Modal Testing Research Articles

BIOLOGICAL AGE AND COGNITIVE PERFORMANCE AMONG LATE MID-LIFE WOMEN

Abstract Older biologic age, indicated by accelerated epigenetic aging, may place women at risk for poorer cognitive performance as they age. However, findings are inconsistent and based upon limited neuropsychological batteries. Studies of midlife women are few, yet women comprise two thirds of those with Alzheimer’s disease, and midlife is a critical transition and potential window for early intervention. We tested whether greater epigenetic age would be associated with poorer cognitive performance among late midlife women. 224 MsBrain study participants (average age=59 years, 82% White, 14% Black, 4% other ethnicities) underwent phlebotomy, including epigenetic aging clock estimates (GrimAge, DunedinPACE, PCPhenoAGE), and a neuropsychological battery assessing global cognitive function (Montreal Cognitive Assessment), verbal learning and memory (California Verbal Learning Test), working memory and attention (Letter Number Sequencing), letter fluency (P, R, W); semantic fluency (animal task), spatial ability (Card Rotations), processing speed (Symbol Digit Modalities Test), and perceptual speed (Finding A’s). In linear regression models controlling for age, race, and education, older PCPhenoAge was associated with poorer global cognitive performance [B(SE)=-.07(.03), p=.01], verbal memory [B(SE)=-.09(.03), p=.006], working memory [B(SE)=-.12(.03), p=.0001], attention [B(SE)=-.10(.04), p=.02], spatial ability [B(SE)=-.77(.34), p=.02], processing speed [B(SE)=-.24(.09), p=.007], and somewhat lower letter fluency [B(SE)=-.23(.13), p=.07]. GrimAge and DunedinPACE showed similar yet less consistent patterns. Interactions by race (p’s<.05) indicate that associations between older biologic age and poorer cognitive performance (verbal learning, verbal memory, processing speed) was particularly pronounced among Black women in the sample. Older biologic age is associated with poorer cognitive performance across multiple domains among late midlife women, particularly for Black women. Biologic age may serve as an early indicator of risk that could help identify women warranting early intervention to help maintain cognitive function. Supported by NIH RF1AG053504, R01AG053504, K24HL123565

Blood-based biomarkers for Alzheimer's disease and cognitive function from mid- to late life.

We investigated associations of Alzheimer's disease (AD) serum biomarkers with longitudinal changes in cognitive function from mid- to late life among women. The study population included 192 women with the median age of 53.3 years at baseline, from the Study of Women's Health Across the Nation Michigan Cohort, followed up over 14 years. Associations between baseline serum amyloid β (Aβ)42, the Aβ42/40 ratio, phosphorylated tau181 (p-tau181), and total tau with longitudinal changes in cognition were evaluated using linear mixed effects models. After adjusting for confounders, lower Aβ42/40 ratios were associated with faster declines in the Digit Span Backward Test. Higher p-tau181 also showed a borderline statistically significant association with more rapid decline in the Symbol Digit Modalities Test. Our findings suggest that mid-life serum AD biomarkers could be associated with accelerated cognitive decline from mid- to late life in women. Future studies with larger samples are needed to validate and extend our findings. This study investigates midlife serum AD biomarkers on longitudinal cognitive function changes in women. Mid-life serum AD biomarkers are associated with accelerated cognitive decline. A decrease in the Aβ42/40 ratio was associated with a faster decline in the DSB score. A higher p-tau181 concentration was associated with a faster decline in the SDMT score.

ASSOCIATION OF RAPID EYE MOVEMENT SLEEP AND APOE PROTEOTYPE TO COGNITIVE PERFORMANCE IN OLDER ADULTS

Abstract Exploring the multifaceted interaction of sleep, disease-related biomarkers and cognitive decline is of particular importance for aging populations. Sleep quality and the APOE E3/E4 allele has been linked to Alzheimer’s Disease (AD). This study aims to examine relationships between older adults’ level of cognitive performance, proportion of rapid eye movement (REM) sleep, and APOE proteotype. Analysis of sleep study data collected in an active lifestyle retirement community - The Villages, Florida was conducted using a subset of markers collected as part of a larger cognitive health study. Polysomnography, cognitive battery (Montreal Cognitive Assessment(MoCA), Trail Making Tests(TMT), Symbol Digit Modalities Test(SDMT), Psychomotor Vigilance Test(PVT)), and APOE blood-biomarker (E2/E3,E3/E3,E3/E4) data were obtained from healthy participants (n=33) aged 55-65. Descriptive statistics, multilinear regression, and ANOVA were used. Participants’ mean age was 61.9 years, with 55% being male. Cognitive test scores did not show a significant relationship with REM sleep percentage (p=0.3096). No consistent dispersion or skew was shown in box plot analysis of APOE proteotype across cognitive performance measures. Unexpectedly, although not statistically significant (p=0.396), average REM sleep percentage was higher in the APOE E3/E4 group (20.04%, Mean:75.44 minutes) as compared to the E3/E3 group (15.99%,Mean: 59.07 minutes). Proteotype E3/E4 was examined specifically due to its potential association with Alzheimer’s disease. The REM sleep proportion was lower than the average experienced on a typical night at home, possibly due to study conditions. Further research is needed examining the relationship between older adults with REM sleep insufficiency and cognitive impairment.

Deep learning-based vibration stress and fatigue-life prediction of a battery-pack system

The primary concerns of the automotive industry are structural integrity and battery-pack system (BPS) reliability. To ascertain the appropriate thickness of critical BPS components (e.g., the long bracket, crossbeam, and bottom shell), engineers are required to perform several simulations of finite element (FE) analysis. This procedure is laborious and requires a significant amount of time. This study introduces a very effective approach for predicting vibration-induced stress and fatigue life, intending to enhance dependability in the design process. Firstly, a three-layer lithium battery model is utilized to investigate the impact of vibration on the maximal Mises stress at various states of charge. This information is used to model the BPS, including the batteries. The nonlinear FE model of the BPS is validated using the modal test results. Secondly, a sensitivity analysis is performed to ascertain the impact of component thickness on the maximum Mises stress. For vibration simulations, multiple design variables are selected to collect data. Next, the nonlinear relationship between inputs (thicknesses of critical components) and outputs (maximum Mises stress and minimum fatigue life) is described using a deep learning (DL) modeling framework with forward and backward propagation. Finally, the accuracy of the DL model is assessed by measuring error functions and comparing its performance to six commonly employed methods. Furthermore, the inclusion of Gaussian noise is employed to assess the model’s robustness and ability to generalize. Additionally, the establishment of fatigue-life and stress boundaries serves to offer designers valuable insights. The results indicate that the proposed method for predicting vibration stress and fatigue life is highly efficient and cost-effective, making it useful for the design of a robust and reliable BPS.

Dynamic modeling and analysis of the rotor–stator coupling system of a coaxial contra-rotating gearbox

In this paper, a main gearbox using an encased differential gear train to achieve coaxial contra-rotating is considered, and a dynamic modeling method of the rotor–stator coupling system of the gearbox based on box model updating is introduced. The transverse torsional dynamic model of the gear transmission subsystem is established based on the lumped parameter method. The finite element model of the box is updated according to the modal test data, and the reduced dynamic parameters of the box are obtained. According to the displacement coordination condition, the dynamic model of the rotor–stator system of the gearbox is established. The vibration response of the transmission components with or without the coupling box is calculated by numerical integration, and the response of the box caused by the dynamic support reaction force is analyzed by the finite element method. The results show that the vibration peak and fluctuation range of the transmission parts with coupling box are smaller than those without coupling box. The box response at the support of the input bevel gear pair is large, while that at the support of the output shaft is small.

Improving the ecological validity of isokinetic knee tests at different hip angles: reciprocal concentric-eccentric movements as a suitable alternative for discrete tests

ABSTRACT Isokinetic knee tests mostly evaluate reciprocal concentric-concentric flexor-extensor movements in a seated position. Discrete tests generate higher moments, but time requirements impede their widespread implementation. This study examined if hip angle (flexed vs. extended) and test modality (discrete vs. reciprocal) affect camera-based data (100 fps). Sixteen healthy males performed concentric (con) and eccentric (ecc) isokinetic knee flexor (H) and extensor (Q) movements (60°/s). Peak moments and contractional work of discrete and reciprocal tests (QconQecc, HconHecc) strongly correlated for extended (Q:91%≥R2≥71%; H:95%≥R2≥87%) and flexed hip (Q:88%≥R2≥70%; H:81%≥R2≥75%) without significant differences (p>0.05) between test modalities. Discrete and “traditional” seated QconHcon-tests revealed substantially lower correlations for extended (Q:44%≥R2≥43%; H:55%≥R2≥54%) and flexed hip (Q:81%≥R2≥77%; H:48%≥R2≥47%). Although most mean values did not significantly differ, moderate correlations were predominant and the respective limits of agreement demonstrated considerable effects of hip angle and test modality. These insights assist practitioners in interpreting isokinetic data of different test procedures. If time constraints prevent discrete knee tests (gold standard), concentric-eccentric movements provide highly correlated outcomes, independent of the hip angle.

Damping, wave attenuation and damage of local-resonance-based metaconcrete slabs: Experimental investigation

Metaconcrete has the potential ability of wave attenuation and vibration reduction, but there is still a lack of engineering component preparation and dynamic performance testing. In this research, metaconcrete slabs were designed and prepared, and modal tests and explosion tests were carried out. The high modal damping performance and vibration reduction characteristics of metaconcrete slabs were verified through modal tests. The wave attenuation performance, dynamic damping effect, anti-cracking and anti-spalling performance of metaconcrete slabs were verified through explosion tests. It is found that after adding resonators, the damping coefficient of the concrete slab significantly increases, and the crack width and spalling range decrease under blast load. These results show that metaconcrete slabs exhibit good dynamic performance and have the potential to be used in protective engineering.

Multi-modal neuroimaging signatures predict cognitive decline in multiple sclerosis: A 5-year longitudinal study

BackgroundCognitive impairment is a hallmark of multiple sclerosis (MS) but is usually an under-recorded symptom of disease progression. Identifying the predictive signatures of cognitive decline in people with MS (pwMS) over time is important to ensure effective preventative treatment strategies. Structural and functional brain characteristics as measured by various magnetic resonance (MR) methods have been correlated with variation in cognitive function in MS, but typically these studies are limited to a single MR modality and/or are cross-sectional designs. Here we assess the predictive value of multiple different MR modalities in relation to cognitive decline in pwMS over 5 years. MethodsA cohort of 43 pwMS was assessed at baseline and 5 years follow-up. Baseline (input) data consisted of 70 multi-modal MRI measures for different brain regions including magnetic resonance spectroscopy (MRS), diffusion tensor imaging (DTI) and standard volumetrics. Age, sex, disease duration and treatment were included as clinical inputs. Cognitive function was assessed using the Audio Recorded Cognitive Screen (ARCS) and the Symbol Digit Modalities Test (SDMT). Prediction modelling was performed using the machine learning package - GLMnet, where a penalised regression was applied to identify multi-modal signatures with the most predictive value (and the least error) for each outcome. ResultsThe multi-modal approach to neuroimaging was able to accurately predict cognitive decline in pwMS. The best performing model for change in total ARCS (tARCS) included 16 features from across the various MR modalities and explained 54 % of the variation in change over time (R2=0.54, 95 % CI=0.48–0.51). The features included nine MRS, four volumetric and two DTI parameters. The model also selected disease duration, but not treatment, as a predictive feature. By comparison, the best model for SDMT included several of the same above features and explained 39 % of the change over time (R2=0.39, 95 % CI=0.48–0.51). Conventional volumetric measures were about half as good at predicting change in tARCS score compared to the best multi-modal model (R2=0.26 95 % CI:0.22–0.29). The clinical interpretation of the best predictive model for change in tARCS showed that cognitive decline could be predicted with >90 % accuracy in this cohort (AUC=0.92, SE=0.86 - 0.94). ConclusionMulti-modal MRI signatures can predict cognitive decline in a cohort of pwMS over 5 years with high accuracy. Future studies will benefit from the inclusion of even more MR modalities e.g., functional MRI, quantitative susceptibility mapping, magnetisation transfer imaging, as well as other potential predictors e.g., genetic and environmental factors. With further validation, this signature could be used in future trials with high-risk patients to personalise the management of cognitive decline in pwMS, even in the absence of relapses.

Strategies for Reducing Booming Noise Generated by the Tailgate of an Electric Sport Utility Vehicle

This article investigates the source of booming noise emanating from the tailgate of an electric sport utility vehicle (SUV), along with proposed strategies to mitigate it. This annoying low-frequency booming noise, which significantly impacts interior sound quality, is less perceptible in conventional internal combustion engine vehicles. However, this noise is more readily detected in electric SUVs, highlighting the necessity for focused measures to reduce it. This study involved the measurement of booming noises during on-road vehicle tests to pinpoint their origins. Additionally, ODSs were extracted from the tailgate vibration signals to gain insight into its dynamic behavior. Modal tests were conducted on the tailgate to determine its dynamic characteristics and compared with driving test results to reveal the mechanism responsible for tailgate-induced booming noise. It was established that such noise is primarily due to the tailgate modes, resulting from a combination of rigid body motion in the fore-aft direction and deformation in the central section of the panel. An analytical model of the tailgate was developed using commercial finite-element analysis software to propose measures for reducing booming noise. Experimental findings validated this model’s accuracy. Structural enhancements were implemented to enhance the panel stiffness and improve the connection between the vehicle and tailgate via bushings to reduce the booming noise resulting from tailgate motion. Under random force inputs, the analytical results demonstrated a 13.8% reduction in maximum deformation in the tailgate model in the improved structural configuration with increased panel stiffness. This study identifies the mechanism generating booming noise, establishes a practical and simple dynamic model, and proposes improvement measures aimed at reducing the booming noise.

Research on acoustic-structural coupling model and tire parameters of tire acoustic cavity resonance noise

Tire acoustic cavity resonance (TACR) noise is one kind of low-frequency and narrowband noise that particularly annoys passengers, especially becomes more prominent in electric vehicles. This paper demonstrates a numerical investigation on the TACR noise via the acoustic-structural coupling finite element model. The accuracy of this coupling finite element model is validated both by the analytic method based on the superposition theory of traveling waves and experimental modal tests of tire cavities. According to the simulated models, the influences of external factors including the inflation pressure and road load on the TACR noise are studied. Meanwhile, as the main constituent component in the tire model, the effect of belt cord is also discussed. To design the low-TACR noise tire, various design parameters of the inner contour in tire cavity are analyzed. By the orthogonal test and range analysis, it is found that the contour parameters can slightly affect the modal frequency and sound pressure of TACR noise. Among these, the curvature radius of the tire shoulder ρ 4, tire sidewall ρ 5, and half-section height H have a more obvious influence on the TACR noise than the curvature radius of the tire crown region ρ 2 and transition region ρ 3. Meanwhile, it also illustrates that increasing the curvature radius at the tire shoulder ρ 4 and reducing the half-section height H has a reduction effect on the TACR noise. This study can contribute to the design of low road noise tires.

Comparison of Subspace Identification Methods for Modal Estimation of Bladed Disks

Abstract Bladed disks are critical parts of aeronautic turbojet engines requiring numerous dynamic analysis tests to fully achieve their design process. This work presents subspace state-space identification techniques for estimation of modal parameters of bladed disks using realistic although numerically generated test case data. Indeed, modal testing of bladed disks can exhibit high modal density leading to modal estimation issues. This study focuses on subspace state-space identification framework as it is an efficient way to process vector valued time series and thus to estimate modal parameters in a context of high modal density. In order to evaluate the techniques of interest, a versatile modal model has been specifically implemented to simulate data representative of full scale rotating aeronautic fan modal tests. This model is easily adjustable allowing to evaluate the identification methods in a more or less severe estimation context. The performance of the investigated methods is discussed and compared with the prescribed parameters of the model. Moreover, different techniques to estimate the order of the associated state-space model are reviewed and tested over several simulated configurations. Finally, a method to evaluate the uncertainties over the model parameters using covariance of estimator results and pseudospectrum computation is proposed and discussed over the investigated test cases.

Bioinspired Design for Lightweighting and Vibration Behavior Optimization in Large-Scale Aeronautical Tooling: A Comparative Study

A comparative study is presented, focusing on three different bioinspired design methodologies applied to a large-scale aeronautical tooling use case. The study aims to optimize the structure in terms of the first vibration mode, minimizing mass, and supporting operational loads. The development of lightweight metallic components is of great importance for industries such as aerospace, automotive, and energy harvesting, where weight reduction can lead to significant improvements in performance, efficiency, and sustainability. Bioinspired design offers a promising approach to achieving these goals. The study begins with an introduction to natural selection and various bioinspired concepts. It proceeds with a thorough review of the selected bioinspired design methodologies and tools, which are then applied to the chosen use case. The outcomes for each methodology were explored with respect to the design requirements. Subsequently, the most suitable design was selected according to the success criteria defined and its validation is explained. The manufacturing of this design was carried out using an advanced and novel approach specifically tailored to accommodate the large dimensions and complexity of the structure. Finally, modal testing was performed to validate the entire process, and the results obtained demonstrate the potential effectiveness of bioinspired design methodologies in achieving lightweighting and optimizing vibration modes for large-scale aeronautical tooling.

Effect of delamination on the dynamic characteristics of thin‐walled carbon fiber‐reinforced polymer tube

AbstractThin‐walled carbon fiber‐reinforced‐polymer (CFRP) tubes are susceptible to damage, which impacts their dynamic characteristics. This paper investigates the influence of delamination damage on the dynamic properties of thin‐walled CFRP tubes through finite element simulation and experimental methods. A transversely isotropic principal model is employed to establish the geometric model. Delamination damage is induced using the cohesive zone model and the secondary stress criterion. Both circumferential and elliptical delamination cases are studied. The modal test is conducted using the hammer excitation method. It is observed that the finite element model aligns with the experimental results. It is discovered that the larger the delamination size, the lower the natural frequency for a given damage location. The location of the delamination within a single layer has minimal effect on the natural frequency. The natural frequency exhibits a symmetrical pattern of decreasing and then increasing as the delamination shifts from the sides toward the center layer. Positional information is discernible in the modal shape, which can be utilized for delamination detection and localization.Highlights The damage model is built by transversal isotropic equation and cohesive unit. Finite element model is built with various delamination sizes and locations for two cases. Modal tests are performed on CFRP tubes and obtained good accuracy. Effect of delamination size and location on dynamic parameters is discussed.

Research on Modal Test Method for Civil Aircraft Structure

In the process of civil aircraft development, it is of great significance to carry out a modal analysis of aircraft component structures and obtain modal parameters to verify whether the dynamic characteristics of aircraft structures meet the design requirements. This paper takes the structural modal of aircraft components as the research object and proposes the modal test method of aircraft structure, which provides effective modal test data support for the design and optimization of aircraft component structure.

Blood‐based biomarkers of Alzheimer disease as measured by a mass spectrometry assay are as accurate as CSF tests

AbstractBackgroundEspecially because disease‐modifying treatments (DMTs) for Alzheimer disease (AD) are likely to become more available soon, highly accurate AD blood tests for use in clinical diagnosis are critically needed. Although amyloid PET scans and cerebrospinal fluid (CSF) tests are highly accurate in the identification of individuals with brain amyloidosis, blood tests are likely the only test modality that will enable an adequate scale of AD biomarker testing. Mass spectrometry‐based AD blood tests have consistently demonstrated very high performance.MethodsResearch participants enrolled in studies at the Knight Alzheimer Disease Research Center who underwent amyloid PET and measurement of established CSF biomarkers of AD with Lumipulse automated assays were included. The presence and severity of dementia was evaluated with the Clinical Dementia Rating® (CDR®) and Clinical Dementia Rating Sum of Boxes (CDR‐SB). Plasma samples collected at the same session as CSF underwent analysis for specific phosphorylated and non‐phosphorylated tau species with an immunoprecipitation‐mass spectrometry assay. Plasma T217 occupancy was calculated as the percent of phosphorylated to non‐phosphorylated tau at threonine 217.ResultsThe study cohort included 337 individuals with an average age of 69.8 ± 8.3 years (mean ± standard deviation); 175 (52%) were female, 128 (38%) were APOE ε4 carriers, 112 (33%) were amyloid PET positive, and 50 (15%) were cognitively impaired. Classification accuracy of amyloid PET status was equivalent for plasma T217 occupancy (AUC 0.973) and CSF Aβ42/Aβ40 (AUC 0.970), (p = 0.72 for the difference). Interestingly, plasma T217 occupancy more accurately classified individuals as cognitively impaired (CDR>0) or cognitively unimpaired (CDR 0), with an AUC of 0.876 versus 0.814 for CSF Aβ42/Aβ40 (p = 0.006 for the difference). Further, plasma T217 occupancy was better correlated with dementia severity as measured by the CDR‐SB (Spearman ρ = 0.455 versus ‐0.338 for CSF Aβ42/Aβ40, p = 0.02).ConclusionPlasma T217 occupancy as measured by mass spectrometry had equivalent classification accuracy of amyloid PET status compared to Lumipulse CSF Aβ42/Aβ40. Notably, plasma T217 occupancy was more strongly associated with cognitive impairment and dementia severity than CSF Aβ42/Aβ40. Overall, these data suggest that some AD blood tests have equivalent or better performance characteristics than clinically used CSF tests.

Online Monitoring Dynamic Characteristics in Thin-Walled Structure Milling: A Physics-Constrained Bayesian Updating Approach

Accurate estimation of modal parameters of thin-walled structures during the milling process is crucial since it determines the accuracy of deformation and vibration prediction and then the feasibility of selected machining parameters. However, time-varying dynamic characteristic due to material removal brings a great challenge in the pursuit. This article presents an online monitoring strategy for the estimation of modal parameters of thin-walled structures with measured cutting forces and single acceleration signal. The detailed physical constraints are presented, and the analytical form of the modal shape of thin-wall structures is derived. A Bayesian filter framework with slack variables is established for updating the modal parameters by simultaneously considering the physical constraints and the measured signals. Validation experiments are conducted on two kinds of thin-walled structures with different structures. The results of the proposed method are compared with the results of the standard modal test at certain stages. It indicates that the proposed approach is effective for accurately online monitoring of the spatiotemporally varying modal parameters in milling of thin-walled structures.

Glymphatic function maintains sleep‐sensitive cognitive performance and predicts overnight changes in plasma amyloid β in humans

AbstractBackgroundDuring sleep, the glymphatic system facilitates rapid exchange of fluid through brain tissues, clearing solutes, including amyloid β (Aβ), tau, and α synuclein that accumulate through the course of waking activity. Glymphatic clearance is widely believed to underlie the restorative effects of sleep on cognition, and its impairment is proposed to reflect the biological basis for the corrosive effects of sleep disruption. We sought to determine if glymphatic function or sleep EEG predicted changes in cognitive performance and overnight differences in Aβ biomarker levels using a new non‐invasive investigational medical device (IMD) to measure glymphatic function by dynamic impedance spectro‐tomography.MethodEighteen healthy 50‐65 y/o participants were enrolled in a cross‐over randomized control clinical trial encompassing one night of sleep and one night of sleep deprivation. Participants were instrumented with the IMD and overnight change in brain parenchymal resistance to flow, R, was measured. Sleep EEG powerbands, slow (0.4‐1Hz), delta (1‐4Hz), beta (15‐30Hz), and time spent in N2, N3 and REM sleep were derived from the device EEG. In both sleep and sleep deprivation interventions, cognitive tests (symbol digit modality test, SDMT; psychomotor vigilance test, PVT) were administered at 7am and blood Aβ biomarkers (Aβ40; Aβ42) were taken at 10pm and 7am.ResultOvernight parenchymal resistance R predicted intraindividual paired differences (sleep – sleep deprivation) in cognitive test scores (A SDMT ρ = ‐0.65, p = 0.003; B PVT STD RT, ρ = 0.41, p = 0.095) and Aβ42 blood amyloid biomarker changes (C Aβ42 ρ = ‐0.53, p = 0.03; D Aβ40 ρ = ‐0.33, p = 0.21). Sleep EEG powerbands and time spent in N2, N3, and REM sleep were not predictive of sleep‐related changes in cognition or plasma Aβ biomarker levels.ConclusionGlymphatic function, measured continuously by dynamic impedance spectro‐tomography, predicted changes in the restorative effect of sleep on cognition and plasma Ab biomarker levels as hypothesized, but not previously demonstrated. In contrast, sleep EEG powerbands and time spent in N2, N3 and REM were not predictive. Detection of glymphatic impairment in real‐world settings may permit (i) early identification of individuals at‐risk for developing sleep‐related Alzheimer’s disease pathology, and (ii) enable precision targeted enhancement of glymphatic function to enhance glymphatic function and pathological protein clearance.

Effects of Cognitive‐motor Rhythmic Training on Executive Functions and Motor Performance in Older Adults with Mild Cognitive Impairment: A Randomized Controlled Trial

AbstractIntroductionIn recent years, prevalence of mild cognitive impairment (MCI) has increased in older adults, exacerbating the potential impact on global health. Cognitive‐motor training is an emerging treatment modality with proven benefits in enhancing both physical and cognitive functions. In recent research findings, training of musical rhythmic skills with auditory‐motor synchronization is beneficial to reactivate the brain’s sensorimotor and perceptual regions as well as to improve cognition. However, there is limited research on combining these modalities.ObjectivesThis pilot study aims to develop a pioneer program on cognitive‐motor rhythmic training (CMRT), and to investigate whether the program would improve the executive functions (EF) and hand functions of patients with MCI.MethodologyThirty patients recruited from the Hong Kong Buddhist Hospital were randomized into two groups: (i) an intervention group receiving a 6‐week training program and (ii) a waitlist control group. The program was designed with reference to the rhythm game “Taiko no Tatsujin”, in which precise timed motor responses were required to hit the circular cues against the target zone. The game was designed with progression of difficulty levels and instant feedback. Classical Cantopop songs that were familiar to Hong Kong older adults were selected. Mental flexibility, inhibitory control, working memory, visuospatial memory, verbal fluency, processing speed and problem‐solving were assessed using domain‐specific cognitive tests, while hand dexterity was measured by the Purdue Pegboard Test. Paired t‐test and ANOVA were used to examine the within group difference and the comparison between groups. The level of significance was set at P<0.05.ResultsThe analysis showed significant Time x Group interaction effects in Color Trail Test (p = 0.001), Color Word Stroop Test (P = 0.002), Digit Span Test (P<0.001), Corsi Block‐Tapping Test (P<0.001), Verbal Fluency Test (P<0.001), Symbol Digit Modalities Test (P = 0.015), Maze Test (P<0.001) and the Purdue Pegboard scores (P<0.001) compared to the control group after training.ConclusionsThe 6‐week CMRT program is effective in improving the executive functions and motor performance in patients with MCI. This innovation can serve as an affordable and quality intervention in early stages of cognitive decline.

The Effects of Breaking Up Prolonged Sitting on Cognitive Performance in Middle‐Aged and Older Adults: Dose Response Analysis of a Randomized Crossover Trial

AbstractBackgroundSedentary behavior (SED) is highly prevalent and associated with poor health outcomes and cognitive decline, independent of physical activity (PA). Studies have established the harmful effects on cognition and information processing, and while PA guidelines endorse reducing SED, they fail to address how often SED should be broken up, and for how long. The purpose of this study is to assess how frequently and for how long SED should be disrupted with light‐intensity physical activity (PA) to offset the effects on cognitive performance.MethodA randomized crossover study of n = 11 middle and older aged adults (>45 years) completed five 8‐hour visits: a sedentary (control) condition and four experimental conditions with varied walking (1.9 mph, 0% grade) frequency and durations: every 30 minutes for 1 minute, every 30 minutes for 5 minutes, every 60 minutes for 1 minute, and every 60 minutes for 5 minutes. Cognition was assessed at baseline, 4 hours, and 6 hours via the Single Digit Modalities Test (SDMT), a validated cognitive performance measure that assesses information processing speed and accuracy.ResultCompared with control, there was significant improvement in SDMT score for the every 30 minutes for 5 minutes dose (net difference compared to control: 3.1 [SE: 1.4], p‐value = 0.034), every 60 minutes for 1 minute dose (net difference compared to control: 3.4 [SE: 1.4], p‐value = 0.016), and every 60 minutes for 5 minutes dose (net difference compared to control: 3.3 [SE: 1.4], p‐value = 0.017). The effect on SDMT was not statistically significant for the every 30 minutes for 1 minute dose, but a positive trend was observed (net difference compared to control: 2.6 [SE: 1.4], p‐value = 0.069).ConclusionThere was a significant effect of breaking up SED on SDMT scores with light intensity walking for both low frequency breaks (1 minute every 60 minutes and for 5 minutes every 60 minutes) and high frequency breaks (5 minutes every 60 minutes). This suggests that even brief breaks in SED may offset harmful effects on cognitive performance. This result provides a specific and achievable mechanism for offsetting the harm caused by SED on cognitive performance.

Similarities and differences in cognition as a function of sex: A longitudinal study of healthy control participants from the Parkinson Progression Markers Initiative

AbstractBackgroundAs the global population of older adults continues to rise, there is an urgent need to understand the expected cognitive changes in healthy aging. Despite sex‐based differences in life expectancy and age‐related diseases such as Alzheimer’s disease, limited research has explicitly examined sex differences in aging. The objective of the current study was to answer three primary questions using longitudinal data for sample of healthy adults: 1) How does cognition change over time? 2) What are the sex differences in cognition? and 3) What are the sex differences in rates of cognitive change over time?MethodLongitudinal data from the healthy control group of the Parkinson’s Progression Markers Initiative was used to examine cognitive changes in healthy adult males (n = 125, mean age = 61.61, SD = 10.97) and females (n = 68, mean age = 59.44, SD = 11.56). Participants underwent annual neuropsychological testing for up to five years. A series of 2‐level linear mixed models estimated within‐person change in cognition over time (i.e., level‐1) and between‐group differences in longitudinal change trajectories as predicted by sex (i.e., level 2). Each neuropsychological measure was modeled separately as a single outcome variable, for a total of seven models.ResultStability in neuropsychological scores was seen over five years. At baseline, males scored higher on the Benton Judgement of Line Orientation Test, while females scored higher on the Symbol Digit Modalities Test, the Semantic Fluency Test, and the Hopkins Verbal Learning Test‐Revised. Rates of cognitive change over time did not significantly differ by sex. Higher age and lower education at baseline predicted lower neuropsychological scores.ConclusionStability in cognition was found across five years in a sample healthy control participants from a large multi‐site longitudinal study. Sex differences in cognition were found in several domains, including visuospatial ability, processing speed, verbal fluency, and verbal memory. However, rates of cognitive change over time did not significantly differ by sex. Higher age and lower education were predictive of lower cognitive functioning. Great intraindividual variability in cognitive trajectories was observed. Future research should continue to examine factors that predict individual trajectories of aging in healthy individuals.