavonoid effects on human cognition. Eighty studies, comprising 5519 participants, were included in the final meta-analysis. The global analysis indicates dietary flavonoids induced significant benefit to cognitive performance (g = 0.148, p < 0.001), with subgroup analyses revealing that cocoa (g = 0.224, p = 0.036), ginkgo (g = 0.187, p ≤ 0.001), and berries (g = 0.149, p = 0.009) yielded the most notable improvements. Significant benefits were observed from chronic studies, in middle-aged and older adults, and with low and medium doses. The domains of long-term memory, processing speed, and mood showed sensitivity to flavonoid intervention. This meta-analysis provides evidence for the positive effects of flavonoids on cognition and highlights several moderating factors. Flavonoid-based dietary interventions therefore potentially offer a highly accessible, safe, and cost-effective treatment to help tackle the burden of cognitive decline.

Treatments for objective and subjective cognitive functioning in young people with depression: Systematic review of current evidence

AIM

Cognitive deficits are recognized features of depressive disorders in youth aged 12-25. These deficits are distressing, predict functional impairment and limit the effectiveness of psychological therapies. Cognitive enhancement using behavioural, biochemical or physical treatments may be useful in young people with depression, but studies have not been synthesized. The aim was to systematically review the evidence for treatments for objective and subjective cognitive functioning, and their acceptability and functional outcomes in people aged 12-25 with depression.

METHOD

Three electronic databases were searched for articles using pre-specified criteria. Pharmacological treatments were not eligible. Risk of bias was rated using the Cochrane Collaboration's revised risk-of-bias tool. Dual full-text article screening, data extraction and quality ratings were completed.

RESULTS

Twelve studies were included for review (median participant age: 20.39 years), five of which were randomized-controlled trials (RCTs). Sample sizes were generally small (median = 23; range: 9-46). Eight studies investigated behavioural treatments including aerobic exercise, cognitive training and education or strategy-based methods. Four studies examined repetitive transcranial magnetic brain stimulation (rTMS). Most behavioural treatments revealed preliminary evidence of improved cognitive function in youth depression. Consent rates were greatest for exercise- and education-based approaches, which may indicate higher acceptability levels. Findings from rTMS trials were mixed, with only half showing cognitive improvement. Functional outcomes were reported by three behavioural treatment trials and one rTMS trial, with functional improvement reported only in the former. Some concern of risk of bias was found in each RCT.

CONCLUSION

Behavioural treatments, such as exercise, cognitive training and education/strategy-focused techniques, show encouraging results and appear to be acceptable methods of addressing cognitive deficits in youth depression based on participation rates. Brain stimulation and biochemical treatments (e.g., nutrient-based treatment) require further investigation.

Structural Equation Modeling of Common Cognitive Abilities in Preschool-Aged Children Using WPPSI-IV and BRIEF-P

Various studies have addressed the relationship between intelligence and executive functions (EF). There is widespread agreement that EF in preschool children is a unitary construct in which the subordinate factors of Updating, Inhibition, and Shifting are still undifferentiated and correlate moderately with a general factor of intelligence (g). The aim of this study is to investigate the common structural relationship between these two constructs using confirmatory factor analysis. Furthermore, we intend to close the gap of more daily life-associated executive functions and replicate findings in preschool-aged children. Data from a sample of N = 124 average developed children without severe impairments (aged 4 years 0 months–6 years 11 months) were analyzed using the data pool of the standardization and validation studies on the German Wechsler Preschool and Primary Scale of Intelligence—Fourth Edition. Additionally, Executive functions were assessed using a standardized parent-completed questionnaire (BRIEF-P) on their children’s everyday behavior. A second-order factor solution revealed that a model with a loading of the common factor of general intelligence (g-factor) onto the EF factor fits the data best. To specify possible method effects due to different sources of measurements, a latent method factor was generated. The results indicate a heterogeneous method effect and a decreasing factor loading from g on to EF while controlling for the method factor.

Exploring the Semantic Structure of WMS-IV Verbal Paired Associates using the Hub-and-Spoke Model

OBJECTIVES

This study aimed to identify a well-fitting and theoretically justified item-level latent factor structure for the Wechsler Memory Scales (WMS)-IV verbal paired associates (VerbalPA) subtest to facilitate the ease and accuracy of score interpretations for patients with lateralized temporal lobe epilepsy (TLE).

METHODS

Archival data were used from 250 heterogeneous neurosciences patients who were administered the WMS-IV as part of a standard neuropsychological assessment. Three theoretically motivated models for the latent structure of VerbalPA were tested using confirmatory factor analysis. The first model, based on cognitive principles of semantic processing from hub-and-spoke theory, tested whether performance is related to specific semantic features of target words. The second, motivated by the Cattell-Horn-Carroll (CHC) model of cognitive abilities, investigated whether the associative properties of items influence performance. A third, Hybrid model tested whether performance is related to both semantic and associative properties of items. The best-fitting model was tested for diagnostic group effects contrasting the heterogeneous neuroscience patients with subsets of left and right TLE (n = 51, n = 26, respectively) patients.

RESULTS

The Hybrid model was found to have the best fit. Patients with left TLE scored significantly less well than the heterogeneous neurosciences sample on selected semantic factor scores, although the effect size was small.

CONCLUSIONS

Future editions of the WMS may consider implementing a semantic scoring structure for the VerbalPA to facilitate test score interpretation. Additionally, these results suggest that principles of hub-and-spoke theory may be integrated into CHC cognitive ability taxonomy.

Network neuropsychology: The map and the territory

In "network neuropsychology", network modelling and graph theory is applied to the neuropsychological test scores of patients with neurological disorders to investigate cognitive functioning. This review identifies the emerging literature on several disorders before focusing on the assumptions about cognition underlying the studies; specifically, that cognition can be thought of as a network of interrelated variables and that changes in these interrelationships, or cognitive rearrangement, can occur in neurological disorders. Next the review appraises how well network models can provide a "map" of this cognitive "territory". In particular, the review considers the lack of correspondence between the variables and properties of network models and cognitive functioning. The challenges of explicitly accounting for latent cognitive constructs and making inferences about cognition based on associative, as opposed to dissociative, methods are also discussed. It is concluded that the validity of network neuropsychological models is yet to be established and that cognitive theory and experiments, as well as network models, are needed to develop and interpret better maps.

The Relationship Between Cognitive Functioning and Symptoms of Depression, Anxiety, and Post-Traumatic Stress Disorder in Adults with a Traumatic Brain Injury: a Meta-Analysis

A thorough understanding of the relationship between cognitive test performance and symptoms of depression, anxiety, or post-traumatic stress disorder (PTSD) in people with traumatic brain injury (TBI) is important given the high prevalence of these emotional symptoms following injury. It is also important to understand whether these relationships are affected by TBI severity, and the validity of test performance and symptom report. This meta-analysis was conducted to investigate whether these symptoms are associated with cognitive test performance alterations in adults with a TBI. This meta-analysis was prospectively registered on the PROSPERO International Prospective Register of Systematic Reviews website (registration number: CRD42018089194). The electronic databases Medline, PsycINFO, and CINAHL were searched for journal articles published up until May 2020. In total, 61 studies were included, which enabled calculation of pooled effect sizes for the cognitive domains of immediate memory (verbal and visual), recent memory (verbal and visual), attention, executive function, processing speed, and language. Depression had a small, negative relationship with most cognitive domains. These relationships remained, for the most part, when samples with mild TBI (mTBI)-only were analysed separately, but not for samples with more severe TBI (sTBI)-only. A similar pattern of results was found in the anxiety analysis. PTSD had a small, negative relationship with verbal memory, in samples with mTBI-only. No data were available for the PTSD analysis with sTBI samples. Moderator analyses indicated that the relationships between emotional symptoms and cognitive test performance may be impacted to some degree by exclusion of participants with atypical performance on performance validity tests (PVTs) or symptom validity tests (SVTs), however there were small study numbers and changes in effect size were not statistically significant. These findings are useful in synthesising what is currently known about the relationship between cognitive test performance and emotional symptoms in adults with TBI, demonstrating significant, albeit small, relationships between emotional symptoms and cognitive test performance in multiple domains, in non-military samples. Some of these relationships appeared to be mildly impacted by controlling for performance validity or symptom validity, however this was based on the relatively few studies using validity tests. More research including PVTs and SVTs whilst examining the relationship between emotional symptoms and cognitive outcomes is needed.

The Brain Metabolic Signature in Superagers Using In Vivo 1H-MRS: A Pilot Study

BACKGROUND AND PURPOSE

Youthful memory performance in older adults may reflect an underlying resilience to the conventional pathways of aging. Subjects having this unusual characteristic have been recently termed "superagers." This study aimed to explore the significance of imaging biomarkers acquired by ¹H-MRS to characterize superagers and to differentiate them from their normal-aging peers.

MATERIALS AND METHODS

Fifty-five patients older than 80 years of age were screened using a detailed neuropsychological protocol, and 25 participants, comprising 12 superagers and 13 age-matched controls, were statistically analyzed. We used state-of-the-art 3T ¹H-MR spectroscopy to quantify 18 neurochemicals in the posterior cingulate cortex of our subjects. All ¹H-MR spectroscopy data were analyzed using LCModel. Results were further processed using 2 approaches to investigate the technique accuracy: 1) comparison of the average concentration of metabolites estimated with Cramer-Rao lower bounds <20%; and 2) calculation and comparison of the weighted means of metabolites' concentrations.

RESULTS

The main finding observed was a higher total N-acetyl aspartate concentration in superagers than in age-matched controls using both approaches (P = .02 and P = .03 for the weighted means), reflecting a positive association of total N-acetyl aspartate with higher cognitive performance.

CONCLUSIONS

¹H-MR spectroscopy emerges as a promising technique to unravel neurochemical mechanisms related to cognitive aging in vivo and providing a brain metabolic signature in superagers. This may contribute to monitoring future interventional therapies to avoid or postpone the pathologic processes of aging.

Brief, Performance-Based Cognitive Screening in Youth Aged 12-25: A Systematic Review

OBJECTIVE

Cognitive screening is an efficient method of detecting cognitive impairment in adults and may signal need for comprehensive assessment. Cognitive screening is not, however, routinely used in youth aged 12-25, limiting clinical recommendations. The aims of this review were to describe performance-based cognitive screening tools used in people aged 12-25 and the contexts of use, review screening accuracy in detecting cognitive impairment relative to an objective reference standard, and evaluate the risk of bias of included studies.

METHOD

Electronic databases (Scopus, Medline, PsychINFO, and ERIC) were searched for relevant studies according to pre-determined criteria. Risk of bias was rated using the Quality Assessment of Diagnostic Accuracy Studies-2. Dual screening, extraction, and quality ratings occurred at each review phase.

RESULTS

Twenty studies met the review inclusion criteria. A diverse range of screening tools (length, format) were used in youth aged 12-25 with or without health conditions. Six studies investigating cognitive screening were conducted as primary accuracy studies and reported some relevant psychometric parameters (e.g., sensitivity and specificity). Fourteen studies presented correlational data to investigate the cognitive measure utility. Studies generally presented limited data on classification accuracy, which impacted full screening tool appraisal. Risk of bias was high (or unclear) in most studies with poor adherence to the Standards for Reporting Diagnostic Accuracy Studies (STARD) criteria.

CONCLUSIONS

Few, high quality studies have investigated the utility of cognitive screening in youth aged 12-25, with no screening measure emerging as superior at detecting cognitive impairment in this age group.

Interictal Cognitive Deficits in Migraine Sufferers: A Meta-Analysis

While a significant proportion of the population suffer from migraine, the existing research literature does not provide a clear indication as to whether migraineurs experience objective cognitive deficits outside of acute migraine attacks. This meta-analysis was conducted to investigate which cognitive domains if any were affected by migraine, by synthesising the existing research quantitatively. The meta-analysis was prospectively registered with the PROSPERO International prospective register of systematic reviews (registration no.: CRD42019134138). A search of the electronic databases PubMed, Ovid MEDLINE, and PsycINFO was conducted for journal articles published between January 1980 and January 2020. Seventeen studies met the inclusion criteria, allowing for the calculation of pooled effect sizes between migraineurs (with and without aura) and healthy controls in the several cognitive domains. During the interictal period, migraineurs demonstrated a moderate, negative effect on complex attention immediate and delayed memory, spatial cognition, and executive functioning. This effect was not attributable to migraine history, attack frequency, or participant age. However, the lack of performance validity testing, and limited data on mood symptomatology and migraine medication use in the included studies may be confounds potentially overestimating the magnitude of effect. Comparison with a clinical control group, which may have accounted for some these extraneous variables, was unable to be conducted. Recommendations for comprehensive future neuropsychological research are provided.

How do we measure attention? Using factor analysis to establish construct validity of neuropsychological tests

We investigated whether standardized neuropsychological tests and experimental cognitive paradigms measure the same cognitive faculties. Specifically, do neuropsychological tests commonly used to assess attention measure the same construct as attention paradigms used in cognitive psychology and neuroscience? We built on the “general attention factor”, comprising several widely used experimental paradigms (Huang et al., 2012). Participants (n = 636) completed an on-line battery (TestMyBrain.org) of six experimental tests [Multiple Object Tracking, Flanker Interference, Visual Working Memory, Approximate Number Sense, Spatial Configuration Visual Search, and Gradual Onset Continuous Performance Task (Grad CPT)] and eight neuropsychological tests [Trail Making Test versions A & B (TMT-A, TMT-B), Digit Symbol Coding, Forward and Backward Digit Span, Letter Cancellation, Spatial Span, and Arithmetic]. Exploratory factor analysis in a subset of 357 participants identified a five-factor structure: (1) attentional capacity (Multiple Object Tracking, Visual Working Memory, Digit Symbol Coding, Spatial Span), (2) search (Visual Search, TMT-A, TMT-B, Letter Cancellation); (3) Digit Span; (4) Arithmetic; and (5) Sustained Attention (GradCPT). Confirmatory analysis in 279 held-out participants showed that this model fit better than competing models. A hierarchical model where a general cognitive factor was imposed above the five specific factors fit as well as the model without the general factor. We conclude that Digit Span and Arithmetic tests should not be classified as attention tests. Digit Symbol Coding and Spatial Span tap attentional capacity, while TMT-A, TMT-B, and Letter Cancellation tap search (or attention-shifting) ability. These five tests can be classified as attention tests.

Ideational Fluency in Patients with Rheumatoid Arthritis

BACKGROUND

Neuropsychiatric symptoms have been well documented in several systemic inflammatory conditions, for example, systemic lupus erythematosus (SLE). Increased prevalence of cognitive decline and psychiatric issues has been reported in patients with rheumatoid arthritis (RA). However, there is limited evidence of which exact cognitive domains are affected and to what degree.

AIM

To test the performance of cognition in the domain of ideational fluency (Thing Categories Test in particular) in patients with RA and compare the results with the general population and to the results with cognitive and depression screening scores in both groups.

METHODS

Patient Health Questionnaire 9 (PHQ-9), Generalized Anxiety Disorder 7 (GAD-7) assessment, Montreal Cognitive Assessment (MoCA), and Thing Categories Test (TCT) were used to evaluate patients with RA, as well as the control group.

RESULTS

Twenty patients with RA and 20 controls were tested, with 7 and 4 men, and 13 and 16 women in the study and control group, respectively. Average scores in TCT at three minutes were 7.50 (IQR6.0-10.0) and 6.0 (IQR3.0-8.0) for category "blue"; 17.50 (IQR15.0-19.0) and 16.0 (10.0-18.0) for category "round" in the control and study group, respectively. A statistically significant difference was established between the study and the control group in TCT for the category "blue" (p<0.025). The average score for GAD7 was 2.0 (IQR 0.0-5.75) and 3.0 (IQR0.50-6.00) in the control and study group, respectively. The average score for PHQ-9 was 2.0 (IQR0.25-4.75) and 4.0 (IQR2.00-5.50) in the control and study group, respectively. Finally, the average score for the MoCA scale was 27.0 (IQR25.25-28.00) and 26.0 (IQR23.50-28.00) in the control and study group, respectively.

CONCLUSION

Preliminary evidence suggests that RA at least partially affects the cognitive domain of ideational fluency. However, further research with larger experimental groups is needed to provide more conclusive evidence.

Associations Between Subjective Tinnitus and Cognitive Performance: Systematic Review and Meta-Analyses

Tinnitus is the perception of sound in the absence of a corresponding external sound source, and bothersome tinnitus has been linked to poorer cognitive performance. This review comprehensively quantifies the association between tinnitus and different domains of cognitive performance. The review protocol was preregistered and published in a peer-reviewed journal. The review and analyses were reported according to Preferred Reporting Items for Systematic Review and Meta-analysis guidelines. Peer-reviewed literature was searched using electronic databases to find studies featuring participants with tinnitus who had undertaken measures of cognitive performance. Studies were assessed for quality and categorized according to an established cognitive framework. Random-effects meta-analyses were performed on various cognitive domains with potential moderator variables assessed where possible. Thirty-eight records were included in the analysis from a total of 1,863 participants. Analyses showed that tinnitus is associated with poorer executive function, processing speed, general short-term memory, and general learning and retrieval. Narrow cognitive domains of Inhibition and Shifting (within executive function) and learning and retrieval (within general learning and retrieval) were also associated with tinnitus.

The Latent-Variable Structure of the Addenbrooke's Cognitive Examination-Revised

OBJECTIVES

To establish a theoretically justified factor structure for the Addenbrooke's Cognitive Examination-Revised (ACE-R).

METHODS

Our sample comprised 288 patients with Parkinson's disease (179 men and 109 women). The mean age of participants was 66.66 (SD = 8.93). Confirmatory factor analysis (CFA) was used to evaluate the test developers' five-factor model of the ACE-R, and alternative models as guided by the Cattell-Horn-Carroll (CHC) theory. Exploratory structural equation modeling (ESEM) was also employed to examine alternative factor structures to ensure that a good candidate model was not overlooked.

RESULTS

A three-factor CHC-guided CFA and a similar three-factor ESEM model both showed acceptable overall fit, and interpretable factor structures. The three-factor CFA model showed two factors of pure CHC constructs: acquired knowledge (Gc), and visuospatial ability (Gv), and one combined factor, namely, long-term memory retrieval, fluency, and working memory (Glr-Gsm). The three-factor ESEM model showed three factors essentially in line with the CFA results.

CONCLUSION

The three-factor CHC-guided CFA model was selected as the best model to guide clinical interpretation of cognitive variables underlying ACE-R scores.

Evidence of Validity for a Newly Developed Digital Cognitive Test Battery

Clinical practice still relies heavily on traditional paper-and-pencil testing to assess a patient’s cognitive functions. Digital technology has the potential to be an efficient and powerful alternative, but for many of the existing digital tests and test batteries the psychometric properties have not been properly established. We validated a newly developed digital test battery consisting of digitized versions of conventional neuropsychological tests. Two confirmatory factor analysis models were specified: a model based on traditional neuropsychological theory and expert consensus and one based on the Cattell-Horn-Carroll (CHC) taxonomy. For both models, the outcome measures of the digital tests loaded on the cognitive domains in the same way as established in the neuropsychological literature. Interestingly, no clear distinction could be made between the CHC model and traditional neuropsychological model in terms of model fit. Taken together, these findings provide preliminary evidence for the structural validity of the digital cognitive test battery.

The Factor Structure of Cognitive Functioning in Cognitively Healthy Participants: a Meta-Analysis and Meta-Analysis of Individual Participant Data

Many neuropsychologists are of the opinion that the multitude of cognitive tests may be grouped into a much smaller number of cognitive domains. However, there is little consensus on how many domains exist, what these domains are, nor on which cognitive tests belong to which domain. This incertitude can be solved by factor analysis, provided that the analysis includes a broad range of cognitive tests that have been administered to a very large number of people. In this article, two such factor analyses were performed, each combining multiple studies. However, because it was not possible to obtain complete multivariate data on more than the most common test variables in the field, not all possible domains were examined here. The first analysis was a factor meta-analysis of correlation matrices combining data of 60,398 healthy participants from 52 studies. Several models from the literature were fitted, of which a version based on the Cattell-Horn-Carroll (CHC) model was found to describe the correlations better than the others. The second analysis was a factor analysis of the Advanced Neuropsychological Diagnostics Infrastructure (ANDI) database, combining scores of 11,881 participants from 54 Dutch and Belgian studies not included in the first meta-analysis. Again, the model fit was better for the CHC model than for other models. Therefore, we conclude that the CHC model best characterizes both cognitive domains and which test belongs to each domain. Therefore, although originally developed in the intelligence literature, the CHC model deserves more attention in neuropsychology.

Executive functions and intelligence from the CHC theory perspective: Investigating the correspondence between the WAIS-IV and the NAB Executive Functions Module

Substantial overlap between executive functions (EFs) and intelligence has been reported. Yet further research is required with respect to how the specific components of the two constructs are interrelated. The present study was aimed at exploring the relationship between EFs and intelligence by examining the latent structure of the Wechsler Adult Intelligence Scale (WAIS-IV) and the Executive Functions Module from the Neuropsychological Assessment Battery (NAB). The aim was also to test the correspondence of the two measures to the Cattell-Horn-Carroll (CHC) theory. 205 healthy participants, aged 18-89 years, were administered the NAB and WAIS-IV. Confirmatory factor analysis (CFA) was employed to explore the latent constructs underlying the two test batteries. Models based on the current WAIS-IV index structure showed worse model fit than models based on the CHC theory. In particular, factors representing broad CHC abilities comprehension knowledge (Gc), fluid reasoning (Gf), visual processing (Gv), processing speed (Gs), and working memory capacity (Gwm) proved model fit improvement. The best model fit, however, provided a five-factor model combining the Gf and Gwm abilities into one factor and additionally including a retrieval fluency (Gr) factor. The results demonstrate strong relationships between the WAIS-IV and the NAB Executive Functions Module and suggest substantial overlap between EFs and intelligence within the CHC framework. Nevertheless, according to the recent update of the CHC theory, the NAB fluency tasks may represent a distinct EF factor comprising Gr abilities independent from the WAIS-IV.

A Meta-Analysis of Relationships between Measures of Wisconsin Card Sorting and Intelligence

The Wisconsin Card Sorting Test (WCST) represents a widely utilized neuropsychological assessment technique for executive function. This meta-analysis examined the discriminant validity of the WCST for the assessment of mental shifting, considered as an essential subcomponent of executive functioning, against traditional psychometric intelligence tests. A systematic search was conducted, resulting in 72 neuropsychological samples for the meta-analysis of relationships between WCST scores and a variety of intelligence quotient (IQ) domains. The study revealed low to medium-sized correlations with IQ domains across all WCST scores that could be investigated. Verbal/crystallized IQ and performance/fluid IQ were indistinguishably associated with WCST scores. To conclude, the WCST assesses cognitive functions that might be partially separable from common conceptualizations of intelligence. More vigorous initiatives to validate putative indicators of executive function against intelligence are required.

On differentiating auditory processing disorder (APD) from attention deficit disorder (ADD): an illustrative example using the Cattell-Horn-Carroll (CHC) model of cognitive abilities

Objective: To clarify the distinction between Auditory Processing Disorder (APD) and Attention Deficit Disorder (ADD) using the CHC Model.Design: A cross-sectional study compared responses of caregivers about their children's behaviour to identify characteristics of APD (CHC Model) and ADD (DSM-5).Study Sample: Caregivers, mostly mothers (92%), of 149 children (M 61%; F 39%) aged from 6 to 16 years, referred for "Auditory Processing Assessment" of their child, were shown an A4 card displaying the characteristics of AP from the CHC Model on one side, and of ADD from DSM-5 on the other. Both sides were untitled. For each side, caregivers were asked if the characteristics were true of their child using a Conners-type four-point scale.Results: The majority of children were rated by caregivers as displaying characteristics of ADD, rather than an APD problem. Comparing problems with AP vs. problems with ADD gave: Wilcoxon T = 9.71; z = 4.86, p < 0.001.Conclusion: The finding that most children referred for an AP Assessment showed characteristics of ADD was surprising. Given the continuing audiological controversies about the nature of AP and about differentiating AP disorders from ADD, the CHC Model offers a different and informative perspective.

A Systematic Review of Neurocognitive Functioning in Behçet's Disease

Behçet's disease (BD) is a vascular, inflammatory multisystem disorder with neuro-Behçet's (NBD) diagnosed in a subset of patients with neurological manifestations. The objective of this review was to determine whether neurocognitive dysfunction is observed in BD, in which neurocognitive domains, and whether there are differences in rates of dysfunction observed between BD and NBD groups. Studies of any methodology were included that reported results from standardized neurocognitive assessment measures in participants with BD or NBD. Twelve group comparison studies met the criteria for inclusion in the review (totalling 284 BD and 157 NBD participants), as well as 17 case study/series papers (11 BD, 35 NBD). Issues with blinding, incomplete data reporting and selective reporting bias were found across the group and case study/series papers, as well as inadequate statistical adjustment for multiple comparisons in the group studies, and the lack of the use of appropriate norms or adjustment for premorbid ability in the case series/studies papers. These quality issues impacted on the conclusions that could be drawn from the current literature. Neurocognitive dysfunction was found in NBD compared to health controls (HC) in a higher proportion of results across studies, than in comparisons between BD and HC groups. The domains in which neurocognitive attenuation was most often reported were visual spatial ability, working memory and acquired knowledge, with more than 25% of these results showing significantly lower functioning in both the BD and NBD groups compared to HC. More than 25% of the processing speed and long-term memory encoding and retrieval results were also lower for the NBD group, compared to HC. Group comparisons between NBD and multiple sclerosis participants indicated few significant differences in neurocognitive test results. The majority of case study/series participants were found to have some degree of attenuated neurocognitive functioning, as defined by case study/series authors.

Commenting on the "Great Debate": General Abilities, Specific Abilities, and the Tools of the Trade

We review papers in the special issue regarding the great debate on general and specific abilities. Papers in the special issue either provided an empirical examination of the debate using a uniform dataset or they provided a debate commentary. Themes that run through the papers and that are discussed further here are that: (1) the importance of general and specific ability predictors will largely depend on the outcome to be predicted, (2) the effectiveness of both general and specific predictors will largely depend on the quality and breadth of how the manifest indicators are measured, and (3) research on general and specific ability predictors is alive and well and more research is warranted. We conclude by providing a review of potentially fruitful areas of future research.

Evolution of clinical neuropsychology: Four challenges

Quantitative and evidence-based approaches fail to capture "the whole person," neglect the important contributions of nonquantitative variables to understanding behavior, and have limitations when assessing individuals who fall outside traditional normative groups. The emphasis on quantitative and evidence-based practices is one challenge facing the profession. The lack of consensual definitions for various domains of interest is a second challenge, because it hinders research, poses communication challenges, and impedes the accumulation of knowledge about human behavior. A third challenge the profession faces is an overemphasis on the biological basis of behavior. Finally, the forth challenge is the impact of technology on practice. Since the 1970s, there has been a rapid advance in our ability to investigate the brain, resulting in a significant increase of information about brain functioning, making it difficult for clinicians to stay abreast of changes in the field. Advances in technology have resulted in "assessments" being completed by nonpsychologists. To place these and related challenges in context, a brief review of the history of assessment and efforts to investigate brain functioning will be presented. It is suggested that failure to meet these challenges will contribute to the demise of the profession. Suggestions for meeting these challenges are offered.

Association between subjective tinnitus and cognitive performance: protocol for systematic review and meta-analysis

INTRODUCTION

Subjective tinnitus is very common and has a number of comorbid associations including depression, sleep disturbance and concentration difficulties. Concentration difficulties may be observable in people with tinnitus through poorer behavioural performance in tasks thought to measure specific cognitive domains such as attention and memory (ie, cognitive performance). Several reviews have discussed the association between tinnitus and cognition; however, none to date have investigated the association between tinnitus and cognitive performance through meta-analysis with reference to an established theoretical taxonomy. Furthermore, there has been little overlap between sets of studies that have been included in previous reviews, potentially contributing to the typically mixed findings that are reported.

METHODS AND ANALYSIS

This systematic review aims to comprehensively review the literature using an established theoretical taxonomy and quantitatively synthesise relevant data to determine associations between subjective tinnitus and cognitive performance. Methods are reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols. All study designs will be eligible for inclusion with no date restrictions on searches. Studies eligible for inclusion must contain adult participants (≥18 years) with subjective tinnitus and a behavioural measure of cognitive performance. Meta-analysis will be reported via correlation for the association between tinnitus and cognitive performance.

ETHICS AND DISSEMINATION

No ethical issues are foreseen. Findings will be reported in a student thesis, at national and international , ear, nose and throat/audiology conferences and by peer-reviewed publication.

PROSPERO REGISTRATION NUMBER

CRD42018085528.

Comparing the effect of the subcategories of atypical antipsychotic medications on cognition in schizophrenia using a meta-analytic approach

OBJECTIVES

The aim of this study was to compare the two most commonly prescribed classes of atypical antipsychotic medications (i.e., -pines and -dones) with regard to their effects on cognition in patients with schizophrenia.

DATA SOURCES

Ovid Technologies web-based software was used to search the Medline and PsycINFO computerized databases to identify articles that met the inclusion criteria.

REVIEW METHODS

The search was limited to papers published after 1990, written in English, employing human subjects, using atypical antipsychotics, using a within-subjects design or control group of patients with schizophrenia for comparisons, using participants aged from 18-65, and employing standardized neuropsychological measures.

RESULTS

A total of 996 eligible studies were identified, and of these 19 were finally analyzed. Nine domains of cognitive functioning were assessed. The two groups of agents produced equivalent overall effects (-dones = .254 versus -pines = .202). The -pines were found to improve the domains of attention/working memory, executive functioning, fluency, nonverbal memory, processing speed, and verbal memory, each with a significant, small effect size. The -dones were found to improve attention/working memory, executive functioning, motor function, nonverbal memory, processing speed, and verbal memory, each with a significant, small effect size. Failsafe N was robust for all of the domains for the -pines, but only for the verbal memory domain for the -dones, suggesting that the significant findings for the other domains with the -dones are more tenuous.

CONCLUSION

The results indicate that the agents were largely equivalent and that there was no clear evidence that the pattern of cognitive effects differed as a result of the agent applied. The effects themselves, while statistically significant, were small, indicating that some or all of the differences may be attributable to practice effects on the instruments employed.

Training working memory updating in Parkinson's disease: A randomised controlled trial

Frontostriatal dysfunction in Parkinson's disease (PD) increases the risk for working memory (WM) impairment and depression, calling for counteractive measures. Computerised cognitive rehabilitation is a promising option, but targeted training protocols are lacking and lab-based training can be demanding due to the repeated visits. This study tested the feasibility and efficacy of home-based computerised training targeting mainly WM updating in PD. Fifty-two cognitively well-preserved PD patients were randomised to a WM training group and an active control group for five weeks of training (three 30-min sessions per week). WM training included three computerised adaptive WM tasks (two updating, one maintenance). The outcomes were examined pre- and post-training with trained and untrained WM tasks, tasks tapping other cognitive domains, and self-ratings of executive functioning and depression. Home-based training was feasible for the patients. The training group improved particularly on the updating training tasks, and showed posttest improvement on untrained WM tasks structurally similar to the trained ones. Moreover, their depression scores decreased compared to the controls. Our study indicates that patients with mild-to-moderate PD can self-administer home-based computerised WM training, and that they yield a similar transfer pattern to untrained WM tasks as has been observed in healthy older adults.

Meta-Analysis of the Effects of Computerized Cognitive Training on Executive Functions: a Cross-Disciplinary Taxonomy for Classifying Outcome Cognitive Factors

The growing prevalence of neurodegenerative disorders associated with aging and cognitive decline has generated increasing cross-disciplinary interest in non-pharmacological interventions, such as computerized cognitive training (CCT), which may prevent or slow cognitive decline. However, inconsistent findings across meta-analytic reviews in the field suggest a lack of cross-disciplinary consensus and on-going debate regarding the benefits of CCT. We posit that a contributing factor is the lack of a theoretically-based taxonomy of constructs and representative tasks typically used. An integration of the Cattell-Horn-Carroll (CHC) taxonomy of broad and narrow cognitive factors and the Miyake unity-diversity theory of executive functions (EF) is proposed (CHC-M) as an attempt to clarify this issue through representing and integrating the disciplines contributing to CCT research. The present study assessed the utility of this taxonomy by reanalyzing the Lampit et al. (2014) meta-analysis of CCT in healthy older adults using the CHC-M framework. Results suggest that: 1) substantively different statistical effects are observed when CHC-M is applied to the Lampit et al. meta-analytic review, leading to importantly different interpretations of the data; 2) typically-used classification practices conflate Executive Function (EF) tasks with fluid reasoning (Gf) and retrieval fluency (Gr), and Attention with sensory perception; and 3) there is theoretical and practical advantage in differentiating attention and working-memory tasks into the narrow shifting, inhibition, and updating EF domains. Implications for clinical practice, particularly for our understanding of EF are discussed.

Predictive Value of Traditional Measures of Executive Function on Broad Abilities of the Cattell–Horn–Carroll Theory of Cognitive Abilities

The neuropsychological construct of executive functions (EFs), and the psychometric Cattell–Horn–Carroll (CHC) theory of cognitive abilities are both approaches that attempt to describe cognitive functioning. The coherence between EF and CHC abilities has been mainly studied using factor-analytical techniques. Through multivariate regression analysis, the current study now assesses the integration of these latent constructs in clinical assessment. The predictive power of six widely used executive tasks on five CHC measures (crystallized and fluid intelligence, visual processing, short-term memory, and processing speed) is examined. Results indicate that executive tasks—except for the Stroop and the Tower of London—predict overall performance on the intelligence tests. Differentiation in predicting performance between the CHC abilities is limited, due to a high shared variance between these abilities. It is concluded that executive processes such as planning and inhibition have a unique variance that is not well-represented in intelligence tests. Implications for the use of EF tests and operationalization of CHC measures in clinical practice are discussed.