The use of event-related potentials in the investigation of cognitive performance in people with Multiple Sclerosis: Systematic review

A biomarker of cognition in Multiple Sclerosis (MS) that is independent from the response of people with MS (PwMS) to test questions would provide a more holistic assessment of cognitive decline. One suggested method involves event-related potentials (ERPs). This systematic review tried to answer five questions about the use of ERPs in distinguishing PwMS from controls: which stimulus modality, which experimental paradigm, which electrodes, and which ERP components are most discriminatory, and whether amplitude or latency is a better measure. Our results show larger pooled effect sizes for visual stimuli than auditory stimuli, and larger pooled effect sizes for latency measurements than amplitude measurements. We observed great heterogeneity in methods and suggest that future research would benefit from more uniformity in methods and that results should be reported for the individual subtypes of PwMS. With more standardised methods, ERPs have the potential to be developed into a clinical tool in MS.

Normative Data Estimation in Neuropsychological Tests: A Systematic Review

OBJECTIVE

To quantify the evolution, impact, and importance of normative data (ND) calculation by identifying trends in the research literature and what approaches need improvement.

METHODS

A PRISMA-guideline systematic review was performed on literature from 2000 to 2022 in PubMed, Pub-Psych, and Web of Science. Inclusion criteria included scientific articles about ND in neuropsychological tests with clear data analysis, published in any country, and written in English or Spanish. Cross-sectional and longitudinal studies were included. Bibliometric analysis was used to examine the growth, productivity, journal dispersion, and impact of the topic. VOSViewer compared keyword co-occurrence networks between 1952-1999 and 2000-2022.

RESULTS

Four hundred twelve articles met inclusion and exclusion criteria. The most studied predictors were age, education, and sex. There were a greater number of studies/projects focusing on adults than children. The Verbal Fluency Test (12.7%) was the most studied test, and the most frequently used variable selection strategy was linear regression (49.5%). Regression-based approaches were widely used, whereas the traditional approach was still used. ND were presented mostly in percentiles (44.2%). Bibliometrics showed exponential growth in publications. Three journals (2.41%) were in the Core Zone. VOSViewer results showed small nodes, long distances, and four ND-related topics from 1952 to 1999, and there were larger nodes with short connections from 2000 to 2022, indicating topic spread.

CONCLUSIONS

Future studies should be conducted on children's ND, and alternative statistical methods should be used over the widely used regression approaches to address limitations and support growth of the field.

Establishing Reference Values for a New Computerized Cognitive Function Test Program for Children

Objective

To establish reference values for the computerized cognitive test and evaluate cognitive function improvements across different age groups, we introduce the computerized Cognitive Function Test program (eCFT), specifically designed for children. We aimed to establish eCFT reference values and assess cognitive function improvements across different age groups.

Methods

We included children aged 3-6 years with confirmed normal cognition based on the Korean Developmental Screening Test for Infants and Children and Kaufman Assessment Battery for Children-II. The eCFT consists of 8 subtests for visual perception, attention, memory, and executive function.

Results

A total of 66 participants (36 males and 30 females) with an average age of 4.4 years participated. The age 6 group consistently outperformed both age group 3 and 4 in terms of correct responses. With regard to the completed stage, the "selective auditory stimulus" test findings were 2.0 and 3.9 for the age 3 and age 6 groups, respectively (p<0.05). The "trail-making" test findings were 1.7, 2.1, 2.6, and 2.8, respectively (between ages 3 and 6, p<0.01; between ages 4 and 6, p<0.05); moreover, the age 5 group surpassed the age 3 group (2.6 and 1.7, respectively, p<0.05).

Conclusion

The eCFT is an easily accessible tool to evaluate cognitive function in young children. We introduce reference values with a cutoff range for preschool-aged children, enabling early intervention for those with cognitive impairment. Given its accessibility and relatively short evaluation time, the eCFT has potential for clinical use.

Long-term cognitive and neurovascular changes after carotid endarterectomy

BACKGROUND

Carotid endarterectomy (CEA) has been associated with both cognitive decline and improvement, but the underlying neurovascular mechanisms are unclear. The aim of this study was to investigate the relationship between neurovascular indices and cognitive changes after CEA.

METHODS

We studied 55 patients with severe (≥70%) symptomatic or asymptomatic carotid stenosis before and six months after CEA. A wide array of neuropsychological tests was arranged in eight cognitive domains and cognitive functions specific to hemisphere ipsilateral to operation. Differences in cognitive performance between patients and 38 matching healthy controls were studied with linear mixed models. Neurovascular functioning and microembolic signals were assessed with transcranial Doppler ultrasound of the middle cerebral artery. Associations between neurovascular indices and cognitive change were assessed with linear regression analyses.

RESULTS

On group level, the CEA patients improved more than controls in working memory, whereas no cognitive deterioration was detected. Also on individual level, improvement was most frequently observed in working memory. Worse preoperative cerebrovascular reactivity was related with improvement in cognitive functions of the ipsilateral hemisphere. Low preoperative pulsatility index was associated with improvement in executive functioning and ipsilateral cognitive functions. Poorer preoperative blood flow velocity associated with improvement in complex attention. Microembolic signals were rare.

CONCLUSION

The present findings suggest that CEA may have beneficial long-term effects on cognition. These effects may specifically involve patients with impaired preoperative circulatory adaptive mechanisms.

Validity of the Groningen Effort Test in patients with suspected chronic solvent-induced encephalopathy

INTRODUCTION

The use of performance validity tests (PVTs) in a neuropsychological assessment to determine indications of invalid performance has been a common practice for over a decade. Most PVTs are memory-based; therefore, the Groningen Effort Test (GET), a non-memory-based PVT, has been developed.

OBJECTIVES

This study aimed to validate the GET in patients with suspected chronic solvent-induced encephalopathy (CSE) using the criterion standard of 2PVTs. A second goal was to determine diagnostic accuracy for GET.

METHOD

Sixty patients with suspected CSE referred for NPA were included. The GET was compared to the criterion standard of 2PVTs based on the Test of Memory Malingering and the Amsterdam Short Term Memory Test.

RESULTS

The frequency of invalid performance using the GET was significantly higher compared to the criterion of 2PVTs (51.7% vs. 20.0% respectively; p < 0.001). For the GET index, the sensitivity was 75% and the specificity was 54%, with a Youden's Index of 27.

CONCLUSION

The GET showed significantly more invalid performance compared to the 2PVTs criterion suggesting a high number of false positives. The general accepted minimum norm of specificity for PVTs of >90% was not met. Therefore, the GET is of limited use in clinical practice with suspected CSE patients.

Cognitive abnormalities in Becker muscular dystrophy: a mysterious link between dystrophin deficiency and executive functions

BACKGROUND

Distrophinopathies are a heterogeneous group of neuromuscular disorders due to mutations in the DMD gene. Different isoforms of dystrophin are also expressed in the cerebral cortex and Purkinje cells. Despite cognitive abnormalities in Duchenne muscular dystrophy subjects that have been described in the literature, little is known about a comprehensive cognitive profile in Becker muscular dystrophy patients.

AIM

The aim of this study was to assess cognitive functioning in Becker muscular dystrophy patients by using an extensive neuropsychological battery. Our hypothesis is that the most impaired functions are the highly intentional and conscious ones, such as working memory functions, which require a prolonged state of cellular activation.

METHODS

We performed an extensive neuropsychological assessment on 28 Becker muscular dystrophy patients from 18 to 65 years old. As control subjects, we selected 20 patients with limb-girdle muscular dystrophy, whose clinical picture was similar except for cognitive integrity. The evaluation, although extended to all areas, was focused on prefrontal control skills, with a distinction between inhibitory processes of selective attention and activating processes of working memory.

RESULTS AND CONCLUSIONS

Significant underperformances were found exclusively in the Dual Task and PASAT tests, to demonstrate a selective impairment of working memory that, while not causing intellectual disability, reduces the intellectual potential of patients with Becker muscular dystrophy.

Regional differences in field dependent-independent cognitive styles in Saudi Arabia

BACKGROUNDS

The primary aim of this study was two-fold: to assess the reliability of the Leuven Embedded Figure Test (L-EFT) in Saudi Arabia (Study 1), and to explore regional differences in independent-interdependent cognitive styles among adults in various regions of Saudi Arabia (Study 2).

METHOD

Both Study-1 and Study-2 were structured cross-sectionally. Study 1 involved 360 participants (97 % female) with a median age of 22.51 ± 3.45. Participants completed a demographic questionnaire and the L-EFT task. The mean response time for accurate responses, speed-accuracy trade-off, Cronbach's alpha reliability, Guttman split-half coefficient, and 2 × 2 ANOVA (to examine the influence of specialty and age) were evaluated using SPSS 24. In Study 2, the authors compared these evaluations between residents of Riyadh (60 participants) and Al-Kharj (60 participants) in Saudi Arabia.

RESULTS

In Study-1, the L-EFT demonstrated satisfactory psychometric properties (α = 0.79, Guttman-split-half = 0.72), with item-test correlations for all items exceeding 0.15. Study-1 found no significant impact of academic specialty on mean response time, regardless of their major (scientific studies:M = 6.68, SD = 2.54) humanities:M = 6.81, SD = 2.11). In Study 2, no significant differences were observed in mean response times between individuals residing in Riyadh and those in Al-Kharj [t(112) = 1.68, p = 0.09, 95 % CI (-0.06, 0.73)].

CONCLUSION

The scale demonstrates suitability for use in the Saudi Arabian population. However, further research is needed to compare L-EFT scores across different cultures. Moreover, future studies could also explore the influence of various socio-cultural factors on field-dependent-independent cognitive styles.

Objective evaluation of excessive daytime sleepiness

Excessive daytime sleepiness (EDS) is multifactorial. It combines, among other things, an excessive propensity to fall asleep ("physiological sleepiness") and a continuous non-imperative sleepiness (or drowsiness/hypo-arousal) leading to difficulties remaining awake and maintaining sustained attention and vigilance over the long term ("manifest sleepiness"). There is no stand-alone biological measure of EDS. EDS measures can either capture the severity of physiological sleepiness, which corresponds to the propensity to fall asleep, or the severity of manifest sleepiness, which corresponds to behavioral consequences of sleepiness and reduced vigilance. Neuropsychological tests (The psychomotor vigilance task (PVT), Oxford Sleep Resistance Test (OSLeR), Sustained Attention to Response Task (SART)) explore manifest sleepiness through several sustained attention tests but the lack of normative values and standardized protocols make the results difficult to interpret and use in clinical practice. Neurophysiological tests explore the two main aspects of EDS, i.e. the propensity to fall asleep (Multiple sleep latency test, MSLT) and the capacity to remain awake (Maintenance of wakefulness test, MWT). The MSLT and the MWT are widely used in clinical practice. The MSLT is recognized as the "gold standard" test for measuring the severity of the propensity to fall asleep and it is a diagnostic criterion for narcolepsy. The MWT measures the ability to stay awake. The MWT is not a diagnostic test as it is recommended only to evaluate the evolution of EDS and efficacy of EDS treatment. Even if some efforts to standardize the protocols for administration of these tests have been ongoing, MSLT and MWT have numerous limitations: age effect, floor or ceiling effects, binding protocol, no normal or cutoff value (or determined in small samples), and no or low test-retest values in some pathologies. Moreover, the recommended electrophysiological set-up and the determination of sleep onset using the 30‑sec epochs scoring rule show some limitations. New, more precise neurophysiological techniques should aim to detect very brief periods of physiological sleepiness and, in the future, the brain local phenomenon of sleepiness likely to underpin drowsiness, which could be called "physiological drowsiness".

Nitrogen dioxide exposure, attentional function, and working memory in children from 4 to 8 years: Periods of susceptibility from pregnancy to childhood

BACKGROUND

Air pollution exposure during pregnancy and childhood has been linked to executive function impairment in children, however, very few studies have assessed these two exposure periods jointly to identify susceptible periods of exposure. We sought to identify potential periods of susceptibility of nitrogen dioxide (NO2) exposure from conception to childhood on attentional function and working memory in school-aged children.

METHODS

Within the Spanish INMA Project, we estimated residential daily NO2 exposures during pregnancy and up to 6 years of childhood using land use regression models (n = 1,703). We assessed attentional function at 4-6 years and 6-8 years, using the Conners Kiddie Continuous Performance Test and the Attention Network Test, respectively, and working memory at 6-8 years, using the N-back task. We used distributed lag non-linear models to assess the periods of susceptibility of each outcome, adjusting for potential confounders and correcting for multiple testing. We also stratified all models by sex.

RESULTS

Higher exposure to NO2 between 1.3 and 1.6 years of age was associated with higher hit reaction time standard error (HRT-SE) (0.14 ms (95 % CI 0.05; 0.22) per 10 μg/m3 increase in NO2) and between 1.5 and 2.2 years of age with more omission errors (1.02 (95 % CI 1.01; 1.03) of the attentional function test at 4-6 years. Higher exposure to NO2 between 0.3 and 2.2 years was associated with higher HRT-SE (10.61 ms (95 % CI 3.46; 17.75) at 6-8 years only in boys. We found no associations between exposure to NO2 and working memory at 6-8 years.

CONCLUSION

Our findings suggest that NO2 exposure during the first two years of life is associated with poorer attentional function in children from 4 to 8 years of age, especially in boys. These findings highlight the importance of exploring long-term effects of traffic-related air pollution exposure in older age groups.

Performance of intraoperative neurocognitive tests during awake surgery for patients with diffuse low-grade glioma

Despite great advancements and the diffusion of awake surgery for brain tumors, the literature shows that the tests applied during the procedure are heterogeneous and non-standardized. This prospective, observational, descriptive study collected data on intraoperative brain mapping and the performance of multiple neurocognitive tests in 51 awake surgeries for diffuse low-grade glioma. Frequency of use and rate of intraoperative findings of different neurocognitive tests were analyzed. Patients mean age at the time of surgery was 35.1 (20-57) years. We performed 26 (51.0%) surgeries on the left hemisphere (LH) and 25 (49.0%) on the right hemisphere (RH). Significant differences were observed between the total number of functional findings (cortical and subcortical) identified in the LH and RH (p = 0.004). In subcortical findings alone, the differences remained significant (p = 0.0004). The RH subcortical region showed the lowest number of intraoperative findings, and this was correlated with functional outcome: Karnofsky performance scale at five days (p = 0.022), three months (p = 0.002) and one year (p = 0.002) post-surgery. On average, more tests were used to map the RH, with a lower frequency of both cortical and subcortical functional findings. Even though subcortical findings were less frequent than cortical findings, they were crucial to defining the resection margins. Based on the intraoperative findings, frequency of use, and rate of findings per use of the tests analyzed, the most relevant tests for each hemisphere for awake brain mapping were identified.

Detecting cognitive decline in high-functioning older adults: The relationship between subjective cognitive concerns, frequency of high neuropsychological test scores, and the frontoparietal control network

OBJECTIVE

Neuropsychologists have difficulty detecting cognitive decline in high-functioning older adults because greater neurological change must occur before cognitive performances are low enough to indicate decline or impairment. For high-functioning older adults, early neurological changes may correspond with subjective cognitive concerns and an absence of high scores. This study compared high-functioning older adults with and without subjective cognitive concerns, hypothesizing those with cognitive concerns would have fewer high scores on neuropsychological testing and lower frontoparietal network volume, thickness, and connectivity.

METHOD

Participants had high estimated premorbid functioning (e.g., estimated intelligence ≥75th percentile or college-educated) and were divided based on subjective cognitive concerns. Participants with cognitive concerns (n = 35; 74.0 ± 9.6 years old, 62.9% female, 94.3% White) and without cognitive concerns (n = 33; 71.2 ± 7.1 years old, 75.8% female, 100% White) completed a neuropsychological battery of memory and executive function tests and underwent structural and resting-state magnetic resonance imaging, calculating frontoparietal network volume, thickness, and connectivity.

RESULTS

Participants with and without cognitive concerns had comparable numbers of low test scores (≤16th percentile), p = .103, d = .40. Participants with cognitive concerns had fewer high scores (≥75th percentile), p = .004, d = .71, and lower mean frontoparietal network volumes (left: p = .004, d = .74; right: p = .011, d = .66) and cortical thickness (left: p = .010, d = .66; right: p = .033, d = .54), but did not differ in network connectivity.

CONCLUSIONS

Among high-functioning older adults, subjective cognitive decline may correspond with an absence of high scores on neuropsychological testing and underlying changes in the frontoparietal network that would not be detected by a traditional focus on low cognitive test scores.

Test-Retest Reliability and Reliable Change on the NIH Toolbox Cognition Battery

OBJECTIVE

Researchers and practitioners can detect cognitive improvement or decline within a single examinee by applying a reliable change methodology. This study examined reliable change through test-retest data from the English-language National Institutes of Health Toolbox Cognition Battery (NIHTB-CB) normative sample.

METHOD

Participants included adults (n = 138; age: M ± SD = 54.8 ± 20.0, range: 18-85; 51.4% men; 68.1% White) who completed test-retest assessments about a week apart on five fluid cognition tests, providing raw scores, age-adjusted standard scores (SS), and demographic-adjusted T-scores (T).

RESULTS

The Fluid Cognition Composite (SS: ICC = 0.87; T-score: ICC = 0.84) and the five fluid cognition tests had good test-retest reliability (SS: ICC range = 0.66-0.85; T-score: ICC range = 0.64-0.86). The lower and upper bounds of 70%, 80%, and 90% confidence intervals (CIs) were calculated around change scores, which serve as cutoffs for determining reliable change. Using T-scores, 90% CI, and adjustment for practice effects, 32.3% declined on one or more tests, 9.7% declined on two or more tests, 36.6% improved on one or more tests, and 5.4% improved on two or more tests.

CONCLUSIONS

It was common for participants to show reliable change on at least one test score, but not two or more test scores. Per an 80% CI, test-retest difference scores beyond these cutoffs would indicate reliable change: Dimensional Change Card Sort (SS ≥ 14/T ≥ 10), Flanker (SS ≥ 12/T ≥ 8), List Sorting (SS ≥ 14/T ≥ 10), Picture Sequence Memory (SS ≥ 19/T ≥ 13), Pattern Comparison (SS ≥ 11/T ≥ 8), and Fluid Cognition Composite (SS ≥ 10/T ≥ 7). The reliable change cutoffs could be applied in research or practice to detect within-person change in fluid cognition at the individual level.

Directed functional connectivity of the default-mode-network of young and older healthy subjects

Alterations in the default mode network (DMN) are associated with aging. We assessed age-dependent changes of DMN interactions and correlations with a battery of neuropsychological tests, to understand the differences of DMN directed connectivity between young and older subjects. Using a novel multivariate analysis method on resting-state functional MRI data from fifty young and thirty-one healthy older subjects, we calculated intra- and inter-DMN 4-nodes directed pathways. For the old subject group, we calculated the partial correlations of inter-DMN pathways with: psychomotor speed and working memory, executive function, language, long-term memory and visuospatial function. Pathways connecting the DMN with visual and limbic regions in older subjects engaged at BOLD low frequency and involved the dorsal posterior cingulate cortex (PCC), whereas in young subjects, they were at high frequency and involved the ventral PCC. Pathways combining the sensorimotor (SM) cortex and the DMN, were SM efferent in the young subjects and SM afferent in the older subjects. Most DMN efferent pathways correlated with reduced speed and working memory. We suggest that the reduced sensorimotor efferent and the increased need to control such activities, cause a higher dependency on external versus internal cues thus suggesting how physical activity might slow aging.

Performance Validity Testing on the NIH Toolbox Cognition Battery: Base Rates of Failed Embedded Validity Indicators in the Adult Normative Sample

OBJECTIVE

The goal of this study was to determine the base rates of failing proposed embedded validity indicators (EVIs) for the National Institutes of Health Toolbox Cognition Battery (NIHTB-CB) in the normative sample.

METHOD

Participants included adults in the NIHTB-CB normative sample with data to calculate age-adjusted standard scores (n = 855; ages: M(SD) = 46.9(17.3), range: 18-85; 65.0% women; education: M(SD) = 14.1(2.5) years) or demographically adjusted T-scores (n = 803; ages: M(SD) = 47.3(17.3), range: 18-85; 65.3% women; education: M(SD) = 14.2(2.5) years) for all tests. The NIHTB-CB includes two tests of crystallized cognition and five tests of fluid cognition. Individual norm-referenced test performances were categorized as falling above or below liberal and conservative cutoffs based on proposed univariate EVIs. The number of univariate EVI failures was summed to compute multivariable EVIs. EVI failure rates above 10% were considered high false-positive rates, indicating specificity < .90. Using chi-square analyses, the frequencies of EVI failures were compared based on gender, race/ethnicity, education, and crystallized composite.

RESULTS

The multivariable EVIs had predominantly low false-positive rates in the normative sample. EVI failure rates were most common among participants with low crystallized composites. Using age-adjusted standard scores, EVI failure rates varied by education, race/ethnicity, and estimated premorbid intelligence. These differences were mostly eliminated when using demographically adjusted T-scores.

CONCLUSIONS

Multivariable EVIs requiring ≥ 4 failures using liberal cutoffs or ≥ 3 failures using conservative cutoffs had acceptable false-positive rates (i.e., < 10%) using both age-adjusted standard scores and demographically adjusted T-scores. These multivariable EVIs could be applied to large data sets with NIHTB-CB data to screen for potentially invalid test performances.

Effect of remote ischemic preconditioning on postoperative cognitive dysfunction in adult patients with general anesthesia: a meta-analysis

BACKGROUND

Remote ischemic preconditioning (RIPC) is proven to have neuroprotective protective effects. Nevertheless, the impact of RIPC on postoperative cognitive dysfunction (POCD) in patients undergoing general anesthesia is controversial. This meta-analysis of randomized controlled trials (RCTs) aimed to assess the effect of RIPC on POCD in adults after general anesthesia.

METHODS

Relevant literature was obtained by searching Embase, PubMed, Web of Science, Cochrane Library, Wanfang, and China National Knowledge Infrastructure (CNKI) databases in July 2022. RCTs were included to assess the influences of RIPC on POCD in adults following general anesthesia. Two investigators independently performed literature screening, data extraction, and quality assessment based on the inclusion and exclusion criteria. The incidence of POCD, operation time, and hospital stay were analyzed by Review manager5.4 software.

RESULTS

Thirteen RCTs with 1122 participants were selected for this meta-analysis. Compared to the control group, RIPC decreased the incidence of POCD (OR = 0.50, 95% CI 0.31-0.82), as well as reduced the duration of hospitalization (MD = - 0.98, 95% CI - 1.69 to - 0.27), but did not prolong operative time (MD = - 2.65, 95% CI - 7.68 to 2.37).

CONCLUSION

RIPC reduced the incidence of POCD in adult patients after general anesthesia and accelerated their discharge.

Unveiling the sound of the cognitive status: Machine Learning-based speech analysis in the Alzheimer's disease spectrum

BACKGROUND

Advancement in screening tools accessible to the general population for the early detection of Alzheimer's disease (AD) and prediction of its progression is essential for achieving timely therapeutic interventions and conducting decentralized clinical trials. This study delves into the application of Machine Learning (ML) techniques by leveraging paralinguistic features extracted directly from a brief spontaneous speech (SS) protocol. We aimed to explore the capability of ML techniques to discriminate between different degrees of cognitive impairment based on SS. Furthermore, for the first time, this study investigates the relationship between paralinguistic features from SS and cognitive function within the AD spectrum.

METHODS

Physical-acoustic features were extracted from voice recordings of patients evaluated in a memory unit who underwent a SS protocol. We implemented several ML models evaluated via cross-validation to identify individuals without cognitive impairment (subjective cognitive decline, SCD), with mild cognitive impairment (MCI), and with dementia due to AD (ADD). In addition, we established models capable of predicting cognitive domain performance based on a comprehensive neuropsychological battery from Fundació Ace (NBACE) using SS-derived information.

RESULTS

The results of this study showed that, based on a paralinguistic analysis of sound, it is possible to identify individuals with ADD (F1 = 0.92) and MCI (F1 = 0.84). Furthermore, our models, based on physical acoustic information, exhibited correlations greater than 0.5 for predicting the cognitive domains of attention, memory, executive functions, language, and visuospatial ability.

CONCLUSIONS

In this study, we show the potential of a brief and cost-effective SS protocol in distinguishing between different degrees of cognitive impairment and forecasting performance in cognitive domains commonly affected within the AD spectrum. Our results demonstrate a high correspondence with protocols traditionally used to assess cognitive function. Overall, it opens up novel prospects for developing screening tools and remote disease monitoring.

Acute effects of a chewable beetroot-based supplement on cognitive performance: a double-blind randomized placebo-controlled crossover clinical trial

BACKGROUND

Dietary nitrate (NO3-) has been shown to be useful as an ergogenic aid with potential applications in health and disease (e.g., blood pressure control). However, there is no consensus about the effects of dietary NO3- or beetroot (BR) juice supplementation on cognitive function.

OBJECTIVE

The aim of this study was to evaluate the effects of a single dose of a chewable BR-based supplement on cognitive performance.

METHODS

A double-blind randomized placebo-controlled two-period crossover clinical trial was carried out based on the extension of the CONSORT guidelines for randomized crossover trials. A total of 44 participants (24 F; 20 M; 32.7 [12.5] years; 66.3 [9.0] kg; 170 [9.2] cm; 22.8 [1.4] kg/m2) were randomly allocated to receive first either four BR-based chewable tablets (BR-CT) containing 3 g of a Beta vulgaris extract (RedNite®) or four tablets of a placebo (maltodextrin). A 4-day washout period was used before crossover. Ninety minutes after ingestion of the treatments, a neuropsychological testing battery was administered in each period. The trial was registered at clinicaltrials.gov NCT05509075.

RESULTS

Significant improvements with moderate effect size were found on memory consolidation at the short and long term only after BR-CT supplementation via the Rey Auditory Verbal Learning Test immediate (+ 20.69%) and delayed (+ 12.34%) recalls. Likewise, enhancement on both frontal lobe functions (+ 2.57%) and cognitive flexibility (+ 11.16%) were detected after BR-CT. There was no significant change (p < 0.05) on verbal memory of short-term digits, working memory and information processing speed. Mixed results were found on mood and anxiety through the Beck Depression Inventory-II (BDI-II) and the State-Trait Anxiety Inventory (STAI-Y1 and STAI-Y2); however, sequence and period effects were seen on STAI-Y2.

CONCLUSIONS

The acute administration of a chewable BR-based supplement improves certain aspects of cognitive function in healthy females and males, particularly memory capacity and frontal skills.

Disruption of the serial position effect as an early marker of Alzheimer's disease in Spanish-English bilinguals

OBJECTIVES

The present study examined if disruption of serial position effects in list recall could serve as an early marker of Alzheimer's disease (AD) in Spanish-English bilinguals.

METHODS

We tested 20 participants initially diagnosed as cognitively normal or with mild cognitive impairment who declined and eventually received a diagnosis of AD (decliners), and 37 who remained cognitively stable (controls) over at least 2 years. Participants were tested on the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Word List Learning Test in English or Spanish as part of an annual neuropsychological evaluation.

RESULTS

Compared to controls, decliners exhibited significantly reduced recall including reduced primacy scores (i.e., items recalled from the first three list items on Trial 1), whereas recency scores (i.e., items recalled from the last 3 list items on Trial 1) were equivalent in decliners and controls. Further analyses suggested that the sensitivity of the primacy effect to preclinical AD was initially stronger in participants tested in Spanish, a surprising finding given that the CERAD was developed for English speakers. However, in the subsequent year of testing, primacy scores declined to the same level regardless of language of testing.

CONCLUSIONS

Several list learning measures may facilitate early diagnosis of AD in Spanish-English bilinguals, possibly including the relatively understudied primacy effect. Additional studies are needed to investigate the possibility that linguistic or demographic variables might modulate sensitivity of list learning tests to preclinical AD, which could lead to broader improvements in their utility for early diagnosis of AD in all populations.

Resting-state functional connectivity and cognitive performance in aging adults with cognitive decline: A data-driven multivariate pattern analysis

BACKGROUND

Cognitive impairments occur on a continuous spectrum in multiple cognitive domains showing individual variability of the deteriorating patterns; however, often, cognitive domains are studied separately.

METHODS

The present study investigated aging individual variations of cognitive abilities and related resting-state functional connectivity (rsFC) using data-driven approach. Cognitive and neuroimaging data were obtained from 62 elderly outpatients with cognitive decline. Principal component analysis (PCA) was conducted on the cognitive data to determine patterns of cognitive performance, then data-driven whole-brain connectome multivariate pattern analysis (MVPA) was applied on the neuroimaging data to discover neural regions associated with the cognitive characteristic.

RESULTS

The first component (PC1) delineated an overall decline in all domains of cognition, and the second component (PC2) represented a compensatory relationship within basic cognitive functions. MVPA indicated rsFC of the cerebellum lobule VIII and insula with the default-mode network, frontoparietal network, and salience network inversely correlated with PC1 scores. Additionally, PC2 score was related to rsFC patterns with temporal pole and occipital cortex.

CONCLUSIONS

The featured primary cognitive characteristic depicted the importance of the cerebellum and insula connectivity patterns in of the general cognitive decline. The findings also discovered a secondary characteristic that communicated impaired interactions within the basic cognitive function, which was independent from the impairment severity.

3-Year test-retest reliability in Parkinson's disease and healthy older adults: The Parkinson's progression markers initiative study

Repeated neuropsychological assessments are often conducted in clinical and research settings to track cognitive changes over single or multiple intervals in patients with Parkinson's disease (PD). Yet few studies have documented test-retest reliability in PD. To address this gap, we used data from the Parkinson's Progression Markers Initiative (PPMI) to investigate the reliability of five well-known neuropsychological tests over a 3-year follow-up assessment in early-stage PD with either normal (PD-NC; N = 158) or abnormal (PD-AC; N = 39) cognitive screening, categorized based on recommended cutoffs for the Montreal Cognitive Assessment (MoCA), and healthy older adults (HOA; N = 102). All participants analyzed maintained the same cognitive status category across the assessment points. Intraclass correlation coefficients (ICCs) estimated reliability. The overall ICCs calculated across time points were as follows: Judgment of Line Orientation (PD-NC = .47, PD-AC = .50, HOA = .59); Letter-Number Sequencing (PD-NC = .64, PD-AC = .64, HOA = .65); Semantic Fluency (PD-NC = .69, PD-AC = .89, HOA = .77); Symbol Digit Modalities Test (PD-NC = .67, PD-AC = .83, HOA = .71). For the two primary components of the Hopkins Verbal Learning Test-Revised, we found the following ICCs: immediate recall (PD-NC = .46, PD-AC = .57, HOA = .58); delayed recall (PD-NC = .42, PD-AC = .57, HOA = .54). Findings from this study provide useful information for clinicians and researchers toward selecting suitable neuropsychological tests to monitor cognition at two or more time points among newly diagnosed individuals with PD and HOA.

APOE ε4 positivity predicts centrality of episodic memory nodes in patients with mild cognitive impairment: A cohort-based, graph theory-informed study of cognitive networks

As network neuroscience can capture the systemic impact of APOE variability at a neuroimaging level, this study investigated the network-based cognitive endophenotypes of ε4-carriers and non-carriers across the continuum between normal ageing and Alzheimer's dementia (AD). We hypothesised that the impact of APOE-ε4 on cognitive functioning can be reliably captured by the measurement of graph-theory centrality. Cognitive networks were calculated in 8118 controls, 3482 MCI patients and 4573 AD patients, recruited in the National Alzheimer's Coordinating Center (NACC) database. Nodal centrality was selected as the neurofunctional readout of interest. ε4-carrier-vs.-non-carrier differences were tested in two independent NACC sub-cohorts assessed with either Version 1 or Version 2 of the Uniform Data Set neuropsychological battery. A significant APOE-dependent effect emerged from the analysis of the Logical-Memory nodes in MCI patients in both sub-cohorts. While non-carriers showed equal centrality in immediate and delayed recall, the latter was significantly less central among carriers (v1: bootstrapped confidence interval 0.107-0.667, p < 0.001; v2: bootstrapped confidence interval 0.018-0.432, p < 0.001). This indicates that, in carriers, delayed recall was, overall, significantly more weakly correlated with the other cognitive scores. These findings were replicated in the sub-groups of sole amnestic-MCI patients (n = 2971), were independent of differences in network communities, clinical severity or other demographic factors. No effects were found in the other two diagnostic groups. APOE-ε4 influences nodal properties of cognitive networks when patients are clinically classified as MCI. This highlights the importance of characterising the impact of risk factors on the wider cognitive network via network-neuroscience methodologies.

Effects of sociodemographic and player characteristics on baseline cognitive performance in 1000 rugby players: A retrospective 8-year follow-up study

OBJECTIVES

To analyze the effects of sociodemographic and player characteristics on the Sport Concussion Assessment Tool and neuropsychological scores over 8 years in a large sample of rugby players.

DESIGN

An 8-year retrospective study of preseason clinical assessments of professional rugby players and players enrolled in training academies at professional clubs.

METHODS

The Sport Concussion Assessment Tool-3 or -5, Trail Making Test and Digit Symbol Substitution Test were administered prior to the start of the competition season for each player. Statistical analyses included: (i) descriptive analyses of sociodemographic, player and neuropsychological characteristics; (ii) multivariate models to identify factors influencing cognitive scores at the first visit; and (iii) linear mixed models to assess the evolution of the scores over the years.

RESULTS

One thousand players were included (mean age: 22.8, males: 92 %). Twenty-two percent of the athletes reported baseline symptoms. A higher level of education was associated with better cognitive scores at the first visit and over the years. Forwards had poorer processing speed performances compared to backs at the first visit and over repeated assessments. Finally, the number of examinations was associated with improved cognitive scores showing a practice effect on all the neuropsychological tests, except for the Standardized Assessment of Concussion 5th edition.

CONCLUSIONS

Results from this retrospective study could help to improve the management of athletes and return-to-play decision-making in collision sports.

Comparative analysis of anticholinergic burden scales to explain iatrogenic cognitive impairment and self-reported side effects in the euthymic phase of bipolar disorders: Results from the FACE-BD cohort

Bipolar disorders (BD) are characterized by cognitive impairment during the euthymic phase, to which treatments can contribute. The anticholinergic properties of medications, i.e., the ability of a treatment to inhibit cholinergic receptors, are associated with cognitive impairment in elderly patients and people with schizophrenia but this association has not been well characterized in individuals with remitted BD. Moreover, the validity of only one anticholinergic burden scale designed to assess the anticholinergic load of medications has been tested in BD. In a literature review, we identified 31 existing scales. We first measured the associations between 27 out of the 31 scales and objective cognitive impairment in bivariable regressions. We then adjusted the bivariable models with covariates: the scales significantly associated with cognitive impairment in bivariable and multiple logistic regressions were defined as having good concurrent validity to assess cognitive impairment. In a sample of 2,031 individuals with euthymic BD evaluated with a neuropsychological battery, two scales had good concurrent validity to assess cognitive impairment, whereas chlorpromazine equivalents, lorazepam equivalents, the number of antipsychotics, or the number of treatments had not. Finally, similar analyses with subjective anticholinergic side-effects as outcome variables reported 14 scales with good concurrent validity to assess self-reported peripheral anticholinergic side-effects and 13 to assess self-reported central anticholinergic side-effects. Thus, we identified valid scales to monitor the anticholinergic burden in BD, which may be useful in estimating iatrogenic cognitive impairment in studies investigating cognition in BD.

Cardiac output, cerebral blood flow and cognition in patients with severe aortic valve stenosis undergoing transcatheter aortic valve implantation: design and rationale of the CAPITA study

BACKGROUND

Approximately one-third of patients with symptomatic severe aortic valve stenosis who are scheduled for transcatheter aortic valve implantation (TAVI) have some degree of cognitive impairment. TAVI may have negative cognitive effects due to periprocedural micro-emboli inducing cerebral infarction. On the contrary, TAVI may also have positive cognitive effects due to increases in cardiac output and cerebral blood flow (CBF). However, studies that systematically assess these effects are scarce. Therefore, the main aim of this study is to assess cerebral and cognitive outcomes in patients with severe aortic valve stenosis undergoing TAVI.

STUDY DESIGN

In the prospective CAPITA (CArdiac OutPut, Cerebral Blood Flow and Cognition In Patients With Severe Aortic Valve Stenosis Undergoing Transcatheter Aortic Valve Implantation) study, cerebral and cognitive outcomes are assessed in patients undergoing TAVI. One day before and 3 months after TAVI, patients will undergo echocardiography (cardiac output, valve function), brain magnetic resonance imaging (CBF, structural lesions) and extensive neuropsychological assessment. To assess longer-term effects of TAVI, patients will again undergo echocardiography and neuropsychological assessment 1 year after the procedure. The co-primary outcome measures are change in CBF (in ml/100 g per min) and change in global cognitive functioning (Z-score) between baseline and 3‑month follow-up. Secondary objectives include change in cardiac output, white matter hyperintensities and other structural brain lesions. (ClinicalTrials.gov identifier NCT05481008) CONCLUSION : The CAPITA study is the first study designed to systematically assess positive and negative cerebral and cognitive outcomes after TAVI. We hypothesise that TAVI improves cardiac output, CBF and cognitive functioning.

Cognitive Functioning of Unaffected First-degree Relatives of Individuals With Late-onset Alzheimer's Disease: A Systematic Literature Review and Meta-analysis

First-degree relatives of individuals with late-onset Alzheimer's disease (LOAD) are at increased risk for developing dementia, yet the associations between family history of LOAD and cognitive dysfunction remain unclear. In this quantitative review, we provide the first meta-analysis on the cognitive profile of unaffected first-degree blood relatives of LOAD-affected individuals compared to controls without a family history of LOAD. A systematic literature search was conducted in PsycINFO, PubMed /MEDLINE, and Scopus. We fitted a three-level structural equation modeling meta-analysis to control for non-independent effect sizes. Heterogeneity and risk of publication bias were also investigated. Thirty-four studies enabled us to estimate 218 effect sizes across several cognitive domains. Overall, first-degree relatives (n = 4,086, mean age = 57.40, SD = 4.71) showed significantly inferior cognitive performance (Hedges' g = -0.16; 95% CI, -0.25 to -0.08; p < .001) compared to controls (n = 2,388, mean age = 58.43, SD = 5.69). Specifically, controls outperformed first-degree relatives in language, visuospatial and verbal long-term memory, executive functions, verbal short-term memory, and verbal IQ. Among the first-degree relatives, APOE ɛ4 carriership was associated with more significant dysfunction in cognition (g = -0.24; 95% CI, -0.38 to -0.11; p < .001) compared to non-carriers (g = -0.14; 95% CI, -0.28 to -0.01; p = .04). Cognitive test type was significantly associated with between-group differences, accounting for 65% (R23 = .6499) of the effect size heterogeneity in the fitted regression model. No evidence of publication bias was found. The current findings provide support for mild but robust cognitive dysfunction in first-degree relatives of LOAD-affected individuals that appears to be moderated by cognitive domain, cognitive test type, and APOE ɛ4.

An Evaluation of Cross-Cultural Adaptations of Social Cognition Testing: A Systematic Review

Social cognition remains one of the most difficult cognitive domains to assess in diverse populations due to a lack of culturally appropriate tools. This study systematically reviewed literature on neuropsychological tests for social cognition that have been translated, adapted, are cross-cultural, or are assembled for diverse, specifically "Global South," populations. The aim was to identify assessments appropriate for diverse populations, outline and evaluate their methodological approaches, and provide procedural recommendations for future research. The PRISMA systematic review search strategy produced 10,957 articles, of which 287 were selected for full-text screening. The study had to include a neuropsychological assessment of social cognition. The full text of the resulting 287 articles was then screened; the study had to include a translated, adapted, cross-cultural test, or an assembled test for Global South populations. Eighty-four articles were included in this study: 24 for emotion recognition, 45 for theory of mind, 9 for moral reasoning, and six for social cognition in general. Overall, there were 31 translations, 27 adaptations, 14 cross-cultural tests, and 12 assembled tests for Global South populations. Regarding quality, 35 were of low quality, 27 were of moderate quality, and 22 were high quality. This study provides an overview of social cognition tests modified or assembled for diverse populations and gives examples of methodological procedures. It highlights the variability in procedure quality and provides possible reasons for this variability. Finally, it suggests a need to report rigorous modification and assembly procedure in order to have modified and assembled social cognition tests appropriate for diverse populations.

Regression-based normative data for the D-KEFS Color-Word Interference Test in Norwegian adults ages 20-85

Objective: The Delis-Kaplan Executive Function System (D-KEFS) Color-Word-Interference Test (CWIT; AKA Stroop test) is a widely used measure of processing speed and executive function. While test materials and instructions have been translated to Norwegian, only American age-adjusted norms from D-KEFS are available in Norway. We here develop norms in a sample of 1011 Norwegians between 20 and 85 years. We provide indexes for stability over time and assess demographic adjustments applying the D-KEFS norms. Method: Participants were healthy Norwegian adults from Center for Lifespan Changes in Brain and Cognition (LCBC) (n = 899), the Dementia Disease Initiation (n = 77), and Oslo MCI (n = 35). Using regression-based norming, we estimated linear and non-linear effects of age, education, and sex on the CWIT 1-4 subtests. Stability over time was assessed with intraclass correlation coefficients (ICC). The normative adjustment of the D-KEFS norms was assessed with linear regression models. Results: Increasing age was associated with slower completion on all CWIT subtests in a non-linear fashion (accelerated lowering of performance with older age). Women performed better on CWIT-1&3. Higher education predicted faster completion time on CWIT-3&4. The original age-adjusted norms from D-KEFS did not adjust for sex or education. Furthermore, we observed significant, albeit small effects of age on all CWIT subtests. ICC analyses indicated moderate to good stability over time. Conclusion: We present demographically adjusted regression-based norms and stability indexes for the D-KEFS CWIT subtests. US D-KEFS norms may be inaccurate for Norwegians with high or low educational attainment, especially women.

Clarifying the link between psychopathologies and heart rate variability, and the sex differences: Can neuropsychological features serve as mediators?

BACKGROUND

Patients with common mental disorders (depression, anxiety, and somatic symptoms) often exhibit lower heart rate variability (HRV) than healthy individuals. Under the hypothesis that disorder status affects cognitive function, we examined whether neuropsychological features can be mediators between psychopathologies and HRV and possible sex differences.

METHODS

We recruited 359 individuals (aged 42.47 ± 12.23) with and without common mental disorders. Questionnaires were used to measure their psychopathologies. Eight tests from the Cambridge Neuropsychological Test Automated Battery were selected to measure neuropsychological functions. Resting-state HRV measurements were obtained for 5 min. The associations among these constructs were analyzed using multiple linear regression analysis and structural equation modelling.

RESULTS

Among women, Reaction Time (RTI, a task of psychomotor speed) indicator mediated the relationship between depression and low-frequency power (LF); Emotion Recognition Task (ERT, a task of emotional regulation) indicator mediated the relationship between health anxiety and high-frequency power (HF). Among men, Intra-Extra Dimensional Set Shift (IED, a task of shifting) indicator mediated the relationship between depression and LF; Match to Sample Visual Search (MTS, a task of selective attention) indicator mediated the relationship between health cognition and HF. The depression-RTI-LF pathway in women tended to lower HRV; whereas health anxiety-ERT-HF in women, depression-IED-LF and health cognition-MTS-HF in men tended to increase HRV.

LIMITATIONS

Possible medication effects; not directly measuring brain activity; only gathering resting-state HRV.

CONCLUSION

Our findings support the notion that neuropsychological features mediate the relationship between psychopathologies and HRV, and that sex differences exist.

Bayesian estimation for the accuracy of three neuropsychological tests in detecting Alzheimer's disease and mild cognitive impairment: a retrospective analysis of the ADNI database

BACKGROUND

The neuropathological confirmation serves as the gold standard for diagnosing Alzheimer's disease (AD), but it is usually not available to the living individuals. In addition, the gold standard for diagnosing Mild Cognitive Impairment (MCI) remains unclear yet. Neuropsychological testing, such as the Montreal Cognitive Assessment (MoCA), Mini-Mental State Examination (MMSE) and Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-cog), is commonly used tests in identifying AD and MCI, offering convenience, affordability, non-invasiveness, and accessibility in clinical settings. We aimed to accurately evaluate the discriminative ability of the three tests administrated at the same visit simultaneously in detecting AD and MCI due to AD in the absence of a gold standard.

METHODS

A total of 1289 participants aged over 65 were included from the baseline visits of Alzheimer's disease Neuroimaging Initiative. Bayesian latent class models, accounting for conditional dependence between MoCA and MMSE, were conducted to assess the diagnostic accuracy of the three tests for detecting AD and MCI.

RESULTS

In detecting AD, the ADAS-cog had the highest Youden's Index (0.829), followed by the MoCA(0.813) and MMSE(0.796). The ADAS-cog and MoCA showed similar sensitivity (0.922 vs 0.912) and specificity (0.907 vs 0.901), while the MMSE had lower sensitivity (0.874) and higher specificity (0.922). For MCI detection, the ADAS-cog had the highest Youden's Index (0.704) compared to the MoCA (0.614) and MMSE (0.478). The ADAS-cog exhibited the highest sensitivity, closely followed by the MoCA and MMSE (0.869 vs 0.845 vs 0.757), and the ADAS-cog also had good specificity (0.835 vs 0.769 vs 0.721). The estimated true prevalence of AD among individuals aged over 65 was 20.0%, and the estimated true prevalence of MCI due to AD was 24.8%.

CONCLUSIONS

The findings suggest that the ADAS-cog and MoCA are reliable tools for detecting AD and MCI, while the MMSE may be less sensitive in detecting these conditions. A large underdiagnosis of the MCI and Alzheimer's population still remains in clinical screening.

Learning potential and visuospatial memory could predict amyloid-beta positron emission tomography positivity in amnestic mild cognitive impairment

We investigate the role of neuropsychological tests, including the learning potential, in predicting amyloid-beta positron emission tomography (Aβ-PET) status in amnestic mild cognitive impairment (aMCI). This cross-sectional study included 64 patients with aMCI (31 Aβ-PET (-) and 33 (+)) who visited a memory impairment clinic at Pusan National University Hospital between 2014 and 2019. Patients underwent Aβ-PET scans using 18F-florbetaben and the Seoul Neuropsychological Screening Battery. Learning potential was determined based on the difference in scores between the first and third trials of the Seoul Verbal Learning test (SVLT). Binary logistic regression was used to demonstrate the association between Aβ-PET status and cognitive tests. Predictive ability of cognitive tests for Aβ deposition was investigated using receiver operating characteristic curves analysis. From logistic regression models, the SVLT learning potential and Rey-Osterrieth Complex Figure Test (RCFT) delayed recall were found to predict Aβ-PET positivity. The areas under the curve (AUC) of the SVLT learning potential and RCFT delayed recall were significantly different from 0.5. Our findings of an association between Aβ deposition status and learning potential and visuospatial memory suggest that these cognitive tests could be used to screen patients with aMCI for Aβ deposition status.

Normative Data for the Judgment of Line Orientation Test (Long and Short Forms) in the Quebec-French Population Aged between 50 and 89 Years

The Judgment of Line Orientation (JLO) Test of Benton assesses visuospatial processing without requiring motor skills. The test is frequently used in geriatric or brain-injured populations. As with other cognitive tests, performance on the JLO test may vary according to age, level of education, sex, and cultural background of individuals. The present study aimed to establish normative data for a short (15 items) and a long (30 items) form of the JLO. The sample for the short and long forms comprised 198 and 260 individuals, respectively, aged 50-89 years. All participants were French-speaking people from the province of Quebec, Canada. Using regression-based norming, the effects of age, years of formal education, and sex on JLO performance were estimated. The normative adjustment of the JLO short and long forms considered the weight of each predictor on test performance. Results indicated that JLO performance was positively associated with years of formal education and male sex, whereas it was negatively associated with age. Accordingly, normative data were generated using Z-scores and adjusted scaled scores derived from the regression equations. To conclude, the present norms will ease the detection of visuospatial impairment in French-Quebec middle-aged and older adults.

A validation study for wide-range remote assessment of cognitive functions in the healthy older Japanese population: a pilot randomised crossover trial

BACKGROUND

The assessment of a wide range of cognitive functions using video teleconference (VTC) systems cannot be applied in practice yet. We aimed to determine the feasibility and reliability of previously unvalidated remote cognitive function tests in Japan using common information and communication technology (ICT) devices, software, and VTC systems compared with face-to-face (FTF) assessment.

METHODS

The sample consisted of 26 participants from senior citizens clubs and an employment service centre in Sapporo Japan, including 11 females and 15 males (age averaged 78.6 ± 6.8 years). Tests included the RCPM, Story recall, 10/36 spatial recall, selective reminding test, SDMT, PASAT, FAB, TMT-A, TMT-B, visual cancellation task, digit span, tapping span. The experimental design was a counterbalanced crossover randomised controlled trial. Intraclass correlations (ICCs), paired-samples t-tests, Cohen's Kappa (κ) coefficients, and Wilcoxon signed-rank test were calculated to compare the scores between VTC and FTF assessments.

RESULTS

All ICCs were significant and ranged from 0.47 (RCPM time) to 0.92 (RCPM score and PASAT), with a mean ICC of 0.75. Digit span using Cohen's Kappa (κ) coefficient was significant, but the tapping span was not. Paired samples t-test showed statistically significant differences in SDMT, RCPM time, and cancellation time.

CONCLUSIONS

The results suggest that remote video conference-based neuropsychological tests even using familiar devices and software may be able to assess a wide range of cognitive functions in the Japanese older population. As for the processing speed tasks, we need to create our own standards for the remote condition. For the tapping span, we should consider increasing the number of trials.

Late-onset epilepsy with cognitive symptoms: Comparison of cognitive and imaging profiles with probable Alzheimer's disease

OBJECTIVE

We aimed to (i) compare the clinical, neuropsychological, and neuroimaging characteristics of unprovoked late-onset epilepsy (LOE) patients with cognitive symptoms against probable Alzheimer's disease (AD) patients; (ii) clarify how neurodegeneration and other processes could be implicated in the cognitive symptoms of unprovoked LOE patients; and (iii) characterize the longitudinal trajectory of unprovoked LOE patients with cognitive symptoms.

METHODS

Twenty-six unprovoked LOE patients with cognitive symptoms and 26 probable AD were retrospectively recruited from epilepsy and memory clinics at a single tertiary referral center. The patients underwent comprehensive clinical, neuropsychological, and 18Fluorodeoxyglucose PET-CT assessments. All LOE patients had clinical follow-up and a subset of 17 patients had repeat neuropsychological assessments.

RESULTS

At baseline, 18% of LOE patients with cognitive symptoms had dementia-range cognitive impairment and one received a diagnosis of probable AD. Compared with the probable AD group, the LOE group did not perform significantly better in global measures of cognition (total ACE-III), neuropsychological tests for fluency, working memory, language, attention, or executive function, but performed better in naming, memory, and visuospatial ability. The commonest patterns of cognitive impairment in the LOE group were frontal and left temporal, whereas all AD patients exhibited parietotemporal patterns. The AD group had more 18Fluorodeoxyglucose PET-CT hypometabolism in the parietal and occipital, but not the temporal and frontal lobes. During the 3.0 ± 3.2 years follow-up, improved seizure frequency in the LOE group covaried with improved total ACE-III score, there was no further conversion to probable AD and no group-level cognitive decline.

CONCLUSION

Unprovoked LOE patients with cognitive symptoms had varying severities of cognitive impairment, and different patterns of cognitive and imaging abnormalities compared with AD patients. They were rarely diagnosed with probable AD at presentation or follow-up. Cognitive outcome in LOE may be related to seizure control. Cerebral small vessel disease may play a role in LOE-associated cognitive impairment.

Decrease in cognitive performance and increase of the neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios with higher doses of antipsychotics in women with schizophrenia: a cross-sectional study

BACKGROUND

We explored the relationship between symptoms, cognitive performance, neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR) (three markers of inflammation), and antipsychotic dose (in chlorpromazine units) in male and female patients with schizophrenia.

METHODS

We conducted a cross-sectional analysis in patients with schizophrenia of the complete blood count and the results of neuropsychological testing, using the Welch t-test to compare groups and the Pearson test for correlations.

RESULTS

We found that the NLR and the PLR are higher among women with schizophrenia when compared with men. In women, the NLR and the PLR correlate positively with antipsychotic drug dose and inversely with a working memory test (Direct Digit Span). Higher doses of antipsychotics are associated with worse working and semantic memory and mental flexibility in the women in our sample.

CONCLUSION

Higher doses of antipsychotics were associated with worse working and semantic memory and mental flexibility in women with schizophrenia. No such correlations were present in men, suggesting that, in female patients, cognitive performance deteriorates as the antipsychotic dose is increased, a finding that could be mediated by inflammatory mechanisms, given the demonstrated relationship to biomarkers of inflammation - e.g., the NLR and the PLR.

TRIAL REGISTRATION

NCT03788759 (ClinicalTrials.gov).

Neuropsychological domains and fitness to drive in mild cognitive impairment or Alzheimer's disease

Cognitive deficits associated with mild cognitive impairment (MCI) or Alzheimer's disease (AD) can impact driving. This integrative review investigated which cognitive domains were associated with poor driving performance or unfitness to drive in studies with outcomes measured in simulator or on-road driving in patients with MCI or AD. The review was conducted by searching for articles published between 2001 and 2020 in the MEDLINE (via PubMed), EMBASE, and SCOPUS databases. Studies addressing patients with other dementias (e.g., vascular or mixed dementia, Lewy body dementia, Parkinson's disease) were excluded. Of 404 articles initially selected, 17 met the eligibility criteria for this review. Based on the findings of this integrative review, attentional capacity, processing speed, executive functions and visuospatial skills were the functions whose declines were most frequently reported in a context of unsafe driving by older adults with MCI or AD. Reports were remarkably heterogeneous in methodological aspects whereas quite limited in cross-cultural coverage and in sample recruited, what prompts for further trials in the field.

Teleneuropsychology for vascular cognitive impairment: Which tools do we have?

The halt of clinical activities imposed during the COVID-19 pandemic forced clinicians to find alternative strategies to provide continuity of care and services, and led to a renewed interest in use of teleneuropsychology (TNP) to remotely assess patients. Recent TNP guidelines recommend maximizing the reproduction of standard in-person assessment, particularly through videoconferences. However, consistency of the adaptations of usual cognitive tests to videoconference needs further elucidation. This review aims at critical reviewing which cognitive tests could be recommended for a remote evaluation of patients with vascular cognitive impairment (VCI) among those widely recognized as reference standards. Current evidence supports the use of global cognitive efficiency (MMSE and MoCA), verbal memory (Revised Hopkins Verbal Learning Test), and language tests (phonemic and semantic verbal fluencies, Boston Naming Test), while there is a lack of strong validity support for measures of visuospatial functions (Rey-Osterreith Complex Figure), and executive functioning and processing speed (Trail making Test, and Digit symbol or Symbol digit tests). This represents a major limitation in the evaluation of VCI because its cognitive profile in often characterized by attention and executive deficits. At present, a videoconference TNP visit appears useful for a brief evaluation of global cognitive efficiency, and to 'triage' patients towards a second level in person evaluation. In future, hybrid models of TNP based on data collected across multiple modalities, incorporating both adaptation of usual cognitive tools and new computerized tools in the supervised videoconference setting, are likely to become the best option for a comprehensive remote cognitive assessment.

Predictors of within-individual variability in cognitive performance in schizophrenia in a South African case-control study

INTRODUCTION

Cognitive dysfunction in schizophrenia may be assessed by measuring within-individual variability (WIV) in performance across a range of cognitive tests. Previous studies have found increased WIV in people with schizophrenia, but no studies have been conducted in low- to middle-income countries where the different sociocultural context may affect WIV. We sought to address this gap by exploring the relationship between WIV and a range of clinical and demographic variables in a large study of people with schizophrenia and matched controls in South Africa.

METHODS

544 people with schizophrenia and 861 matched controls completed an adapted version of The University of Pennsylvania Computerized Neurocognitive Battery (PennCNB). Demographic and clinical information was collected using the Structured Clinical Interview for DSM-IV Diagnoses. Across-task WIV for performance speed and accuracy on the PennCNB was calculated. Multivariate linear regression was used to assess the relationship between WIV and a diagnosis of schizophrenia in the whole sample, and WIV and selected demographic and clinical variables in people with schizophrenia.

RESULTS

Increased WIV of performance speed across cognitive tests was significantly associated with a diagnosis of schizophrenia. In people with schizophrenia, increased speed WIV was associated with older age, a lower level of education and a lower score on the Global Assessment of Functioning scale. Increased accuracy WIV was significantly associated with a younger age in people with schizophrenia.

CONCLUSIONS

Measurements of WIV of performance speed can add to the knowledge gained from studies of cognitive dysfunction in schizophrenia in resource-limited settings.

Patterns of Impaired Neurocognitive Performance on the Global Neuropsychological Assessment, and Their Brain Structural Correlates in Recent-onset and Chronic Schizophrenia

Objective

Schizophrenia is associated with impairment in multiple cognitive domains. There is a paucity of research on the effect of prolonged illness duration (≥ 15 years) on cognitive performance along multiple domains. In this pilot study, we used the Global Neuropsychological Assessment (GNA), a brief cognitive battery, to explore the patterns of cognitive impairment in recent-onset (≤ 2 years) compared to chronic schizophrenia (≥ 15 years), and correlate cognitive performance with brain morphometry in patients and healthy adults.

Methods

We assessed cognitive performance in patients with recent-onset (n = 17, illness duration ≤ 2 years) and chronic schizophrenia (n = 14, duration ≥ 15 years), and healthy adults (n = 16) using the GNA and examined correlations between cognitive scores and gray matter volumes computed from T1-weighted magnetic resonance imaging images.

Results

We observed cognitive deficits affecting multiple domains in the schizophrenia samples. Selectively greater impairment of perceptual comparison speed was found in adults with chronic schizophrenia (p = 0.009, η2partial = 0.25). In the full sample (n = 47), perceptual comparison speed correlated significantly with gray matter volumes in the anterior and medial temporal lobes (TFCE, FWE p < 0.01).

Conclusion

Along with generalized deficit across multiple cognitive domains, selectively greater impairment of perceptual comparison speed appears to characterize chronic schizophrenia. This pattern might indicate an accelerated or premature cognitive aging. Anterior-medial temporal gray matter volumes especially of the left hemisphere might underlie the impairment noted in this domain in schizophrenia.

Assessing the impact of sleep restriction on the attention and executive functions of medical students: a prospective cohort study

OBJECTIVE

To compare the performance of medical students regarding attention and executive functions during a period of sleep restriction (insufficient sleep; period of classes) and a period of free sleep (sufficient sleep; vacation period).

BACKGROUND

Sleep deprivation is associated with poor academic outcomes. Few studies have assessed the cognitive changes associated with sleep deprivation due to insufficient sleep syndrome in students and how they occur in real-life situations.

METHODS

This was a prospective cohort study. Medical students were assessed at two moments (class and vacation). The interval between assessments was 30 days. The Pittsburgh Sleep Quality Index, the Consensus Sleep Diary, the Montreal Cognitive Assessment, the Psychomotor Vigilance Test (PVT) and the Wisconsin Sorting Cards Test were used.

RESULTS

Forty-one students were assessed, 49% were female, with a median age of 21 (20; 23) years. There was a lower number of hours slept (5.75 (5.4; 7.0) vs 7.33 (6.0; 8.0) hours; p = 0.037), and a significantly poorer performance in the PVT (mean reaction time, p = 0.005; Minor lapses, p = 0.009) during the period of classes when compared to the vacation period. There was a correlation between the variation in hours of sleep of the two assessments and a variation in minor lapses in the two assessments (Ro: -0.395; p = 0.011; Spearman's correlation).

CONCLUSIONS

Students had fewer hours of sleep and more reduced attention during the period of classes than during the vacation period. This decrease in sleeping hours was correlated with more impaired attention.

Association between ambulatory blood pressure monitoring patterns with cognitive function and risk of dementia: a systematic review and meta-analysis

BACKGROUND

The objective of this systematic review and meta-analysis is to investigate whether nocturnal blood pressure fall, expressed by dipping patterns according to 24 h ambulatory blood pressure monitoring (ABPM), is associated with abnormal cognitive function (cognitive impairment or dementia).

METHODS

We systematically searched PubMed, Embase, and Cochrane databases to identify original articles through December 2022. We included any study with at least ten participants reporting on all-cause dementia or cognitive impairment incidence (primary outcome) or validated cognitive tests (secondary outcome) among ABPM patterns. We assessed risk of bias using Newcastle-Ottawa Quality Assessment Scale. We pooled odds ratios (OR) and standardized mean differences (SMD) using random-effect models for primary and secondary outcome, respectively.

RESULTS

In the qualitative synthesis, 28 studies examining 7595 patients were included. The pooled analysis of 18 studies showed that dippers had a 51% [OR 0.49(0.35-0.69)] lower risk of abnormal cognitive function and a 63% [OR 0.37(0.23-0.61)] lower risk of dementia alone, compared to non-dippers. Reverse dippers presented an up to sixfold higher risk [OR 6.06(3.15-11.64)] of abnormal cognitive function compared to dippers and an almost twofold higher risk [OR 1.81(1.26-2.6)] compared to non-dippers. Reverse dippers performed worse in global function neuropsychological tests compared with both dippers [SMD - 0.66(- 0.93 to - 0.39)] and non-dippers [SMD - 0.35(- 0.53 to - 0.16)].

CONCLUSION

Dysregulation of the normal circadian BP rhythm, specifically non-dipping and reverse dipping is associated with abnormal cognitive function. Further studies are required to determine potential underlying mechanisms and possible prognostic or therapeutic implications.

PROTOCOL REGISTRATION

PROSPERO database (ID: CRD42022310384).

A Network Analysis of Executive Functions in Children and Adolescents With and Without Attention-Deficit/Hyperactivity Disorder

This study applied network analysis to executive function test performances to examine differences in network parameters between demographically matched children and adolescents with and without attention-deficit/hyperactivity disorder (ADHD) (n = 141 per group; M = 12.7 ± 2.9 years-old; 72.3% boys, 66.7% White, 65.2% ≥ 12 years maternal education). All participants completed the NIH Toolbox Cognition Battery, including the Flanker, measuring inhibition, Dimensional Change Card Sort, measuring shifting, and List Sorting test, measuring working memory. Children with and without ADHD had comparable mean test performances (d range: .05-0.11) but presented with differences in network parameters. Among participants with ADHD, shifting was less central, had a weaker relationship with inhibition, and did not mediate the relationship between inhibition and working memory. These network characteristics were consistent with the executive function network structure of younger ages in prior research and may reflect an immature executive function network among children and adolescents with ADHD, aligning with the delayed maturation hypothesis.

Associations Between Objectively Measured Sleep and Cognition: Main Effects and Interactions With Race in Adults Aged ≥50 Years

BACKGROUND

This study examined associations of actigraphy-estimated sleep parameters with concurrent and future cognitive performance in adults aged ≥ 50 years and explored interactions with race.

METHODS

Participants were 435 cognitively normal adults in the Baltimore Longitudinal Study of Aging who completed wrist actigraphy at baseline (mean = 6.6 nights) and underwent longitudinal testing of memory, attention, executive function, language, and visuospatial ability. On average, participants with follow-up data were followed for 3.1 years. Primary predictors were baseline mean total sleep time, sleep onset latency, sleep efficiency (SE), and wake after sleep onset (WASO). Fully adjusted linear mixed-effects models included demographics, baseline health-related characteristics, smoking status, sleep medication use, APOE e4 carrier status, and interactions of each covariate with time.

RESULTS

In adjusted models, higher SE (per 10%; B = 0.11, p = .012) and lower WASO (per 30 minutes; B = -0.12, p = .007) were associated with better memory cross-sectionally. In contrast, higher SE was associated with greater visuospatial ability decline longitudinally (B = -0.02, p = .004). Greater WASO was associated with poorer visuospatial ability cross-sectionally (B = -0.09, p = .019) but slower declines in visuospatial abilities longitudinally (B = 0.02, p = .002). Several sleep-cognition cross-sectional and longitudinal associations were stronger in, or limited to, Black participants (compared to White participants).

CONCLUSIONS

This study suggests cross-sectional sleep-cognition associations differ across distinct objective sleep parameters and cognitive domains. This study also provides preliminary evidence for racial differences across some sleep-cognition relationships. Unexpected directions of associations between baseline sleep and cognitive performance over time may be attributable to the significant proportion of participants without follow-up data and require further investigation.

Volumetric regional MRI and neuropsychological predictors of motor task variability in cognitively unimpaired, Mild Cognitive Impairment, and probable Alzheimer's disease older adults

INTRODUCTION

The mechanisms linking motor function to Alzheimer's disease (AD) progression have not been well studied, despite evidence of AD pathology within motor brain regions. Thus, there is a need for new motor measure that is sensitive and specific to AD.

METHODS

In a sample of 121 older adults (54 cognitive unimpaired [CU], 35 amnestic Mild Cognitive Impairment [aMCI], and 32 probable mild AD), intrasubject standard deviation (ISD) across six trials of a novel upper-extremity motor task was predicted with volumetric regional gray matter and neuropsychological scores using classification and regression tree (CART) analyses.

RESULTS

Both gray matter and neuropsychological CART models indicated that motor task ISD (our measure of motor learning) was related to cortical regions and cognitive test scores associated with memory, executive function, and visuospatial skills. CART models also accurately distinguished motor task ISD of MCI and probable mild AD from CU.

DISCUSSION

Variability in motor task performance across practice trials may be valuable for understanding preclinical and early-stage AD.

Harmonizing Ethno-Regionally Diverse Datasets to Advance the Global Epidemiology of Dementia

Understanding dementia and cognitive impairment is a global effort needing data from multiple sources across diverse ethno-regional groups. Methodological heterogeneity means that these data often require harmonization to make them comparable before analysis. We discuss the benefits and challenges of harmonization, both retrospective and prospective, broadly and with a focus on data types that require particular sorts of approaches, including neuropsychological test scores and neuroimaging data. Throughout our discussion, we illustrate general principles and give examples of specific approaches in the context of contemporary research in dementia and cognitive impairment from around the world.

Cognitive impairment in multiple sclerosis: Utility of electroencephalography

OBJECTIVE

to evaluate associations between neurocognitive impairment and electroencephalography (EEG) data in Multiple Sclerosis (MS).

METHODS

patients aged between 18 and 65 years, diagnosed with MS accordingly to the McDonald 2017 criteria and who were in remission for at least one month were included. Cognitive functions were evaluated by validated neuropsychological tests for Tunisian population. Electroencephalography data of each patient were analysed, Grand Total EEG (GTE) score was calculated and we evaluated their statistical links with cognitive impairment.

RESULTS

Thirty five patients were included. Slower background activity was associated with presence of: reduced information processing speed (IPS) (p = 0,03), verbal memory impairment (p = 0,04) and executive dysfunction (p = 0,016). The score 3 of GTE (reactivity of background activity) was associated with reduced IPS (p = 0,007) and executive dysfunction (p = 0,014). We found a positive correlation between background activity and Tunisian Verbal Test (TVLT) (ρ =0,46 ; p = 0,005) and Symbol Digit Modalities Test (SDMT) (ρ =0,35 ; p = 0,03). Sensitivity of GTE score was 68,4% for executive dysfunction (cut-off=2,5) and 66,7% for reduced IPS (cut-off=2,5).

CONCLUSIONS

Our results have shown utility of EEG in detecting cortical involvement and its correlation with cognitive impairment in MS patients.

SIGNIFICANCE

EEG could be a tool for monitoring cortical involvement during MS and predict cognitive impairment.

The Accuracy of Speech and Linguistic Analysis in Early Diagnostics of Neurocognitive Disorders in a Memory Clinic Setting

OBJECTIVE

To investigate whether automatic analysis of the Semantic Verbal Fluency test (SVF) is reliable and can extract additional information that is of value for identifying neurocognitive disorders. In addition, the associations between the automatically derived speech and linguistic features and other cognitive domains were explored.

METHOD

We included 135 participants from the memory clinic of the Maastricht University Medical Center+ (with Subjective Cognitive Decline [SCD; N = 69] and Mild Cognitive Impairment [MCI]/dementia [N = 66]). The SVF task (one minute, category animals) was recorded and processed via a mobile application, and speech and linguistic features were automatically extracted. The diagnostic performance of the automatically derived features was investigated by training machine learning classifiers to differentiate SCD and MCI/dementia participants.

RESULTS

The intraclass correlation for interrater reliability between the clinical total score (golden standard) and automatically derived total word count was 0.84. The full model including the total word count and the automatically derived speech and linguistic features had an Area Under the Curve (AUC) of 0.85 for differentiating between people with SCD and MCI/dementia. The model with total word count only and the model with total word count corrected for age showed an AUC of 0.75 and 0.81, respectively. Semantic switching correlated moderately with memory as well as executive functioning.

CONCLUSION

The one-minute SVF task with automatically derived speech and linguistic features was as reliable as the manual scoring and differentiated well between SCD and MCI/dementia. This can be considered as a valuable addition in the screening of neurocognitive disorders and in clinical practice.

Convenient Auditory-Based Language and Executive Function Test for Patients With Amyotrophic Lateral Sclerosis: A Pilot Study

OBJECTIVE

About 30%-50% of patients with amyotrophic lateral sclerosis (ALS) show cognitive impairment ranging from mild dysexecutive syndrome to frontotemporal dementia. We aimed to develop a brief cognitive test, convenient auditory-based language and executive function test (CABLET), for rapid detection of cognitive impairment in ALS, with reduced load on motor function.

METHOD

The CABLET comprises two tests using auditory verbal stimuli: Test 1, assessing word repetition and lexical judgment, and Test 2, evaluating verbal short-term memory and semantics knowledge. The administration time of Test 1 and Test 2 was 1 and 3-5 min, respectively. Overall, 61 patients with ALS and 46 age-, sex-, and education-matched healthy controls participated in this study. All participants underwent existing neuropsychological tests and the CABLET. We investigated the applicability of the CABLET to detect ALS with cognitive impairment (ALSci) from normal cognition.

RESULTS

Receiver operating characteristic analyses showed that both the CABLET total and Test 2 had good diagnostic accuracy (area under the curve [AUC]: total = 0.894, Test 2 = 0.893). Test 2 had the highest sensitivity (100% sensitivity and 71.4% specificity). No significant difference existed in the AUC between the analyses with and without age, education, and disease severity as covariates. Correlations were observed between the CABLET and established neuropsychological tests, supporting its good convergent validity.

CONCLUSIONS

Our findings indicated that the CABLET could be useful in identifying ALSci quickly without adjusting for confounding factors. Further validation is required to evaluate it in larger groups and compare with ALS-specific cognitive screen.

Long-term neurocognitive functioning of children treated with propranolol or atenolol for infantile hemangioma

The purpose of this study was to compare long-term neurocognitive functioning (working memory, processing speed, and attention) between children who had been treated with either propranolol or atenolol for infantile hemangioma during infancy. All eligible children (n = 158) aged 6 years or older and treated with propranolol or atenolol as infants were invited to participate in this two-center cross-sectional study. The primary outcome was the Wechsler Intelligence Scale for Children-V Cognitive Proficiency Index (CPI), a measure of working memory, processing speed, and attention. Secondary outcomes were general intelligence, auditory, visuospatial, and narrative memory, as well as executive functioning and sleep. A total of 105 children, of whom 36 had been treated with propranolol (age 6.0-11.8 years, follow-up time 1.6-9.7 years, 19% male) and 69 had been treated with atenolol (age 6.9-9.7 years, follow-up time 4.5-8.4 years, 19% male), were analyzed. The CPI and other neurocognitive outcomes did not differ between the propranolol and atenolol groups and were in line with general population test norms. Post hoc analyses revealed lower CPI scores for males, both compared to participating females (10.3 IQ points, medium effect size) and compared to matched test norms (12.4 IQ points, medium effect size).

CONCLUSIONS

 Long-term neurocognitive functioning did not differ between children treated with propranolol and those treated with atenolol for IH. Overall, propranolol and atenolol appear to be safe treatments for IH regarding long-term neurocognitive functioning. The substantially lower CPI scores in males warrant further investigation.

TRIAL REGISTRATION

 Netherlands Trial Register, NL7703 https://www.trialregister.nl/trial/7703 What is Known: • Infants with infantile hemangioma are effectively treated with propranolol or atenolol. • Parents and professionals are concerned about long-term neurocognitive effects.

WHAT IS NEW

• No long-term (≥ 6 years) differences in neurocognitive functioning were found between children treated with propranolol or atenolol. • Males treated with beta-blockers had substantially lower IQ scores than treated females and males from the general population, which is a matter of concern and should be considered when evaluating the risk/benefit ratio in less severe forms of infantile hemangioma.

Visuospatial processing skills following unilateral arterial ischemic stroke in childhood

Due to the rare occurrence of childhood stroke, its impact on later cognitive functioning remains unclear. While it is often assumed that children recover better than adults, recent studies suggest that childhood stroke can negatively affect a wide range of cognitive domains, such as attention, language, and processing speed, among others. We examined the effect of unilateral stroke on children's visuoconstructive ability and visual memory. Seventeen children with left- or right-sided arterial ischemic stroke were tested using subtests of the Hamburg-Wechsler Intelligenztest für Kinder and the Rey-Osterrieth Complex Figure (ROCF). The ROCF was evaluated both quantitatively and qualitatively with the help of two separate scoring methods. We found that lesion laterality and age at stroke impacted childhood stroke patients' ability to recall certain elements of the figure. Regarding lesion laterality, left-sided stroke patients had more difficulties recalling internal details than right-sided stroke patients. In terms of age, patients with stroke onset before the age of 5 years remembered fewer structural elements than patients with stroke onset after the age of 5 years did. Moreover, the qualitative scoring method better differentiated between individuals and between groups than the more commonly used quantitative method. The results of this study not only highlight the importance of a qualitative assessment of the ROCF but could also aid clinicians in testing stroke patients more accurately and tailoring subsequent therapy to the patient's individual needs.

Open assessment of the therapeutic and rate-dependent effects of brain balance center® and interactive metronome® exercises on children with attention deficit hyperactivity disorder

The aim of this open study was to delineate domains of benefit and effect size measures to design an appropriately powered randomized control trial to assess the efficacy of Brain Balance^@ exercises and Interactive Metronome^@ training (BB/IM) on ADHD symptoms in children. Participants underwent an extensive 15-week, 5 time per week, at-home training program. Results were assessed in 16 youths with ADHD (14M/2F, 10.8±1.7 years) who completed the program and compared to 8 typically developing controls (4M/F4, 11.0±1.8 years). BB/IM was associated with a significant reduction of 8.3 and 8.2 points on the Conner's Parent Rating Scale - Revised and the ADHD Rating Scale - IV. BB/IM was not associated with improvement on the Quotient ADHD System but with rate-dependent effects on hyperactivity and attention that were similar to previously reported effects of low dose methylphenidate. Both therapeutic and rate-dependent effects were observed on the Tower of London. The study provides information that could be used to design a randomized control trial, which is required for proof of efficacy. A key limitation is that 59% of the 39 enrolled participants with ADHD dropped out of the study and a new study should include multiple ratings during the course of treatment.