Perturbation-based dual task assessment in older adults with mild cognitive impairment.

Background: Dual tasking (i.e., concurrent performance of motor and cognitive task) is significantly impaired in older adults with mild cognitive impairment (OAwMCI) compared to cognitively intact older adults (CIOA) and has been associated with increased fall risk. Dual task studies have primarily examined volitionally driven events, and the effects of mild cognitive impairment on reactive balance control (i.e., the ability to recover from unexpected balance threats) are unexplored. We examined the effect of cognitive tasks on reactive balance control in OAwMCI compared to CIOA. Methods: Adults >55 years were included and completed the Montreal Cognitive Assessment (MoCA) to categorize them as OAwMCI (MoCA: 18-24, n = 15) or CIOA (MoCA: ≥25, n = 15). Both OAwMCI [MoCA: 22.4 (2.2), 65.4 (6.1) years, 3 females] and CIOA [MoCA: 28.4 (1.3), 68.2 (5.5) years, 10 females] responded to large magnitude stance slip-like perturbations alone (single task) and while performing perceptual cognitive tasks targeting the visuomotor domain (target and tracking game). In these tasks, participants rotated their head horizontally to control a motion mouse and catch a falling target (target game) or track a moving object (track). Margin of stability (MOS) and fall outcome (harness load cell >30% body weight) were used to quantify reactive balance control. Cognitive performance was determined using performance error (target) and sum of errors (tracking). A 3 × 2 repeated measures ANOVA examined the effect of group and task on MOS, and generalized estimating equations (GEE) model was used to determine changes in fall outcome between groups and tasks. 2 × 2 repeated measures ANOVAs examined the effect of group and task on cognitive performance. Results: Compared to CIOA, OAwMCI exhibited significantly deteriorated MOS and greater number of falls during both single task and dual task (p < 0.05), and lower dual task tracking performance (p < 0.01). Compared to single task, both OAwMCI and CIOA exhibited significantly deteriorated perceptual cognitive performance during dual task (p < 0.05); however, no change in MOS or fall outcome between single task and dual task was observed. Conclusion: Cognitive impairment may diminish the ability to compensate and provide attentional resources demanded by sensory systems to integrate perturbation specific information, resulting in deteriorated ability to recover balance control among OAwMCI.

Evaluation of a computer game-assisted rehabilitation program for manual dexterity of children with cerebral palsy: Feasibility randomized control trial.

BACKGROUND: There is a need for innovation to improve the engagement and compliance of rehabilitation programs for children with upper extremity (UE) motor impairments due to cerebral palsy (CP); a computer games-based rehabilitation platform (GRP) was developed to address this need. The GRP provides engaging task-specific exercises targeting manual dexterity (object handling and manipulation). OBJECTIVE: To evaluate the therapeutic value and treatment effect size of an exercise program using the GRP in children with CP. METHODS: A total of 63 children with CP, aged 4 to 10 years, were recruited. The Peabody Developmental Motor Scale-2 (PDMS-2) Grasp and Visual-Motor Integration (VMI) subscores and Computer game-based Upper Extremity (CUE) assessment of manual dexterity were used to assess participants before and after a 16-week intervention program, delivered three times per week. The experimental group (XG) received a computer games-based exercise program targeting object manipulation tasks. The active control arm (CG) consisted of task-specific training similar to the tasks used in constrained induced movement therapy. RESULTS: There were only a few dropouts during the 16-week program, and compliance was high. Both groups showed significant improvements with medium to large effect sizes. Improvements in the PDMS-2 Grasp and VMI subscores observed in the XG were significantly greater than that in the CG. There were significant improvements (p < .01) in PDMS-2 grasp and VMI subscores for XG with moderate to large effect sizes (0.5-0.8). For CG, the Grasp and VMI subscores did improve but these changes were not statistically significant. There was a significant improvement observed in the majority of CUE object manipulation test scores for XG (p < .01) with moderate to large effect sizes (0.50-1.2) Although CG did show improvements in all CUE object manipulation test scores, the changes did not reach statistical significance (p < .01). CONCLUSION: This study demonstrates the utility of the GRP to practice a broad range of object manipulation tasks in children with CP. The present findings are positive and support further research and development. The long-term effects of the GRP program in children with CP will need to be confirmed in a future randomized controlled trial. In addition to measures of structure and function, future trials should also include outcome measures such as health-related quality of life and level of participation to validate the findings.

Game-Based Dual-Task Exercise Program for Children with Cerebral Palsy: Blending Balance, Visuomotor and Cognitive Training: Feasibility Randomized Control Trial.

The objective of this exploratory randomized controlled trial (RCT) was to provide evidence for the feasibility and therapeutic value of a novel game-based dual-task balance exercise program in children with cerebral palsy (CP). Twenty children with CP were recruited and randomized into two groups: (a) the conventional balance training group (CG) and (b) the experimental group (XG), which received a game-based dual-task (DT) balance exercise program. Both groups received their respective therapy programs for 12 weeks at a frequency of three sessions per week. Semi-structured interviews with the parents and children and qualitative analysis were conducted to evaluate the children's experiences with the game-based exercise program. The quantitative analysis included (a) the Pediatric Balance Scale (PBS), (b) Gross Motor Function Measure-88 (GMFM-88), and (c) computerized measures of standing balance performance during various dual-task conditions. Compliance was 100% for all 20 participants. Four themes captured the range of each participant's experiences and opinions: (a) reasons for participation, (b) likes and dislikes with the technologies, (c) positive effects of the program, and (d) future expectations. Children in the XG demonstrated greater improvements in PBS, GMFM, and DT balance measures as compared to children in the CG. The findings demonstrate feasible trial procedures and acceptable DT-oriented training with a high compliance rate and positive outcomes. These findings support further research and development and progression to the next phase of a full-scale RCT to evaluate the clinical effectiveness of the game-based DT balance exercise program for children with CP.

A computer-game-based rehabilitation platform for individuals with fine and gross motor upper extremity deficits post-stroke (CARE fOR U) - Protocol for a randomized controlled trial.

BACKGROUND & PURPOSE: Activity-based neuroplasticity and re-organization leads to motor learning via replicating real-life movements. Increased repetition of such movements has growing evidence over last few decades. In particular, computer-game-based rehabilitation is found to be effective, feasible and acceptable for post-stroke upper limb deficits. Our study aims to evaluate the feasibility and effectiveness of 12 weeks of computer-game-based rehabilitation platform (GRP) on fine and gross motor skills post-stroke in India. METHODS: Through this trial we will study the effect of adjunctive in-hospital GRP (using a motion-sensing airmouse with off-the-shelf computer games) in 80 persons with subacute stroke, for reduction of post-stroke upper limb deficits in a single-centre prospective Randomized Open, Blinded End- point trial when compared to conventional therapy alone. RESULTS: We intend to evaluate between-group differences using Wolf Motor Function test, Stroke Specific Quality of Life, and GRP assessment tool. Feasibility will be assessed via recruitment rates, adherence to intervention periods, drop-out rate and qualitative findings of patient experience with the intervention. CONCLUSION: The CARE FOR U trial is designed to test the feasibility and effectiveness of a computer-game based rehabilitation platform in treating upper limb deficits after stroke. In case of positive findings GRP can be widely applicable for stroke populations needing intensive and regular therapy with supervision.

Computer Game-Based Telerehabilitation Platform Targeting Manual Dexterity: Exercise Is Fun. "You Are Kidding-Right?"

There is a need for innovation to improve the engagement and accessibility of rehabilitation programs for children and adults with upper extremity motor impairments due to neurodevelopmental disorders, acquired brain injuries, or spinal cord injuries. For this purpose, a computer game-based telerehabilitation platform (GTP) was developed to address this need. Through the application of a miniature inertial-based computer mouse and the wide variety of commercial computer games, the developed GTP can provide engaging task-specific exercises for the rehabilitation of manual dexterity (object handling and manipulation). A purpose-built repetitive task practice software (RTP) was also developed to gather event data and synchronize it with patient movements during gameplays. This provides automated monitoring and quantification of patients' motor skills, while they practice a range of game-based exercises with their hand and/or arm. The GTP would initially be used in a supervised clinical setting followed by a transition to function at home and be monitored by clinician specialists. Clinical support for home and rural communities, with protocols that can be easily updated, will help increase accessibility to targeted and personalized solutions for patients and achieve the desired training effect.

Computerized Dual-Task Testing of Gait Visuomotor and Cognitive Functions in Parkinson's Disease: Test-Retest Reliability and Validity.

BACKGROUND: Mobility and cognitive impairments in Parkinson's disease (PD) often coexist and are prognostic of adverse health events. Consequently, assessment and training that simultaneously address both gait function and cognition are important to consider in rehabilitation and promotion of healthy aging. For this purpose, a computer game-based rehabilitation treadmill platform (GRP) was developed for dual-task (DT) assessment and training. OBJECTIVE: The first objective was to establish the test-retest reliability of the GRP assessment protocol for DT gait, visuomotor and executive cognitive function in PD patients. The second objective was to examine the effect of task condition [single task (ST) vs. DT] and disease severity (stage 2 vs. stage 3) on gait, visuomotor and cognitive function. METHODS: Thirty individuals aged 55 to 70 years, diagnosed with PD; 15 each at Hoehn and Yahr scale stage 2 (PD-2) and 3 (PD-3) performed a series of computerized visuomotor and cognitive game tasks while sitting (ST) and during treadmill walking (DT). A treadmill instrumented with a pressure mat was used to record center of foot pressure and compute the average and coefficient of variation (COV) of step time, step length, and drift during 1-min, speed-controlled intervals. Visuomotor and cognitive game performance measures were quantified using custom software. Testing was conducted on two occasions, 1 week apart. RESULTS: With few exceptions, the assessment protocol showed moderate to high intraclass correlation coefficient (ICC) values under both ST and DT conditions for the spatio-temporal gait measures (average and COV), as well as the visuomotor tracking and cognitive game performance measures. A significant decline in gait, visuomotor, and cognitive game performance measures was observed during DT compared to ST conditions, and in the PD-3 compared to PD-2 groups. CONCLUSION: The high to moderate ICC values along with the lack of systematic errors in the measures indicate that this tool has the ability to repeatedly record reliable DT interference (DTI) effects over time. The use of interactive digital media provides a flexible method to produce and evaluate DTI for a wide range of executive cognitive activities. This also proves to be a sensitive tool for tracking disease progression. CLINICAL TRIAL REGISTRATION: www.ClinicalTrials.gov, identifier NCT03232996.

Changes in Metabolic Activity and Gait Function by Dual-Task Cognitive Game-Based Treadmill System in Parkinson's Disease: Protocol of a Randomized Controlled Trial.

Balance and gait impairments, and consequently, mobility restrictions and falls are common in Parkinson's disease (PD). Various cognitive deficits are also common in PD and are associated with increased fall risk. These mobility and cognitive deficits are limiting factors in a person's health, ability to perform activities of daily living, and overall quality of life. Community ambulation involves many dual-task (DT) conditions that require processing of several cognitive tasks while managing or reacting to sudden or unexpected balance challenges. DT training programs that can simultaneously target balance, gait, visuomotor, and cognitive functions are important to consider in rehabilitation and promotion of healthy active lives. In the proposed multi-center, randomized controlled trial (RCT), novel behavioral positron emission tomography (PET) brain imaging methods are used to evaluate the molecular basis and neural underpinnings of: (a) the decline of mobility function in PD, specifically, balance, gait, visuomotor, and cognitive function, and (b) the effects of an engaging, game-based DT treadmill walking program on mobility and cognitive functions. Both the interactive cognitive game tasks and treadmill walking require continuous visual attention, and share spatial processing functions, notably to minimize any balance disturbance or gait deviation/stumble. The ability to "walk and talk" normally includes activation of specific regions of the prefrontal cortex (PFC) and the basal ganglia (site of degeneration in PD). The PET imaging analysis and comparison with healthy age-matched controls will allow us to identify areas of abnormal, reduced activity levels, as well as areas of excessive activity (increased attentional resources) during DT-walking. We will then be able to identify areas of brain plasticity associated with improvements in mobility functions (balance, gait, and cognition) after intervention. We expect the gait-cognitive training effect to involve re-organization of PFC activity among other, yet to be identified brain regions. The DT mobility-training platform and behavioral PET brain imaging methods are directly applicable to other diseases that affect gait and cognition, e.g., cognitive vascular impairment, Alzheimer's disease, as well as in aging.

Reliability and validity of a computer game-based tool of upper extremity assessment for object manipulation tasks in children with cerebral palsy.

INTRODUCTION: A computer game-based upper extremity (CUE) assessment tool is developed to quantify manual dexterity of children with Cerebral Palsy (CP). The purpose of this study was to determine test-retest reliability of the CUE performance measures (success rate, movement onset time, movement error, and movement variation) and convergent validity with the Peabody Developmental Motor Scale version 2 (PDMS-2) and the Quality of Upper Extremity Skills Test (QUEST). METHODS: Thirty-five children with CP aged four to ten years were tested on two occasions two weeks apart. RESULTS: CUE performance measures of five chosen object manipulation tasks exhibited high to moderate intra-class correlation coefficient (ICC) values. There was no significant difference in the CUE performance measures between test periods. With few exceptions, there was no significant correlation between the CUE performance measures and the PDMS-2 or the QUEST test scores. CONCLUSIONS: The high to moderate ICC values and lack of systematic errors indicate that the CUE assessment tool has the ability to repeatedly record reliable performance measures of different object manipulation tasks. The lack of a correlation between the CUE and the PDMS-2 or QUEST scores indicates that performance measures of these assessment tools represent distinct attributes of manual dexterity.

Parents' Perspectives on a Computer Game-Assisted Rehabilitation Program for Manual Dexterity in Children With Cerebral Palsy: Qualitative Analysis of Expectations, Child Engagement, and Benefits.

BACKGROUND: Children with motor impairments affecting the upper extremity benefit from task-specific therapy, such as constraint-induced movement therapy. However, there is a need to improve engagement and compliance with task-specific exercise programs that target manual dexterity for children with cerebral palsy (CP). A computer game-based rehabilitation (GRP) platform was developed that combines fine manipulation and gross movement exercises with engaging game activities appropriate for young children with CP. OBJECTIVE: The objectives of this qualitative analysis were to compare parents' perspectives and opinions about expectations, challenges, and benefits between 2 interventions. METHODS: A mixed methods, randomized controlled trial (RCT) was conducted to examine the feasibility and estimate the effect size of 2 exercise programs for rehabilitation of manual dexterity of children with CP using either GRP or conventional therapy. Parents of 26 of the children who completed the GRP program (n=33) and parents of 15 of the children who completed the conventional therapy program (n=27) participated in the interviews. A general conductive approach was used to analyze the data recorded during the parents' interviews. RESULTS: Five themes captured the range of the parent's experiences, viewpoints, and ideas: (1) parents' expectations, (2) child's engagement with therapy, (3) positive effects of the interventions, (4) challenges, and (5) improving the protocol. CONCLUSIONS: Parents from both groups recognized that their expectations related to improving children's object handling and manipulation skills including participation in activities of daily life were addressed during the 16-week therapy program. Parents perceived a change in the children's level of independence in their daily tasks at home, school, and leisure activities. TRIAL REGISTRATION: ClinicalTrials.gov NCT02728375; https://clinicaltrials.gov/ct2/show/NCT02728375.

Evaluation of a Game Based Tele Rehabilitation Platform for In-Home Therapy of Hand-Arm Function Post Stroke: Feasibility Study.

BACKGROUND: There is a need for innovation to improve compliance and accessibility of rehabilitation programs for individuals with acquired brain injuries. A computer game-assisted tele-rehabilitation platform (GTP) has been developed to address this need. With the novel application of a miniature inertial computer mouse and taking advantage of the wide variety of computer games, the GTP can provide engaging exercises for rehabilitation of upper extremity motor skills. OBJECTIVE: To determine the feasibility and acceptability of the game-assisted home exercise program for upper extremity rehabilitation for people with stroke. The treatment effect was also measured after 16 weeks of intervention. DESIGN: A feasibility study. SETTING: College of Rehabilitation Science, University of Manitoba. PARTICIPANTS: Ten stroke clients. INTERVENTION: Participants received three to four initial clinically supervised therapy sessions for training with the game assisted therapy program. Once trained, participants continued the program at the home for 16 weeks, four times per week. MAIN OUTCOME MEASURES: Feasibility was evaluated based on retention rate and compliance. Semistructured interviews after the completion of the program were done to assess acceptability of the program. Quantitative analysis included (1) the Wolf Motor Function Test A and B and (2) a computerized performance-based assessment of specific object manipulation tasks that required a combination of finger, wrist, elbow and shoulder motion. RESULTS: Findings demonstrated the feasibility and acceptability of the home tele-rehab program. Eight of the 10 participants fully complied with the 16-week exercise program. Two participants had difficulty with computer operations and did not complete the program. For the eight participants who completed the program, there was a substantial improvement from pre- to postintervention. CONCLUSION: Although some difficulties with the technology were reported, the findings demonstrate feasible trial procedures, acceptable game-assisted task-oriented home training with a high compliance rate and positive outcomes. These findings and the theoretical evidence direct the next phase of a full-scale randomized controlled trial.

Dual-Task Training Program for Older Adults: Blending Gait, Visuomotor and Cognitive Training.

Objective: Physical and cognitive impairments are common with aging and often coexist. Changes in the level of physical and mental activity are prognostic for adverse health events and falls. Dual-task (DT) training programs that can improve mobility and cognition simultaneously can bring significant improvements in rehabilitation. The objective of this mixed methods exploratory RCT was to provide evidence for the feasibility and therapeutic value of a novel game-assisted DT exercise program in older adults. Methods: Twenty-two community dwelling participants, between the ages of 70-85 were randomized to either dual-task treadmill walking (DT-TR) or dual-task recumbent bicycle (DT-RC). Both groups viewed a standard LED computer monitor and performed a range of cognitive game tasks while walking or cycling; made possible with the use of a "hands-free", miniature, inertial-based computer mouse. Participants performed their respective 1-h DT exercise program twice a week, for 12 weeks at a community fitness centre. Semi-structured interviews and qualitative analysis was conducted to evaluate the participant's experiences with the exercise program. Quantitative analysis included measures of standing balance, gait function (spatiotemporal gait variable), visuomotor and executive cognitive function, tested under single and DT walking conditions. Results: Compliance was 100% for all 22 participants. Four themes captured the range of participant's experiences and opinions: 1) reasons for participation, 2) difficulties with using the technologies, 3) engagement with the computer games, and 4) positive effects of the program. Both groups showed significant improvements in standing balance performance, visuomotor and visuospatial executive function. However, significant improvement in dual task gait function was observed only in the DT-TR group. Medium to large effect sizes were observed for most balance, spatiotemporal gait variables, and cognitive performance measure. Conclusion: With only minor difficulties with the technology being reported, the findings demonstrate feasible trial procedures and acceptable DT oriented training with a high compliance rate and positive outcomes. These findings support further research and development, and will direct the next phase of a full-scale RCT.

Imaging Cerebral Glucose Metabolism during Dual-Task Walking in Patients with Parkinson's disease.

BACKGROUND AND PURPOSE: Gait impairment is a hallmark of Parkinson's disease (PD). Natural walking involves more cognitive demand than treadmill walking or in-laboratory walking tests because patients have to actively work on navigation and top-down cognitive control which taxes cognitive reserve in the prefrontal cortex. To mimic the prefrontal engagement occurring with natural walking in a controlled and safe environment, dual-task (DT) treadmill walking has been developed. In this study, we tested the feasibility of imaging DT walking-related changes in brain glucose metabolism in patients with PD. METHODS: Fifteen patients with PD were scanned with fluorodeoxyglucose (FDG) positron emission tomography. Five patients performed DT walking, and 10 patients were rested during the FDG uptake period. First, the images were contrasted between the groups. Second, the walking-related brain glucose metabolism was inspected at the individual level. RESULTS: Consistently increased glucose metabolism was identified in DT walking versus rest in the primary visual/sensorimotor areas, thalamus, superior colliculus, and cerebellum. In individual level analysis, patients with less progressed disease (n = 3) showed prefrontal activity during DT walking while patients with more progressed disease (n = 2) did not. CONCLUSION: This study confirms the feasibility of imaging glucose metabolism during DT walking in patients with PD. We also report that during DT walking, there is a lesser degree of prefrontal engagement in the patients with more progressed disease compared to those with less progressed disease, implying increased degrees of frontal dysfunction with PD progression.

Comparison of selected measures of gait stability derived from center of pressure displacement signal during single and dual-task treadmill walking.

Steady state gait dynamics has been examined using the measures of regularity, local dynamic stability, and variability. This study investigates the relationship between these measures under increasing cognitive loads. Participants walked on an instrumented treadmill at 1 m/s under walk only and two dual-task conditions. The secondary tasks were visuomotor cognitive games (VCG) of increasing difficulty level. The center of pressure displacement in the mediolateral direction (ML COP-D) and cognitive game performance were recorded for analysis. The following measures were calculated: (1) sample entropy (SampEn) and quantized dynamical entropy (QDE) of the ML COP-D, (2) short-term largest Lyapunov exponent (LLE) of the ML COP-D, and (3) variability of inter-stride spatio-temporal gait variables. Entropy and variability measures significantly increased from walk only to both dual-task conditions. Whereas, the short-term LLE increased only during the easy VCG task. No measure was sensitive to the difficulty level of the VCG tasks. The variability of heel strike positions in the mediolateral direction was positively correlated with SampEn and QDE. However, there were no significant correlations between the short-term LLE and either variability measures or entropy measures. These findings confirm that each of these measures is representative of a different aspect of human gait dynamics.

Brain gray matter volume associations with gait speed and related structural covariance networks in cognitively healthy individuals and in patients with mild cognitive impairment: A cross-sectional study.

INTRODUCTION: Gait speed is slower in patients with mild cognitive impairment (MCI) compared to cognitively healthy individuals (CHI). We examined the patterns of brain gray matter (GM) volume association and covariance with gait speed in CHI and in patients with MCI. METHODS: A total of 96 CHI and 99 patients with MCI were recruited in this cross-sectional study. Brain GM volumes measured with voxel-based morphometry and self-paced gait speed were used as outcomes. RESULTS: The right middle frontal and precentral gyri volumes were positively associated with gait speed in CHI and covariated with frontal cortex. Striatum (i.e. left putamen and bilateral caudate nuclei) volumes were positively associated with gait speed in patients with MCI and covariated with striatal structures. CONCLUSIONS: Two different patterns of brain GM volume association and covariance with gait speed were found and involving frontal cortex in CHI and the striatum in patients with MCI.

Motoric cognitive risk syndrome, incident cognitive impairment and morphological brain abnormalities: Systematic review and meta-analysis.

BACKGROUND: Motoric cognitive risk syndrome (MCR) is a pre-dementia stage, which associates slow walking speed with subjective cognitive impairment (SCI). MCR's clinical utility for the prediction of dementia and its pathophysiology are unclear. The aim of this systematic review and meta-analysis is to examine the association of MCR with incident cognitive impairment, cognitive performance and brain structures. METHODS: A systematic search was conducted using the Medical Subject Heading terms "Walking" and "Cognition disorders" combined with the terms "Subjective cognitive impairment", "Subjective cognitive decline" and "Motoric cognitive risk". A total of 11 studies were included in the systematic review and meta-analysis: 3 studies had dementia as the outcome, 3 studies had cognitive performance as the outcome, 4 studies had brain structures as the outcome and one study examined the incidence of both major neurocognitive disorders and cognitive impairment. RESULTS: MCR was found to be associated with incident cognitive impairment (pooled hazard ratio (HR) = 1.70, 95% CI, 1.46-1.98 with P-value <0.001) and dementia (pooled HR = 2.50, 95% CI, 1.75-2.39 with P-value <0.001). MCR was also found to be associated with low grey matter volume involving the premotor and the prefrontal cortex, and lacunar lesions in the frontal lobe. No significant association was found with white matter abnormalities. CONCLUSION: MCR predicts cognitive impairment and dementia, suggesting that it may be used as a screening syndrome for dementia in a primary care setting. Its significant association with both low grey matter volume and lacunar lesions makes its pathophysiology unclear and suggests multiple pathways.

Association of Motoric Cognitive Risk Syndrome with Cardiovascular Disease and Risk Factors: Results from an Original Study and Meta-Analysis.

BACKGROUND: Motoric cognitive risk (MCR) syndrome, a recently described pre-dementia syndrome, has been associated with cardiovascular disease and their risk factors (CVDRF). OBJECTIVE: To determine whether MCR syndrome was associated with CVDRF in French community-dwelling older adults, and to quantitatively evaluate, with a systematic review and meta-analysis, the association of MCR syndrome with CVDRF. METHODS: Based on a cross-sectional design, 238 older adults without dementia were selected from the French GAIT study. An English and French systematic Medline and Embase search (without limiting date of publication) was also conducted in February 2017 using the terms "motoric cognitive risk syndrome" OR "motoric cognitive risk" OR "motoric risk". The systematic review and meta-analysis included 8 studies. CVDRF were defined as cardiovascular diseases, hypertension, diabetes, stroke, obesity and abnormal waist-hip ratio (WHR). RESULTS: The prevalence of MCR syndrome in the current original study was 16.8%. MCR syndrome was associated with abnormalWHR(Odds ratio [OR] >2.8 with p < 0.020) and high blood pressure (OR >2.5 with p < 0.025). Of the 202 originally identified abstracts, 7 (3.5%) were selected for the systematic review. The meta-analysis showed that all pooled OR were significant with a p-value <0.001 (OR = 1.41 for cardiovascular diseases, 1.21 for hypertension, 1.44 for diabetes, 2.05 for stroke, and 1.34 for obesity). When pooling all CVDRF, the overall OR was 1.38 (95% CI, 1.33-1.45) with p-value <0.001. CONCLUSION: MCR syndrome is significantly associated with CVDRF. These findings suggest that a vascular mechanism may underlie the pathophysiology of MCR syndrome.

Sample Entropy of Human Gait Center of Pressure Displacement: A Systematic Methodological Analysis.

Sample entropy (SampEn) has been used to quantify the regularity or predictability of human gait signals. There are studies on the appropriate use of this measure for inter-stride spatio-temporal gait variables. However, the sensitivity of this measure to preprocessing of the signal and to variant values of template size (m), tolerance size (r), and sampling rate has not been studied when applied to "whole" gait signals. Whole gait signals are the entire time series data obtained from force or inertial sensors. This study systematically investigates the sensitivity of SampEn of the center of pressure displacement in the mediolateral direction (ML COP-D) to variant parameter values and two pre-processing methods. These two methods are filtering the high-frequency components and resampling the signals to have the same average number of data points per stride. The discriminatory ability of SampEn is studied by comparing treadmill walk only (WO) to dual-task (DT) condition. The results suggest that SampEn maintains the directional difference between two walking conditions across variant parameter values, showing a significant increase from WO to DT condition, especially when signals are low-pass filtered. Moreover, when gait speed is different between test conditions, signals should be low-pass filtered and resampled to have the same average number of data points per stride.

The Effects of Aging and Dual Tasking on Human Gait Complexity During Treadmill Walking: A Comparative Study Using Quantized Dynamical Entropy and Sample Entropy.

Quantized dynamical entropy (QDE) has recently been proposed as a new measure to quantify the complexity of dynamical systems with the purpose of offering a better computational efficiency. This paper further investigates the viability of this method using five different human gait signals. These signals are recorded while normal walking and while performing secondary tasks among two age groups (young and older age groups). The results are compared with the outcomes of previously established sample entropy (SampEn) measure for the same signals. We also study how analyzing segmented and spatially and temporally normalized signal differs from analyzing whole data. Our findings show that human gait signals become more complex as people age and while they are cognitively loaded. Center of pressure (COP) displacement in mediolateral direction is the best signal for showing the gait changes. Moreover, the results suggest that by segmenting data, more information about intrastride dynamical features are obtained. Most importantly, QDE is shown to be a reliable measure for human gait complexity analysis.

Guidelines for Assessment of Gait and Reference Values for Spatiotemporal Gait Parameters in Older Adults: The Biomathics and Canadian Gait Consortiums Initiative.

Background: Gait disorders, a highly prevalent condition in older adults, are associated with several adverse health consequences. Gait analysis allows qualitative and quantitative assessments of gait that improves the understanding of mechanisms of gait disorders and the choice of interventions. This manuscript aims (1) to give consensus guidance for clinical and spatiotemporal gait analysis based on the recorded footfalls in older adults aged 65 years and over, and (2) to provide reference values for spatiotemporal gait parameters based on the recorded footfalls in healthy older adults free of cognitive impairment and multi-morbidities. Methods: International experts working in a network of two different consortiums (i.e., Biomathics and Canadian Gait Consortium) participated in this initiative. First, they identified items of standardized information following the usual procedure of formulation of consensus findings. Second, they merged databases including spatiotemporal gait assessments with GAITRite® system and clinical information from the "Gait, cOgnitiOn & Decline" (GOOD) initiative and the Generation 100 (Gen 100) study. Only healthy-free of cognitive impairment and multi-morbidities (i.e., ≤ 3 therapeutics taken daily)-participants aged 65 and older were selected. Age, sex, body mass index, mean values, and coefficients of variation (CoV) of gait parameters were used for the analyses. Results: Standardized systematic assessment of three categories of items, which were demographics and clinical information, and gait characteristics (clinical and spatiotemporal gait analysis based on the recorded footfalls), were selected for the proposed guidelines. Two complementary sets of items were distinguished: a minimal data set and a full data set. In addition, a total of 954 participants (mean age 72.8 ± 4.8 years, 45.8% women) were recruited to establish the reference values. Performance of spatiotemporal gait parameters based on the recorded footfalls declined with increasing age (mean values and CoV) and demonstrated sex differences (mean values). Conclusions: Based on an international multicenter collaboration, we propose consensus guidelines for gait assessment and spatiotemporal gait analysis based on the recorded footfalls, and reference values for healthy older adults.

The interacting effects of treadmill walking and different types of visuospatial cognitive task: Discriminating dual task and age effects.

OBJECTIVE: The objective of this study is to examine the influence that visuospatial cognitive tasks have on gait function during DT treadmill walking, and as a function of age. Conversely, to examine the influence that walking has on executive functions involving visuospatial processing. METHODS: Twenty-five young (26±6.1years) and 25 older adults (76±3.9) performed different types of computerized visuomotor (VM) tracking and visuospatial cognitive tasks (VCG) while standing and treadmill walking. Spatiotemporal gait variables, average values and co-efficient of variation (COV) were obtained from 40 consecutive steps during single- and dual-task walk trials. Performance-based measures of the VM and VCG task were obtained during standing and walking. RESULTS: VM dual-task walking had a significant effect on gait measures in the young age group (YG), but no DT effect was observed in the old age group (OG). Visuomotor tracking performance, however, was significantly reduced in the OG as compared to the YG when tested in both standing and walking. The opposite was true for VCG; a significant DT effect on gait performance was observed in the OG, but no DT effect was observed in the YG. Success rate of the VCG task decreased during walking, but only for OG. CONCLUSION: Controlling gait speed and objective evaluation of the visuospatial cognitive tasks helps to determine the level of engagement in the DT tasks. This is important in order to determine the strategies used during the DT test protocols, i.e. cross-domain interference.