Functional Lower Extremity Strength Influences Stepping Strategy in Community-Dwelling Older Adults During Single and Dual-Task Walking

As age increases, a decline in lower extremity strength leads to reduced mobility and increased fall risks. This decline outpaces the age-related reduction in muscle mass, resulting in mobility limitations. Older adults with varying degrees of mobility-disability use different stepping strategies. However, the link between functional lower extremity strength and stepping strategy is unknown. Therefore, understanding how age-related reductions in functional lower extremity strength influence stepping strategy is vital to unraveling mobility limitations. Participants were recruited and tested at a local community event, where they were outfitted with IMUs and walked across a pressurized walkway. Our study reveals that older adults with normal strength prefer adjusting their step time during walking tasks, while those with reduced strength do not exhibit a preferred stepping strategy. This study provides valuable insights into the influence of functional lower extremity strength on stepping strategy in community-dwelling older adults during simple and complex walking tasks. These findings could aid in diagnosing gait deviations and developing appropriate treatment or management plans for mobility disability in older adults.

Evaluating Cognitive-Motor Interference in Multiple Sclerosis: A Technology-Based Approach

BACKGROUND

People with multiple sclerosis (PwMS) frequently present both cognitive and motor impairments, so it is reasonable to assume they may have difficulties in executing dual-tasks (DT). The aim of the present study is to identify novel technology-based parameters to assess cognitive-motor interference (CMI) in PwMS. In particular, we focused on the definition of dual-task cost (DTC) measures using wearable and portable tools such as insoles and mobile apps.

METHODS

All participants underwent a verbal fluency task (cognitive single-task, ST), a motor ST of walking, and a combination of these tasks (DT). Number of words uttered in the cognitive ST and steps recorded by insoles were used to calculate the motor and cognitive DTC.

RESULTS

The number of steps strongly correlated with the walked meters for both single- (r = 0.88, p < 0.05) and dual- (r = 0.91, p < 0.05) tasks. Motor but not cognitive performances significantly worsened during DT. Over the cognitive ST and DT, the number of pronounced words progressively decreased, probably due to the activation of different cognitive processes. Cognitive efforts could be the cause of cognitive task prioritization.

CONCLUSIONS

Our findings promote the use of low-cost devices to assess CMI easily in the clinical context and to detect ecologically valid DT impairments.

The effects of cognitive-motor dual-task training on athletes' cognition and motor performance

Background

Cognitive-Motor Dual Task (CMDT) training has been widely utilized in rehabilitation and sports practice. However, whether CMDT training can better enhance athletes' cognitive-motor performance compared to traditional single-task (ST) training remains unclear.

Method

A systematic review that complied with PRISMA was carried out (Prospero registration number: CRD42023443594). The electronic databases used for the systematic literature search from the beginning through 13 June 2023, included Web of Science, Embase, PubMed, and the Cochrane Library. After obtaining the initial literature, two researchers independently assessed it based on inclusion and exclusion criteria. Finally, the included literature was analyzed to compare the differences between ST training and CMDT training.

Results

After screening 2,094 articles, we included 10 acute studies and 7 chronic studies.

Conclusion

This systematic review shows that athletes typically show a degradation of performance in CMDT situations as opposed to ST when evaluated transversally. However, this performance decline is notably reduced following longitudinal training in CMDT, indicating the effectiveness of sustained CMDT training in enhancing cognitive-motor performance under dual-task conditions. Our study provides new insights into the application of CMDT in the field of sports training. Practitioners can utilize CMDT to assess athletic skill levels or optimize cognitive-motor performance of athletes, taking into account the specific needs of each sport.

Systematic review registration

https://www.crd.york.ac.uk/prospero, identifier CRD42023443594.

The Effects of Various Cognitive Tasks Including Working Memory, Visuospatial, and Executive Function on Postural Control in Patients With Anterior Cruciate Ligament Injury

Anterior cruciate ligament (ACL) rupture can impair balance performance, particularly during cognitive motor dual-tasks. This study aimed to determine the effects of various modalities of cognitive load (working memory, and visuospatial and executive function) on postural control parameters in individuals with ACL injury. Twenty-seven ACL-injured and 27 healthy participants were evaluated doing different cognitive tasks (silent backward counting, Benton's judgment of line orientation, and Stroop color-word test) while standing on a rigid surface or a foam. Each task was repeated three times and then averaged. Center of pressure variables used to measure postural performance included sway area and sway velocity in anterior-posterior and medial-lateral directions. Cognitive performance was also assessed by calculating errors and the score of cognitive tasks. A mixed model analysis of variance for center of pressure parameters indicated that patients had more sways than the healthy group. The interaction of group by postural difficulty by cognitive tasks was statistically significant for cognitive errors (p < .01), and patients with ACL injury indicated more cognitive errors compared to healthy controls while standing on the foam. The main effect of cognitive task was statistically significant for all postural parameters, representing reduced postural sways in both groups with all cognitive tasks. However, ACL-injured patients showed more cognitive errors in difficult postural conditions, suggesting that individuals with ACL injury may prioritize postural control over cognitive task accuracy and adopt the posture-first strategy to maintain balance under dual-task conditions.

Effectiveness and cost of integrated cognitive and balance training for balance and falls in cerebellar ataxia: a blinded two-arm parallel group RCT

Background

In patients with cerebellar ataxia (CA), dual-tasking deteriorates the performance of one or both tasks.

Objective

Evaluate the effects of 4 weeks of cognitive-coupled intensive balance training (CIBT) on dual-task cost, dynamic balance, disease severity, number of falls, quality of life, cognition and cost among patients with CA.

Methods

This RCT compared CIBT (Group 1) to single-task training (Group 2) among 32 patients with CA. The intervention included either dual-task (CIBT) or single-task training for 4 weeks followed by 6 months of unsupervised home exercises. Dual-task timed up-and-go test (D-TUG) assessed dual-task cost of the physical and cognitive tasks. Assessment time points included baseline 1 (Week 0:T1), baseline 2 (Week 6:T2), post-intervention (Week 10:T3), and follow-up (Week 34:T4).

Results

Compared to single-task training CIBT improved the dual-task cost of physical task [MD -8.36 95% CI (-14.47 to -2.36, p < 0.01), dual-tasking ability [-6.93 (-13.16 to -0.70); p = 0.03] assessed using D-TUG, balance assessed using the scale for the assessment and rating of ataxia (SARAbal) [-2.03 (-4.04 to -0.19); p = 0.04], visual scores of the SOT (SOT-VIS) [-18.53 (-25.81 to -11.24, p ≤ 0.01] and maximal excursion [13.84 (4.65 to 23.03; p ≤ 0.01] of the Limits of Stability (LOS) in the forward direction and reaction time in both forward [-1.11 (-1.42 to -0.78); p < 0.01] and right [-0.18 (0.05 to 0.31); p < 0.01] directions following 4 weeks of training. CIBT did not have any additional benefits in reducing the number of falls, or improving disease severity, quality of life and cognition. The mean cost of intervention and healthcare costs for 7 months was HKD 33,380 for CIBT group and HKD 38,571 for single-task training group.

Conclusion

We found some evidence to support the use of CIBT for improving the dual-tasking ability, dual-task cost of physical task and dynamic balance in CA. Future large fully-powered studies are needed to confirm this claim.

Clinical trial registration

https://clinicaltrials.gov/study/NCT04648501, identifier [Ref: NCT04648501].

Sensitivity, reliability and convergent validity of sequential dual-task measures of listening effort

OBJECTIVE

The aim of the current study was to assess the sensitivity, reliability and convergent validity of objective measures of listening effort collected in a sequential dual-task.

DESIGN

On each trial, participants viewed a set of digits and listened to a spoken sentence presented at one of a range of signal-to-noise ratios (SNR) and then typed the sentence-final word and recalled the digits. Listening effort measures included word response time, digit recall accuracy and digit response time. In Experiment 1, SNR on each trial was randomised. In Experiment 2, SNR varied in a blocked design, and in each block self-reported listening effort was also collected.

STUDY SAMPLES

Separate groups of 40 young adults participated in each experiment.

RESULTS

Effects of SNR were observed for all measures. Linear effects of SNR were generally observed even with word recognition accuracy factored out of the models. Among the objective measures, reliability was excellent, and repeated-measures correlations, though not between-subjects correlations, were nearly all significant.

CONCLUSION

The objective measures assessed appear to be sensitive and reliable indices of listening effort that are non-redundant with speech intelligibility and have strong within-participants convergent validity. Results support use of these measures in future studies of listening effort.

Cognitive CAMSA: an ecological proposal to integrate cognitive performance into motor competence assessment

Purpose

To profile the participants using a system of self-organizing maps (SOM) based on their motor and cognitive performance during a dual-task version of the Canadian Agility and Movement Skill Assessment (Cognitive CAMSA).

Methods

A total of 169 secondary school students (39.3% girls) volunteered to participate. The original CAMSA, cognitive CAMSA, the Corsi and Digit Span tests were used to assess (a) motor competence, (b) motor competence with cognitive load, and (c) cognitive performance, respectively. SOMs and the k-means clustering algorithm were used to establish the adolescents' dual-task performance profiles.

Results

Including decision making based on verbal and visual cues in the original CAMSA significantly increased the participants' total scores but also the time required to complete the test, while the skill score remained unchanged. However, not all the participants showed changes in their performance in the same direction during the cognitive CAMSA. Person-centered analyses by SOMs and k-means clustering identified six performance profiles with variations in the cognitive, motor skill, and time scores (H5 = 146.15, H5 = 102.68, and H5 = 108.07, respectively; all p < 0.01).

Conclusion

The cognitive CAMSA was shown to be a feasible field-motor test for assessing motor competence with a cognitive load in an ecological setting. Some of the profiles identified in the SOM approach represented adolescents with similar motor and cognitive performance in dual-task or single-task contexts, although other participants obtained high motor competence in single and dual-tasking while their cognitive performance declined or rose more in dual-task than in single task situations. The cognitive CAMSA emerges as a tool of great potential, applicable in educational and sports environments, to know subjects' characteristics and try to individualize the interventions accordingly with their dual-task profile.

Dual-task difficulties as a risk factor for unemployment in people with multiple sclerosis

BACKGROUND

No study has investigated the impact of dual-tasking difficulties as a risk factor for unemployment in people with multiple sclerosis (pwMS). The aim was to examine the influence of dual-task performance on employment status and work difficulties and to identify the predictors of employment status in pwMS.

METHODS

Eighty-four pwMS, including 42 employed and 42 unemployed, participated in the study. Dual-task difficulties were assessed using the Dual-task Impact on Daily-living Activities-Questionnaire (DIDA-Q), while dual-task performance was evaluated through the 30-second Walk Test and Nine-Hole Peg Test, incorporating a cognitive task. Walking and cognitive function were also measured.

RESULTS

Employed pwMS had better scores in walking, cognitive function, single and dual-task performance than unemployed pwMS (p < .05). Lower scores in walking (odds ratio [OR] = 1.81, p < .001) and upper extremity-related (OR = 1.44, p = .019) dual-task performance and higher scores in the cognitive subscale of the DIDA-Q questionnaire (OR = 1.20, p = .037) were significantly associated with higher odds of being unemployed. Among employed pwMS, DIDA-Q subscales showed moderate-to-strong correlations with MSWSDQ-23 scores. The other variables showed weak-to-moderate correlations with subscale and total scores of MSWSDQ-23.

CONCLUSION

Cognitive function, as opposed to motor function, has been found to be a significant predictor of unemployment in pwMS.

Fronto-parietal theta high-definition transcranial alternating current stimulation may modulate working memory under postural control conditions in young healthy adults

Objects

This study aimed to investigate the immediate effects of fronto-parietal θ HD-tACS on a dual task of working memory-postural control.

Methods

In this within-subject cross-over pilot study, we assessed the effects of 20 min of 6 Hz-tACS targeting both the left dorsolateral prefrontal cortex (lDLPFC) and posterior parietal cortex (PPC) in 20 healthy adults (age: 21.6 ± 1.3 years). During each session, single- and dual-task behavioral tests (working memory single-task, static tandem standing, and a dual-task of working memory-postural control) and closed-eye resting-state EEG were assessed before and immediately after stimulation.

Results

Within the tACS group, we found a 5.3% significant decrease in working memory response time under the dual-task following tACS (t = -3.157, p = 0.005, Cohen's d = 0.742); phase synchronization analysis revealed a significant increase in the phase locking value (PLV) of θ band between F3 and P3 after tACS (p = 0.010, Cohen's d = 0.637). Correlation analyses revealed a significant correlation between increased rs-EEG θ power in the F3 and P3 channels and faster reaction time (r = -0.515, p = 0.02; r = -0.483, p = 0.031, respectively) in the dual-task working memory task after tACS. However, no differences were observed on either upright postural control performance or rs-EEG results (p-values <0.05).

Conclusion

Fronto-parietal θ HD-tACS has the potential of being a neuromodulatory tool for improving working memory performance in dual-task situations, but its effect on the modulation of concurrently performed postural control tasks requires further investigation.

Associations Between Cognitive Function and ACL Injury-Related Biomechanics: A Systematic Review

CONTEXT

Does lower baseline cognitive function predispose athletes to ACL injury risk, especially when performing unplanned or dual-task movements?

OBJECTIVE

To evaluate the association between cognitive function and biomechanics related to ACL injuries during cognitively challenging sports movements.

DATA SOURCES

PubMed (MEDLINE), Web of Science, Scopus, and SciELO databases were searched; additional hand searching was also conducted.

STUDY SELECTION

The following inclusion criteria had to be met: participants completed (1) a neurocognitive test, (2) a cognitively challenging sport-related task involving lower limbs, and (3) a biomechanical analysis. The following criteria determined exclusion from the review: studies involving participants with (1) recent or current musculoskeletal injuries; (2) recent or current concussion; (3) ACL surgical reconstruction, reviews of the literature, commentary or opinion articles, and case studies.

STUDY DESIGN

Systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA-P) statement and registered at the International Prospective Register of Systematic Reviews (PROSPERO).

LEVEL OF EVIDENCE

Level 3.

DATA EXTRACTION

Two of authors independently extracted data and assessed the methodological quality of the articles with the Downs and Black and ROBINS-I checklists, to assess methodological quality and risk of bias, respectively.

RESULTS

Six studies with different methodologies and confounding factors were included in this review. Of these 6 studies, 3 were ranked as high-quality, 3 demonstrated a low risk of bias, 2 a moderate risk, and 1 a severe risk. Five studies found a cognitive-motor relationship, with worse cognitive performance associated with increased injury risk, with 1 study reporting the opposite directionality for 1 variable. One study did not identify any interaction between cognitive function and biomechanical outcomes.

CONCLUSION

Worse cognitive performance is associated with an increased injury risk profile during cognitively challenging movements.

Aerobic physical exercise versus dual-task cognitive walking in cognitive rehabilitation of people with stroke: a randomized clinical trial

Introduction

Stroke is a neurological deficit caused by an acute focal injury to the central nervous system due to vascular injury that can result in loss of neurological function, lasting brain damage, long-term disability and, in some cases, death. The literature reports that aerobic physical exercise, as well as dual-task cognitive walking, are used for the cognitive recovery of people with stroke. We aimed to assess whether aerobic physical exercise influences post-stroke cognitive recovery, namely performance on selective and sustained attention. We tested the hypothesis that post-stroke aerobic physical exercise leads to more significant gains than post-stroke dual-task cognitive walking.

Methods

We used a Randomized Clinical Trial, single-blind, parallel group, to verify the existence of differences between two groups. A total of 34 patients with subacute to chronic stroke were divided into two groups to train three times a week for 12 weeks: the aerobic physical exercise (PE) group engaged in 20 min on a treadmill, 20 min on a stationary bicycle and 5 min on a desk bike pedal exerciser per session; the dual-task (DT) gait exercise group walked for 45 min while simultaneously performing cognitive tasks per session. All participants were assessed on cognitive functioning with the Mini-Mental State Examination (MMSE) and d2 Test of Attention before acute interventions and post interventions. We have also applied a Visual Analog Scale to monitor the participants' perceived difficulty, pre-, post-acute, and post-chronic interventions. Participants also responded to a Borg Scale of perceived exertion following the acute and the final session of chronic training.

Results

A mixed model ANOVA revealed a significant interaction effect with a large effect size for most of the cognitive variables under study. The variables associated with the d2 Test of Attention showed significant differences between the groups, mainly from T0 to T2. Also for MMSE, an ANOVA revealed a significant interaction effect with significant improvements from T0 to T2. Our results strongly suggest that aerobic physical exercise is more beneficial than dual-task cognitive-gait exercise since in the PE group, cognitive attention scores increase, and cognitive impairment and perception of exertion decrease, compared to the DT group.

Conclusion

These findings support that PE provides more significant benefits for patients post-stroke when compared to DT.

Implicit Motor Learning Strategies Benefit Dual-Task Performance in Patients with Stroke

Background and Objectives: In stroke rehabilitation, the use of either implicit or explicit learning as a motor learning approach during dual tasks is common, but it is unclear which strategy is more beneficial. This study aims to determine the benefits of implicit versus explicit motor learning approaches in patients with stroke. Materials and Methods: Seventeen patients with stroke and 21 control participants were included. Motor learning was evaluated using the Serial Reaction Time Task (SRTT) in the context of dual-task conditions. The SRTT was conducted on two separate days: one day for implicit learning conditions and the other day for explicit learning conditions. Under the explicit learning conditions, a task rule was given to the participants before they started the task, but not under the implicit learning conditions. Learning scores were calculated for both implicit and explicit learning, and these scores were then compared within groups for patients with stroke and controls. We calculated the difference in learning scores between implicit and explicit learning and conducted a correlation analysis with the Trail Making Test (TMT) Parts A and B. Results: Learning scores on the SRTT were not different between implicit and explicit learning in controls but were significantly greater in patients with stroke for implicit learning than for explicit learning. The difference in learning scores between implicit and explicit learning in patients with stroke was correlated with TMT-A and showed a correlation trend with TMT-B. Conclusions: Implicit learning approaches may be effective in the acquisition of motor skills with dual-task demands in post-stroke patients with deficits in attention and working memory.

A Randomized Clinical Trial to Evaluate a Digital Therapeutic to Enhance Gait Function in Individuals With Parkinson's Disease

BACKGROUND

Postural instability and gait dysfunction (PIGD) is a cardinal symptom of Parkinson's disease (PD) and is exacerbated under dual-task conditions. Dual-task training (DTT), enhances gait performance, however it is time and cost intensive. Digitizing DTT via the Dual-task Augmented Reality Treatment (DART) platform can expand the availability of an effective intervention to address PIGD.

OBJECTIVE

The aim of this project was to evaluate DART in the treatment of PIGD in people with PD compared to a Traditional DTT intervention. It was hypothesized that both groups would exhibit significant improvements in gait, and the improvements for the DART group would be non-inferior to Traditional DTT.

METHODS

A single-blind randomized controlled trial was conducted with 47 PD participants with PIGD. Both groups completed 16 therapeutic sessions over 8 weeks; the DART platform delivered DTT via the Microsoft HoloLens2. Primary outcomes included clinical ratings and single- and dual-task gait biomechanical outcomes.

RESULTS

Clinical measures of PD symptoms remained stable for DART and Traditional DTT groups. However, both groups exhibited a significant increase in gait velocity, cadence, and step length during single- and multiple dual-task conditions following the interventions. Improvements in gait velocity in the DART group were non-inferior to Traditional DTT under the majority of conditions.

CONCLUSION

Non-inferior improvements in gait parameters across groups provides evidence of the DART platform being an effective digital therapeutic capable of improving PIGD. Effective digital delivery of DTT has the potential to increase use and accessibility to a promising, yet underutilized and difficult to administer, intervention for PIGD.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Dual-task Augmented Reality Treatment for Parkinson's Disease (DART) NCT04634331; posted November 18, 2020.

Effective utilization of attentional resources in postural control in athletes of skill-oriented sports: an event-related potential study

Objective

Postural control plays a key role in skill-oriented sports. Athletes of skill-oriented sports (hereinafter referred to as "skilled athletes") usually showed better control ability compared with non-athletes. However, research focused on the single postural task, rarely considering the actual situation in skill-oriented sports in which other processes, such as cognitive control, frequently accompany postural control. This study aims to explore how skilled athletes control their posture under the dual-task situation and use limited attentional resources.

Method

A total of 26 skilled athletes and 26 non-athletes were required to perform the postural control and N-back tasks simultaneously. Center of pressure (COP) trajectory, reaction times (RTs), and discriminability (d') of N-back tasks were recorded and evaluated, along with event-related potentials, including N1 (Oz, PO7, and PO8), P2 (Fz, FCz, Cz, and Pz) components, and the spectral power of alpha band.

Results

Skilled athletes demonstrated more postural control stability and a higher d' than non-athletes in all dual tasks. Besides, they showed enhanced N1, P2 amplitudes and reduced alpha band power during dual-tasking. Notably, in skilled athletes, a significant negative correlation between N1 amplitude and d' was observed, while significant positive correlations between alpha band power and postural control performance were also identified.

Conclusion

This study investigates the potential advantages of skilled athletes in postural control from the view of neuroscience. Compared to non-athletes, skilled athletes could decrease the consumption of attentional resources in postural control and recruit more attentional resources in stimulus discrimination and evaluation in cognitive tasks. Since the allocation of attentional resources plays a crucial part in postural control in skilled athletes, optimizing the postural control training program and the selection of skilled athletes from a dual-task perspective is important.

Cerebral Cortex Activation and Gait Performance between Healthy and Prefrail Older Adults during Cognitive and Walking Tasks

Pre-frailty is a transitional stage between health and frailty. Previous studies have demonstrated that individuals with pre-frailty experience declines in cognitive and gait performances compared with healthy individuals. However, the basic neural mechanism underlying this needs to be clarified. In this cross-sectional study, twenty-one healthy older adults and fifteen with pre-frailty underwent three conditions, including a single cognitive task (SC), single walking task (SW), and dual-task (DT), while cortical hemodynamic reactions were measured using functional near-infrared spectroscopy (fNIRS). The prefrail group (PG) showed a significantly lower activation of the left dorsolateral prefrontal cortex (L-DLPFC) than the healthy group (HG) when performing SC (p < 0.05). The PG showed a significantly lower Timed Up and Go test and step speed than the HG during SW (p < 0.05). The coefficient of variation (CV) of the step length of the PG was significantly higher than that of the HG when performing DT (p < 0.05). No significant correlation in cerebral cortex activation and gait parameters in the HG when performing SW and DT was noted (p > 0.05). Participants of the PG with a higher oxygenated area in the left anterior prefrontal cortex (L-APFC) had a lower step frequency during SW (r = -0.533, p = 0.041), and so did the following indicators of the PG during DT: L-APFC and step speed (r = -0.557, p = 0.031); right anterior prefrontal cortex and step speed (r = -0.610, p = 0.016); left motor cortex and step speed (r = -0.674, p = 0.006); step frequency (r = -0.656, p = 0.008); and step length (r = -0.535, p = 0.040). The negative correlations between the cerebral cortex and gait parameters of the PG indicated a neural compensatory effect of pre-frailty. Therefore, older adults with pre-frailty promote prefrontal activation to compensate for the impaired sensorimotor systems.

Effect of agility ladder training with a cognitive task (dual task) on physical and cognitive functions: a randomized study

Introduction

Agility training (AT) is used to improve neuromuscular performance and dynamic balance, which are crucial for the physical function of older adults. Activities of daily living, which decrease with age, involve tasks that simultaneously require motor, and cognitive abilities and can be considered dual tasks.

Methods

This study investigates a training program's physical and cognitive effects using an agility ladder on healthy older adults. This program consisted of 30-min sessions twice per week and lasted for 14 weeks. The physical training included four different sequences with progressive difficulty levels, while the cognitive training (CT) included different verbal fluency (VF) tasks for each physical task. Sixteen participants (mean age of 66.9 ± 5.0 years) were allocated to two groups: AT alone (AT) and dual-task training (AT combined with CT [AT + CT]). Assessments were performed before and after 14 weeks of interventions using physical functional tests (e.g., Illinois agility test, five times sit-to-stand test, timed up and go [TUG], and one-leg stand) and cognitive tests (cognitive TUG, verbal fluency, attention, and scenery picture memory test).

Results

After this period, both groups had significant differences in physical performance, muscle power, agility, static and dynamic balance, and short-term memory, whereas only the AT + CT group improved phonological verbal fluency, executive function (TUG combined with a cognitive task), attention (trail-making test-B), and short-term memory (scenery picture memory test).

Conclusion

Indicating that only the group that received direct cognitive training had better enhanced cognitive function.

Clinical trial registration

www.ClinicalTrials.gov, identifier: RBR-7t7gnjk.

Dual-Task Performance, Balance and Aerobic Capacity as Predictors of Falls in Older Adults with Cardiovascular Disease: A Comparative Study

Cardiovascular diseases (CVD) are highly prevalent and strongly associated with the risk of falls in the elderly. Falls are associated with impairments in cognition and functional or gait performance; however, little is known about these associations in the elderly population with CVD. In this study, we aimed to clarify the possible associations of physical capacity and functional and cognitive outcomes with the incidence of falls in older adults with CVD. In this comparative study, 72 elderly patients were divided into fallers (n = 24 cases) and non-fallers (n = 48 controls) according to the occurrence of falls within one year. Machine learning techniques were adopted to formulate a classification model and identify the most important variables associated with the risk of falls. Participants with the worst cardiac health classification, older age, the worst cognitive and functional performance, balance and aerobic capacity were prevalent in the case group. The variables of most importance for the machine learning model were VO_2max, dual-task in seconds and the Berg Scale. There was a significant association between cognitive-motor performance and the incidence of falls. Dual-task performance, balance, and aerobic capacity levels were associated with an increased risk of falls, in older adults with CVD, during a year of observation.

Association of Dual-Task Gait Cost and White Matter Hyperintensity Burden Poststroke: Results From the ONDRI

BACKGROUND

Acute change in gait speed while performing a mental task [dual-task gait cost (DTC)], and hyperintensity magnetic resonance imaging signals in white matter are both important disability predictors in older individuals with history of stroke (poststroke). It is still unclear, however, whether DTC is associated with overall hyperintensity volume from specific major brain regions in poststroke.

METHODS

This is a cohort study with a total of 123 older (69 ± 7 years of age) participants with history of stroke were included from the Ontario Neurodegenerative Disease Research Initiative. Participants were clinically assessed and had gait performance assessed under single- and dual-task conditions. Structural neuroimaging data were analyzed to measure both, white matter hyperintensity (WMH) and normal appearing volumes. Percentage of WMH volume in frontal, parietal, occipital, and temporal lobes as well as subcortical hyperintensities in basal ganglia + thalamus were the main outcomes. Multivariate models investigated associations between DTC and hyperintensity volumes, adjusted for age, sex, years of education, global cognition, vascular risk factors, APOE4 genotype, residual sensorimotor symptoms from previous stroke and brain volume.

RESULTS

There was a significant positive global linear association between DTC and hyperintensity burden (adjusted Wilks' λ = .87, P = .01). Amongst all WMH volumes, hyperintensity burden from basal ganglia + thalamus provided the most significant contribution to the global association (adjusted β = .008, η² = .03; P = .04), independently of brain atrophy.

CONCLUSIONS

In poststroke, increased DTC may be an indicator of larger white matter damages, specifically in subcortical regions, which can potentially affect the overall cognitive processing and decrease gait automaticity by increasing the cortical control over patients' locomotion.

Effects of Mobile Phone Use on Gait and Balance Control in Young Adults: A Hip-Ankle Strategy

BACKGROUND

This study aimed to derive the effects of walking while using a mobile phone on balance perturbation and joint movement among young adults.

METHODS

Sixteen healthy college students with no history of brain injury were tested. The participants were asked to walk under four different conditions: (1) walking, (2) browsing, (3) dialing, and (4) texting. Indicators related to balance control and lower limb kinematic/kinetic parameters were analyzed using the continuous relative phase and statistical nonparametric mapping methods.

RESULTS

Walking while using a mobile phone slowed participants' gait speed and reduced the cadence, stride length, and step length. The posterior tilt angle (0-14%, 57-99%), torque of the hip flexion (0-15%, 30-35%, 75-100%), and angle of the hip flexion (0-28%, 44-100%) decreased significantly. The activation of biceps femoris and gastrocnemius, hip stiffness, and ankle stiffness increased significantly. This impact on gait significantly differed among three dual tasks: texting > browsing > dialing.

CONCLUSION

Che overlap of walking and mobile phone use affects the gait significantly. The "hip-ankle strategy" may result in a "smooth" but slower gait, while this strategy was deliberate and tense. In addition, this adjustment also increases the stiffness of the hip and ankle, increasing the risk of fatigue. Findings regarding this effect may prove that even for young healthy adults, walking with mobile phone use induces measurable adjustment of the motor pattern. These results suggest the importance of simplifying the control of the movement.

Technology-Assisted Cognitive Motor Dual-Task Rehabilitation in Chronic Age-Related Conditions: Systematic Review

BACKGROUND

Cognitive-motor dual-task (CMDT) is defined as the parallel processing of motor (eg, gait) and cognitive (eg, executive functions) activities and is an essential ability in daily life. Older adults living with frailty, chronic conditions (eg, neurodegenerative diseases), or multimorbidity pay high costs during CMDT. This can have serious consequences on the health and safety of older adults with chronic age-related conditions. However, CMDT rehabilitation can provide useful and effective therapies for these patients, particularly if delivered through technological devices.

OBJECTIVE

This review aims to describe the current technological applications, CMDT rehabilitative procedures, target populations, condition assessment, and efficacy and effectiveness of technology-assisted CMDT rehabilitation in chronic age-related conditions.

METHODS

We performed this systematic review, following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, on 3 databases (Web of Science, Embase, and PubMed). Original articles that were published in English; involved older adults (>65 years) with ≥1 chronic condition and/or frailty; and tested, with a clinical trial, a technology-assisted CMDT rehabilitation against a control condition were included. Risk of bias (Cochrane tool) and the RITES (Rating of Included Trials on the Efficacy-Effectiveness Spectrum) tool were used to evaluate the included studies.

RESULTS

A total of 1097 papers were screened, and 8 (0.73%) studies met the predefined inclusion criteria for this review. The target conditions for technology-assisted CMDT rehabilitation included Parkinson disease and dementia. However, little information regarding multimorbidity, chronicity, or frailty status is available. The primary outcomes included falls, balance, gait parameters, dual-task performance, and executive functions and attention. CMDT technology mainly consists of a motion-tracking system combined with virtual reality. CMDT rehabilitation involves different types of tasks (eg, obstacle negotiation and CMDT exercises). Compared with control conditions, CMDT training was found to be pleasant, safe, and effective particularly for dual-task performances, falls, gait, and cognition, and the effects were maintained at midterm follow-up.

CONCLUSIONS

Despite further research being mandatory, technology-assisted CMDT rehabilitation is a promising method to enhance motor-cognitive functions in older adults with chronic conditions.

Cognitive challenge as a probe to expose sex- and age-related differences during static contractions

Despite activities of daily living being frequently performed simultaneously with a cognitive task, motor function is often investigated in isolation, which can hinder the applicability of findings. This brief review presents evidence that 1) performing a cognitive challenge simultaneously with a motor task can negatively impact force steadiness and fatigability of limb muscles during a static contraction, 2) the negative impact on old adults (>65 years old), particularly older women is greater than young when a cognitive challenge is simultaneously performed with a static motor task, 3) age-related mechanisms potentially explain impairments in motor performance in the presence of a cognitive challenge, and 4) the mechanisms for the age-related decrements in motor performance can be distinct between men and women. These observations are highly relevant to the older adults, given the increased risk of accidents and injury when a motor task is performed with a high cognitive-demand task, especially in light of the expanding reliance on an aging workforce.

Test-retest reliability of kinematic and kinetic parameters during dual-task stair walking in the elderly

Objective: This study aims to evaluate the test-retest reliability of kinematics and kinetics during single and dual-task stair walking in the elderly. Methods: Fifteen healthy elderly adults were recruited. Kinematic and kinetic parameters were measured using an infrared motion analysis system (Vicon, Oxford Metrics Ltd., Oxford, United Kingdom) and force platforms (Switzerland, Kistler 9287BA and 9281CA). Participants were tested under single-task and dual-task (serial 3 subtractions or carrying a cup of water) conditions. Each participant completed two sessions on two separate days with a 1-week interval. Intraclass correlation coefficients (ICC), Pearson correlation coefficient (r), and Bland-Altman plot were used to assess the reliability of stair walking. Results: When ascending stairs, the ICC of kinematics and kinetics ranged from fair to excellent (ICC = 0.500-0.979) in the single and dual tasks, except for step length (ICC = 0.394) in the single task. The r value of kinematics and kinetics ranged from 0.704 to 0.999. When descending stairs, the ICC of kinematics and kinetics ranged from good to excellent (ICC = 0.661-0.963), except for min hip moment (ICC = 0.133) and min ankle moment (ICC = 0.057) in the manual task. The r value of kinematics and kinetics ranged from 0.773 to 0.960 in the single and dual tasks. In the Bland-Altman plots, all the zero values and most of the dots fell in the 95% confidence interval, and the mean difference was found to be close to zero for all the parameters during stair walking. Conclusion: These results obtained from this study show the good test-retest reliability of step cadence, step speed, and step width during single- and dual-task stair walking in the elderly, and the poor reliability of step length during ascending stairs. All the kinetic parameters, including min hip moment, max knee moment, and min ankle moment, had good test-retest reliability during single- and dual-task stair walking, but min hip moment and min ankle moment had poor reliability during manual-task descending stair. These results may help researchers in the assessment of biomechanics of dual-task stair walking in the elderly and to interpret the effect of interventions in this population.

Effectiveness of a Cognitive-Motor Training Program in Reducing Attentional Cost During Walking in Patients With Multiple Sclerosis

The purpose of this study was to assess the efficacy of a combined training program (CTP) in reducing the effects of dual tasking on the temporal parameters and kinematics of gait, as compared with single-task gait. A controlled, randomized, intervention study was performed in an intervention group and a control group. The intervention group attended three weekly CTP sessions for 24 weeks. Gait pattern was evaluated prior to the baseline intervention, at 12 weeks, and at 24 weeks (Repost). The sample was composed of 22 subjects diagnosed with multiple sclerosis with an Expanded Disability Status Scale score of 0-5.5. A total of 12 patients were allocated to the intervention group and another 10 to the control group. A three-dimensional photogrammetry scanner was connected to a selective attention system designed to present a dual-task gait condition. Dual tasking had an impact on all spatiotemporal parameters of gait, and the most remarkable effect of dual tasking was on double-support time, which increased by 9% with respect to normal walking. In contrast, dual tasking had a trivial effect on single-support time. The CTP was effective in reducing the effects of dual tasking on stride length and velocity of the center of mass after Repost of training (p < .05). The CTP reduced time in double-support phase, whereas single-support time increased after Repost of intervention. The application of the CTP had no effect on the cost of the double task after 12 weeks of intervention. It is suggested to increase the application time over Repost.

A Pilot Study of the Effects of Individualized Home Dual Task Training by Mobile Health Technology in People with Dementia

The objective of this pilot study was to evaluate the effects of dual-task training implemented by mobile health technology on performance on motor and dual-task tests in subjects with dementia. Nineteen subjects with a medical diagnosis of dementia were assigned to an experimental group (EG, n = 12) or control group (CG, n = 7). The EG participated in 24 sessions (3/week) of a homebase dual-task exercises program, in addition to their ongoing cognitive and physiotherapy treatment. The training program was implemented individually in the patient's home by caregivers or relatives through electronic devices controlled by a mobile application. Before (Pre) and after (Post) the program, performance on motor and motor/cognitive (dual-task) tests were evaluated. Motor evaluation included gait at preferred and maximal speed, the Up and Go, and the Handgrip Strength test. Dual-task tests included gait with subtraction 3 s from 100 and naming animals (verbal fluency). The CG only performed the evaluations in addition to their cognitive and physiotherapy treatment. The statistical analysis (ANOVA Group*Test) showed a statically significant improvement for both dual-task tests in the EG after the training program, while the CG showed an impairment in the verbal fluency test. Conclusion: the implementation of a home exercise program carried out with mobile technology in people with dementia is feasible and positively affects their performance on dual tasks.

The Implementation of a Return-to-Play Protocol with Standardized Physical Therapy Referrals in a Collegiate Football Program: PT's Role in Return-to-Play, A Clinical Commentary

Sport-related concussions (SRCs) are multi-faceted injuries requiring coordinated care for return-to-play (RTP). Although the number of concussions in collegiate football is increasing annually, there is poor standardization among RTP protocols. Recent evidence suggests there is an increased risk of lower extremity injury, neuropsychiatric consequences, and re-injury after SRC, and risk factors for a prolonged recovery from SRC have also been identified. Evidence demonstrates a faster RTP and improved outcomes with early physical therapy intervention; however, this is not yet common practice in the treatment of acute SRC. There is little guidance available on the development and implementation of a multidisciplinary RTP rehabilitation protocol for SRC that incorporates standardized physical therapy. By describing an evidence-based RTP protocol with standardized physical therapy management, and measures taken to implement this protocol, this clinical commentary aims to identify steps in treating SRC that can be used to improve recovery. The purpose of this commentary is to: a) survey the current state of standardization of RTP protocols in collegiate football; b) highlight the development and implementation of a RTP protocol with standardized physical therapy referral and management in an NCAA Division II collegiate football program; and c) describe results of a full-season pilot study, including time to evaluation, time to RTP, rate of re-injury or lower extremity injury, and the clinical significance of protocol implementation.

Level of Evidence

Level V.

Spatiotemporal Parameters of Gait Among Adolescent Athletes with Concussion When Performing a Visuospatial Cognitive Task

Background

Adolescent athletes aged 10 to 19 years are at the highest risk of experiencing sport-related concussions (SRCs). Despite the known deficits and battery of assessments following concussion, postural stability during dual-task gait remains understudied in this population.

Purpose

The purpose of this study was to evaluate the dual-task cost (DTC) in adolescents with an acute or chronic SRC compared to reference values from healthy athlete peers for spatiotemporal parameters of gait during walking with and without a concurrent visuospatial memory task presented on a hand-held tablet. Researchers hypothesized that adolescents during the acute phase of concussion would be likely to experience a greater DTC compared to healthy peers in at least one spatiotemporal parameter of gait when walking within the dual-task paradigm.

Study Design

Cross-sectional, observational cohort design.

Methods

Adolescents with concussion were recruited to participate. Subjects were divided into acute and chronic categories based on significant differences in the neuropsychological function after a period of 28 days. They walked at a self-selected speed along the 5.186-meter GAITRite® Walkway System with and without a concurrent visuospatial cognitive task presented on a hand-held tablet. Outcomes included normalized velocity (m/s), step length (m), and double limb (DLS) and single limb support (SLS) (defined as the percent of a gait cycle [%GC]). The data were then compared to the previously published reference values established using the same methods in the healthy athlete participants for all spatiotemporal parameters of gait.

Results

Data was collected on 29 adolescent athletes with SRC. Among males (15.53+/-1.12 years) with SRC, 20% of acute and 10% of chronic cases experienced a greater DTC compared to healthy athlete reference values. A similarly increased DTC was experienced by 83% of acute and 29% of chronic SRC cases for females (15.58+/-1.16 years).

Conclusions

Adolescent athletes with concussion may continue demonstrating deficits in gait capabilities even in the chronic phase, and compensatory gait strategies were not the same between males and females. Dual-task cost assessment using the GAITRite® may be a valuable adjunct to comprehensive analysis of gait following SRC.

Level of Evidence

2.

Disentangling working memory from multiple-object tracking: Evidence from dual-task interferences

Multiple object tracking (MOT) is generally regarded as a pure attention-consuming task that draws heavily on attention resources. In the present study, we adopted a cross-channel visual-audio dual-task paradigm, i.e., the MOT task combined with the concurrent auditory N-back working memory task, to test whether working memory indeed plays a necessary role in the process of multiple tracking, as well as to further identify the specific types of working memory components involved in this process. Experiments 1a and 1b examined the relationship between the MOT task and nonspatial object working memory (OWM) processing by manipulating the tracking load and working memory load, respectively. Results in both experiments indicated that the concurrent nonspatial OWM task did not have a significant effect on the tracking capacity of the MOT task. In contrast, Experiments 2a and 2b examined the relationship between the MOT task and spatial working memory (SWM) processing by a similar approach. Results in both experiments indicated that the concurrent SWM task significantly impaired the tracking capacity of the MOT task, showing a gradual decrease with increasing SWM load. Overall, our study provides empirical evidence that multiple object tracking does involve working memory, primarily related to spatial working memory rather than nonspatial object working memory, which sheds more light on the mechanisms of multiple object tracking.

Investigation of the dual-task performance and affecting factors in female patients with fibromyalgia syndrome

Recent studies report that dual-task (DT) performance might be affected in patients with fibromyalgia syndrome (FMS). This cross-sectional study aims to compare the DT performance in female patients with FMS and healthy controls, and to investigate the DT-related factors in these patients. This study was conducted at a university hospital between November 2021 and April 2022. Forty females aged 30-65, diagnosed with FMS, and 40 aged-matched pain-free healthy controls were included. All participants performed the Timed Up and Go Test under a single task (ST) and a cognitive DT condition, and the DT cost was calculated. The following evaluations were applied; The six-minute walk test, Baecke Habitual Physical Activity Questionnaire, Multidimensional Fatigue Inventory-20, Toronto Alexithymia Scale, Trail Making Test, and the Revised Fibromyalgia Impact Questionnaire. As a result of the study, the patient group showed lower performance than controls in both, ST and DT conditions (p < .05). Disease duration, pain and fatigue severity, functional capacity, leisure time and physical activity total scores, alexithymia scores, health status, and cognitive variables were correlated with DT performance in the patient group (p < .05). According to our results, we consider that the rehabilitation approach for females with FMS should take into account DT and related characteristics.

A dual-task gait test detects mild cognitive impairment with a specificity of 91.2

Background

Mild cognitive impairment (MCI) is a valuable intervention window in the progress of senile dementia, but the question of how to easily and conveniently detect MCI in the community remains unanswered. Gait performance reflects cognitive function, but how to reliably detect MCI through gait testing is still being explored.

Objective

To develop a dual-task gait testing method that could reliably detect MCI in the community.

Methods

A cross-sectional diagnostic study was conducted in 111 older adults (mean age = 72.14 ± 6.90 years) from five communities in Wuhan, China. A novel dual-task gait testing method, walking while identifying animals in pictures (AniP-DT gait test), was developed. The participants were classified into MCI or cognitively intact based on their performance on the Montreal Cognitive Assessment Scale (MoCA). Gait performance was assessed using both single-task and the AniP-DT gait test. Multiple linear regression and binary logistic regression were used to model the association between gait speed and cognitive status, and receiver operating characteristic (ROC) curve analysis was used to assess the discrimination ability.

Results

Compared to the cognitively intact group, the gait speed of the MCI group was lower in both single-task and the AniP-DT gait tests. The gait speed of the AniP-DT gait test was significantly associated with MoCA scores after adjusting the covariates and exhibited good discrimination ability in MCI detection (AUC = 0.814), with a specificity of 91.2%. ROC analysis of the logistic models revealed better discrimination ability of dual-task gait velocity when adjusted with age and years of education (AUC = 0.862).

Conclusion

The evidence in this study suggested that the AniP-DT gait test could be an easy and reliable screening tool for MCI in community older adults.

Measured and Perceived Exercise Intensity During the Performance of Single-Task, Cognitive-Motor Dual-Task, and Exergame Training: Transversal Study

BACKGROUND

The physical and cognitive loads borne during exergaming may differ from more conventional cognitive-motor dual-task trainings.

OBJECTIVE

The aim of this pilot transversal study was to compare objectively measured and perceived exercise intensity during exergame, cognitive-motor dual-task, and single-task training sessions.

METHODS

We recruited apparently healthy young adults who carried out one session of each type of training: exergaming, cognitive-motor dual-tasking, and single-tasking. We used a custom-made exergame as support. The sessions lasted 30 minutes, were spaced at least 24 hours apart, and took place in random order for each group of 4 participants. We used heart rates to assess exercise intensity and the modified Borg scale to assess perception of intensity. In all, 16 apparently healthy young participants carried out all sessions.

RESULTS

There was no difference between the different types of training in mean heart rates (P=.27), peak heart rates (P=.50), or Borg scale scores (P=.40). Our custom-made exergame's objectively measured and perceived physical load did not differ between cognitive-motor dual-task and single-task training.

CONCLUSIONS

As a result, our exergame can be considered to be as challenging as more traditional physical training. Future studies should be conducted in older adults with or without cognitive impairments and incorporate an assessment of cognitive performance.

Abnormal gait and motor cortical processing in drug-resistant juvenile myoclonic epilepsy

BACKGROUND

Juvenile myoclonic epilepsy (JME) is characterized by generalized seizures. Nearly 30% of JME patients are drug-resistant (DR-JME), indicating a widespread cortical dysfunction. Walking is an important function that necessitates orchestrated coordination of frontocentral cortical regions. However, gait alterations in JME have been scarcely investigated. Our aim was to assess changes in gait and motor-evoked responses in DR-JME patients.

METHODS

Twenty-nine subjects (11 JME drug-responder, 8 DR-JME, and 10 healthy controls) underwent a gait analyses during usual walking and dual-task walking. Later, subjects underwent 64-channel EEG recordings while performing a simple motor task. We calculated the motor-evoked current source densities (CSD) at a priori chosen cortical regions. Gait and CSD measures were compared between groups and tasks using mixed model analysis.

RESULTS

DR-JME patients demonstrated an altered gait pattern that included slower gait speed (p = .018), reduced cadence (p = .003), and smaller arm-swing amplitude (p = .011). The DR-JME group showed higher motor-evoked CSD in the postcentral gyri compared to responders (p = .049) and both JME groups showed higher CSD in the superior frontal gyri compared to healthy controls (p < .011). Moreover, higher CSD in the superior frontal gyri correlated with worse performance in dual-task walking (r > |-0.494|, p < .008).

CONCLUSIONS

These alterations in gait and motor-evoked responses in DRE-JME patients reflect a more severe dysfunction of motor-cognitive neural processing in frontocentral regions, leading to poorer gait performance. Further studies are needed to investigate the predictive value of altered gait and cortical motor processing as biomarkers for poor response to treatment in JME and other epilepsy syndromes.

Postural Control of Patients with Low Back Pain Under Dual-Task Conditions

Low back pain is a major global public health problem, but the current intervention effect is not ideal. A large body of previous literature suggests that patients with chronic low back pain may have abnormal postural control, which is more evident in the dual task situation. In recent years, research on postural control in patients with low back pain under dual-task conditions has gradually become a hot topic. However, the results obtained from these studies were not entirely consistent. In this review, we summarized relevant studies on the performance of postural control in patients with low back pain under dual-task conditions, analyze it from the perspective of the theoretical model of dual-task interaction, the specific research paradigm of dual task, the performance of postural control, and the related factors affecting postural control performance, etc. It was reasonable to assume that patients with low back pain might have a certain degree of abnormal postural control, and this abnormality was affected by comprehensive factors such as age, cognitive resource capacity, attention needs, complex sensorimotor integration, external environment, etc. Furthermore, postural control performance in low back pain patients under dual-task conditions was further influenced by the nature and complexity of the different tasks. In general, the more attention resources were needed, the external environmental conditions were worse, and the age-related functions were degenerate, etc., the weaker posture control ability was. In short, a deeper understanding of postural control in patients with low back pain under dual-task conditions may shed light on more references for the rehabilitation and management of low back pain, as well as some new ideas for scientific research on cognition and postural control.

The role of alerting in the attentional boost effect

Stimuli presented simultaneously with behaviorally relevant events (e.g., targets) are better memorized, an unusual effect defined as the attentional boost effect (ABE). We hypothesized that all types of behaviorally relevant events, including attentional cues, can promote the encoding process for the stimuli paired with them, and the attentional alerting network can amplify the ABE. The two experiments we conducted demonstrated that not all behaviorally relevant events, including alerting cues, benefit the processing of concurrently paired stimuli. We also found that the presence of a cue prior to a target can extend the memory advantage produced by target detection, but this advantage can only be observed within a limited range of time. Overall, our study provides the first evidence that the alerting network plays an important role in the ABE.

Assessing upper extremity-cognitive dual-task ability in neurological populations: A systematic review

BACKGROUND

Dual-task involves performing cognitive and motor tasks together, which requires executive functions that may be impaired in individuals with neurological conditions. Therefore, it is important to accurately assess executive functions to plan a therapeutic intervention.

OBJECTIVE

To characterize the use of upper extremity-cognitive dual-task assessment and to describe variables correlated with dual-task ability.

METHODS

An electronic search of databases (MEDLINE, EMBASE, CINAHL, and PsycINFO) was carried out using a combination of the following terms: upper-extremity, dual/concurrent task, and cognitive/motor tasks. Two reviewers independently completed data extraction and assessed study quality.

RESULTS

1,946 studies were identified; 25 studies met the inclusion criteria. The purpose of using an upper extremity-cognitive dual-task assessment varied between studies as well as the upper extremity motor tasks used: pegboard (N = 14), arm curl (N = 9), finger-tapping (N = 3), and reaching (N = 1) tests. Dual-task ability was reported as the motor-cognitive interference (N = 15) and as motor cost (N = 12). Dual-task ability was correlated to cognition, brain activity, and daily function, and was significantly different between healthy and neurological individuals.

CONCLUSION

Upper extremity cognitive dual-task paradigm is gaining popularity in clinical research, but lacks standardized tools, testing procedures, and calculations. A structured assessment procedure is needed for clinical use and future research.

Effects of noninvasive brain stimulation on dual-task performance in different populations: A systematic review

Background

Increasing research has investigated the use of noninvasive brain stimulation (NIBS) on augmenting dual-task (DT) performance.

Objective

To investigate the effects of NIBS on DT performance in different populations.

Methods

Extensive electronic database search (from inception to November 20, 2022) was conducted in PubMed, Medline, Cochrane Library, Web of Science and CINAHL to identify randomized controlled trials (RCTs) that investigated the effects of NIBS on DT performance. Main outcomes were balance/mobility and cognitive function under both single-task (ST) and DT conditions.

Results

Fifteen RCTs were included, involving two types of intervention techniques: transcranial direct current stimulation (tDCS) (twelve RCTs) and repetitive transcranial magnetic stimulation (rTMS) (three RCTs); and four different population groups: healthy young adults, older adults, Parkinson's disease (PD), and stroke. For tDCS, under DT condition, significant improvement in speed was only observed in one PD and one stroke RCT, and stride time variability in one older adults RCT. Reduction in DTC in some gait parameters was demonstrated in one RCT. Only one RCT showed significant reduction in postural sway speed and area during standing under DT condition in young adults. For rTMS, significant improvements in fastest walking speed and time taken to Timed-up-and-go test under both ST and DT conditions were observed at follow-up in one PD RCT only. No significant effect on cognitive function in any RCT was observed.

Conclusion

Both tDCS and rTMS showed promising effects in improving DT walking and balance performance in different populations, however, due to the large heterogeneity of included studies and insufficient data, any firm conclusion cannot be drawn at present.

Using Cognitive-Motor Dual-Tasks and Functional Near-Infrared Spectroscopy to Characterize Older Adults with and without Subjective Cognitive Decline

BACKGROUND

Subjective cognitive decline (SCD) refers to individuals who report persistent cognitive deficits but perform normally on neuropsychological tests. Performance may be facilitated by increased prefrontal cortex activation, known as neural compensation, and could be used to differentiate between older adults with and without SCD.

OBJECTIVE

This cross-sectional pilot study measured changes in the hemodynamic response (ΔHbO2) using functional near-infrared spectroscopy (fNIRS) as well as cognitive and motor performance during fine and gross motor dual-tasks in older adults with and without SCD.

METHODS

Twenty older adults over 60 years old with (n = 10) and without (n = 10) SCD were recruited. Two experiments were conducted using 1) gross motor walking and 2) fine motor finger tapping tasks that were paired with an n-back working memory task. Participants also completed neuropsychological assessments and questionnaires on everyday functioning.

RESULTS

Repeated measures ANOVAs demonstrated slower response times during dual-task gait compared to the single task (p = 0.032) and in the non-SCD group, slower gait speed was also observed in the dual compared to single task (p = 0.044). Response times during dual-task finger tapping were slower than the single task (p = 0.049) and greater ΔHbO2 was observed overall in the SCD compared to non-SCD group (p = 0.002).

CONCLUSIONS

Examining neural and performance outcomes revealed differences between SCD and non-SCD groups and single and dual-tasks. Greater brain activation during dual-task finger tapping may reflect neural compensation, which should be examined in a larger sample and longitudinally to better characterize SCD.

A dual-task-embedded virtual reality system for intelligent quantitative assessment of cognitive processing speed

Introduction

Processing speed is defined as the ability to quickly process information, which is generally considered as one of the affected cognitive functions of multiple sclerosis and schizophrenia. Paper-pencil type tests are traditionally used in the assessment of processing speed. However, these tests generally need to be conducted under the guidance of clinicians in a specific environment, which limits their application in cognitive assessment or training in daily life. Therefore, this paper proposed an intelligent evaluation method of processing speed to assist clinicians in diagnosis.

Methods

We created an immersive virtual street embedded with Stroop task (VR-Street). The behavior and performance information was obtained by performing the dual-task of street-crossing and Stroop, and a 50-participant dataset was established with the label of standard scale. Utilizing Pearson correlation coefficient to find the relationship between the dual-task features and the cognitive test results, and an intelligent evaluation model was developed using machine learning.

Results

Statistical analysis showed that all Stroop task features were correlated with cognitive test results, and some behavior features also showed correlation. The estimated results showed that the proposed method can estimate the processing speed score with an adequate accuracy (mean absolute error of 0.800, relative accuracy of 0.916 and correlation coefficient of 0.804). The combination of Stroop features and behavior features showed better performance than single task features.

Discussion

The results of this work indicates that the dual-task design in this study better mobilizes participants' attention and cognitive resources, and more fully reflects participants' cognitive processing speed. The proposed method provides a new opportunity for accurate quantitative evaluation of cognitive function through virtual reality.

Prioritizing limb loading improves symmetry during dual-tasking in individuals following anterior cruciate ligament reconstruction

Understanding the extent to which attention prioritization interfere with limb loading in daily activities following anterior cruciate ligament reconstruction (ACLr) is important for reshaping loading behaviors. A dual-task paradigm, prioritizing limb loading symmetry (LLS) during standing or response time during an upper extremity task response time task was used to probe the effects of attention prioritization of loading. Individuals 115.6 ± 17.8 days post-ACLr (ACLr; n = 13) and matched healthy individuals (n = 13; CTRL) performed a simple response time (RT) task and 2 dual tasks prioritizing limb loading (LS-RT) and response time (RT-LS). 2 × 3 General Linear Model repeated measures analyses determined effects of group and focus condition on LLS error and response time. Significant interaction (P = 0.010) was noted in LLS error. ACLr group, exhibited greater LLS error in RT (P = 0.001) and RT-LS (P = 0.001) than LS-RT condition. ACLr group exhibited greater LLS error in the RT (P = 0.001) and RT-LS (P = 0.040) than CTRL, but not in LS-RT. A main effect of condition (P < 0.001) for response time indicated that times were slower in LS-RT compared to RT (P < 0.001) and to RT-LS (P < 0.001) for both groups. These data suggest that limb loading symmetry during standing is more automatic for controls than individuals following ACLr. Unlike controls, improving loading symmetry during standing requires additional attention in individuals in early recovery following ACLr.

Cognitive rehabilitation in multiple sclerosis: Three digital ingredients to address current and future priorities

Multiple sclerosis (MS) is a neurological chronic disease with autoimmune demyelinating lesions and one of the most common disability causes in young adults. People with MS (PwMS) experience cognitive impairments (CIs) and clinical evidence shows their presence during all MS stages even in the absence of other symptoms. Cognitive rehabilitation (CR) aims at reducing CI and improving PwMS' awareness of cognitive difficulties faced in their daily living. More defined cognitive profiles, easier treatment access and the need to transfer intervention effects into everyday life activities are aims of utmost relevance for CR in MS. Currently, advanced technologies may pave the way to rethink CR in MS to address the priority of more personalized and effective, accessible and ecological interventions. For this purpose, digital twins, tele-cognitive-rehabilitation and metaverse are the main candidate digital ingredients. Based on scientific evidences, we propose digital twin technology to enhance MS cognitive phenotyping; tele-cognitive-rehabilitation to make feasible the cognitive intervention access to a larger number of PwMS; and metaverse to represent the best choice to train real-world dual- and multi-tasking deficits in virtual daily life environments. Moreover, multi-domain high-frequency big-data collected through tele-cognitive-assessment, tele-cognitive-rehabilitation, and metaverse may be merged to refine artificial intelligence algorithms and obtain increasingly detailed patient's cognitive profile in order to enhance intervention personalization. Here, we present how these digital ingredients and their integration could be crucial to address the current and future needs of CR facilitating the early detection of subtle CI and the delivery of increasingly effective treatments.

Effects of Single-Task, Dual-Task and Analogy Training during Gait Rehabilitation of Older Adults at Risk of Falling: A Randomized Controlled Trial

It has been suggested that implicit motor learning via dual-task or analogy training during gait rehabilitation may yield better outcomes in older adults by reducing the propensity for the conscious processing of movements (movement-specific reinvestment). The current study investigated the immediate effects of single-task, dual-task, and analogy training on reinvestment propensity and fall-related rehabilitation outcomes among older adults at risk of falling. Seventy-one older adults were randomly allocated to the single-task (ST), dual-task (DT), or analogy (AG) training conditions and received 12 training sessions. We assessed the reinvestment propensity, functional gait and balance, functional mobility, balance ability, single-task and dual-task walking abilities, and fear of falling at baseline (before training) and immediately after training. Our findings revealed a lack of training effect on reinvestment propensity for all groups. However, all groups displayed significant improvements in functional gait and balance (p < 0.001), functional mobility (p = 0.02), and balance ability (p = 0.01) after training. AG appeared to be superior to DT and ST, as it was the only condition that resulted in significant improvements in both single-task and dual-task walking abilities (p < 0.001). Implementing movement analogies could be a feasible and useful gait rehabilitation strategy for fall prevention and wellbeing promotion among older adults.

Factors Associated with Dual-Fluency Walk Speed Improvement after Rehabilitation in Older Patients

Walk speed measured under dual-task conditions (neurocognitive tasks) could reflect patient performance in real-life. Rehabilitation programs are effective in increasing walk speed, but few studies have evaluated the associations between geriatric factors and rehabilitation efficacy under dual-task conditions. Our objective was to investigate the association between geriatric factors and an increase in dual-task walk speed (threshold of 0.1 m/s), after a multidisciplinary rehabilitation program. We performed a retrospective cohort study that included patients aged 75 years and over, who underwent a complete rehabilitation program and who had a neurocognitive assessment at baseline. The primary outcome was the increase in the dual-task (fluency verbal task) walking speed between pre- and post-rehabilitation assessments. In this study, 145 patients were included, with a mean age of 83.6 years old. After rehabilitation, dual-task walk speed increase in 62 (43%) patients. In multivariate analysis, the following factors were associated with an increase in dual-task walk speed: IADL (OR 2.50, 95% CI [1.26; 4.94], p = 0.009), vitamin D level (OR 0.83, 95% CI [0.72; 0.95], p = 0.008), severe sarcopenia (OR 0.00, 95% CI [0.00; 0.32], p = 0.016), depression (OR 15.85, 95% CI [1.32; 190.40], p = 0.029), number of drugs (OR 1.41, 95% CI [1.04; 1.92], p = 0.027), initial dual-fluency walk speed (OR 0.92, 95% CI [0.86; 0.98], p = 0.014) and time interval between initial and final assessments (OR 0.98, 95% CI [0.96; 1.00], p = 0.06). Identifying patients that are less resilient to rehabilitation may promote a centered-patient approach for an individualized and optimized rehabilitation care.

Effects of a forced cycling program with cognitive stimulation on symptomatology, physical condition, and cognition in people diagnosed with Parkinson disease

BACKGROUND AND OBJECTIVES

Parkinson disease may present difficulties in performing dual tasks. The use of dual tasks during training can improve different abilities. Therefore, the objective of this study is creating a protocol, based on standard protocol items recommendations for interventional trials compliant, for a clinical trial study conduct, review, reporting, and interpretation. This protocol will provide the framework and a guide to a randomized double-blind study, that will be conducted to assess the influence of a cycling exercise program combined with a cognitive task, on cognitive and physical Parkinson disease aspects.

METHODS

Designed a protocol for a double-blind randomized study, where participants will perform a dual tasks intervention with cycling and a cognitive task. The revised version of the unified Parkinson disease rating scale, the Parkinson disease questionnaire, the timed up and go Test, the 30 seconds chair sit to stand test, the Stroop and the trail making test will be used to measure outcomes.

DISCUSSION

Research in Parkinson disease suggests that an improvement of motor and cognitive functions of Parkinson disease patients can be achieved by modifying different motor and cognitive pathways. The results of the present study will yield findings on both the physical and cognitive response to an intervention that combines a cognitive task with a motor task in Parkinson disease patients and will be essential tool for a better conducting of the clinical trial study.

Motor Cognitive Dual-Task Testing to Predict Future Falls in Multiple Sclerosis: A Systematic Review

BACKGROUND

Mobility and cognitive impairments are often associated with increased fall risk among people with multiple sclerosis (PwMS). However, evidence on the concurrent assessment of gait or balance and cognitive tasks (dual-task) to predict falls appears to be inconsistent.

OBJECTIVE

To summarize the ability of gait or balance dual-task testing to predict future falls among PwMS.

METHODS

Seven databases including PubMed, Embase, Web of Science, Scopus, CINHAL, SPORTDiscuss, and PsycINFO were searched from inception to May 2022. Two independent reviewers identified studies that performed a dual-task testing among adults with multiple sclerosis and monitored falls prospectively for at least 3 months. Both reviewers also evaluated the quality assessment of the included studies.

RESULTS

Eight studies with 484 participants were included in the review. Most studies (75%) indicated that dual-task testing and dual-task cost did not discriminate prospective fallers (⩾1 fall) and non-fallers (0 fall) and were not found as predictors of future falls. However, dual-task cost of walking velocity (OR = 1.23, 95% CI 0.98-4.45, P = .05) and dual-task of correct response rate of serial 7 subtraction (OR = 1.34, 95% CI 1.04-3.74, P = .02) were significantly associated with increased risk of recurrent falls (≥2 falls). Pattern of cognitive-motor interference was also associated with an increased risk of falling. All studies presented with strong quality.

CONCLUSION

The scarce evidence indicates that dual-task testing is not able to predict future falls among PwMS. Further research with more complex motor and cognitive tasks and longer-term fall monitoring is required before dual-task testing can be recommended as a predictor of future falls in this population.

Tai Chi practice enables prefrontal cortex bilateral activation and gait performance prioritization during dual-task negotiating obstacle in older adults

BACKGROUND

With aging, the cognitive function of the prefrontal cortex (PFC) declined, postural control weakened, and fall risk increased. As a mind-body exercise, regular Tai Chi practice could improve postural control and effectively prevent falls; however, underlying brain mechanisms remained unclear, which were shed light on by analyzing the effect of Tai Chi on the PFC in older adults by means of functional near-infrared spectroscopy (fNIRS).

METHODS

36 healthy older adults without Tai Chi experience were divided randomly into Tai Chi group and Control group. The experiment was conducted four times per week for 16 weeks; 27 participants remained and completed the experiment. Negotiating obstacle task (NOT) and negotiating obstacle with cognitive task (NOCT) were performed pre- and post-intervention, and Brodmann area 10 (BA10) was detected using fNIRS for hemodynamic response. A three-dimensional motion capture system measured walking speed.

RESULTS

After intervention in the Tai Chi group under NOCT, the HbO2 concentration change value (ΔHbO2) in BA10 was significantly greater (right BA10: p = 0.002, left BA10: p = 0.001), walking speed was significantly faster (p = 0.040), and dual-task cost was significantly lower than pre-intervention (p = 0.047). ΔHbO2 in BA10 under NOCT was negatively correlated with dual-task cost (right BA10: r = -0.443, p = 0.021, left BA10: r = -0.448, p = 0.019). There were strong negative correlations between ΔHbO2 and ΔHbR under NOCT either pre-intervention (left PFC r = -0.841, p < 0.001; right PFC r = -0.795, p < 0.001) or post-intervention (left PFC r = -0.842, p < 0.001; right PFC r = -0.744, p < 0.001).

CONCLUSION

Tai Chi practice might increase the cognitive resources in older adults through the PFC bilateral activation to prioritize gait performance during negotiating obstacles under a dual-task condition.

Patient-Reported Outcome Measures for Assessing Dual-Task Performance in Daily Life: A Review of Current Instruments, Use, and Measurement Properties

The patient perspective of dual-task (DT) impairment in real life is unclear. This review aimed (i) to identify patient-reported outcome measures (PROMs) on DT and evaluate their measurement properties and (ii) to investigate the usage of PROMs for the evaluation of DT difficulties. A systematic literature search was conducted using PubMed and Web of Science from inception to March 2022. Methodological quality was evaluated using the COSMIN checklist. Six studies examined the measurement properties of DT PROMs. Nine studies used DT PROMs as the outcome measure. Five PROMs were identified, including the Divided Attention Questionnaire (DAQ), Dual-Task-Impact on Daily-life Activities Questionnaire (DIDA-Q), a Questionnaire by Cock et al. (QOC), Dual-Tasking Questionnaire (DTQ), and Dual-Task Screening-List (DTSL). Fourteen measurement properties were documented: five (35.7%) rated quality as "sufficient", six (42.8%) "insufficient", and three (21.4%) "indeterminate". The quality of evidence for each measurement property ranged from very low to high. While DT performance is investigated in many populations, the use of PROMs is still limited, although five instruments are available. Currently, due to insufficient data, it is not possible to recommend a specific DT PROM in a specific population. An exception is DIDA-Q, which has the highest quality of measurement properties in people with multiple sclerosis.

Digitizing a Therapeutic: Development of an Augmented Reality Dual-Task Training Platform for Parkinson's Disease

Augmented reality (AR) may be a useful tool for the delivery of dual-task training. This manuscript details the development of the Dual-task Augmented Reality Treatment (DART) platform for individuals with Parkinson's disease (PD) and reports initial feasibility, usability, and efficacy of the DART platform in provoking dual-task interference in individuals with PD. The DART platform utilizes the head-mounted Microsoft HoloLens2 AR device to deliver concurrent motor and cognitive tasks. Biomechanical metrics of gait and cognitive responses are automatically computed and provided to the supervising clinician. To assess feasibility, individuals with PD (N = 48) completed a bout of single-task and dual-task walking using the DART platform. Usability was assessed by the System Usability Scale (SUS). Dual-task interference was assessed by comparing single-task walking and walking during an obstacle course while performing a cognitive task. Average gait velocity decreased from 1.06 to 0.82 m/s from single- to dual-task conditions. Mean SUS scores were 81.3 (11.3), which placed the DART in the "good" to "excellent" category. To our knowledge, the DART platform is the first to use a head-mounted AR system to deliver a dual-task paradigm and simultaneously provide biomechanical data that characterize cognitive and motor performance. Individuals with PD were able to successfully use the DART platform with satisfaction, and dual-task interference was provoked. The DART platform should be investigated as a platform to treat dual-task declines associated with PD.

Effects of Augmented Reality-Based Dual-Task Program on Physical Ability by Cognitive Stage with Developmental Disabilities

People diagnosed with developmental disabilities are less likely to participate in physical activities even if they are provided opportunities. This study aimed to examine the effects of dual-task exercise-based augmented reality (AR) on muscle strength, muscle endurance, balance ability, and flexibility among people with developmental disabilities. Twenty-seven patients with developmental disabilities were included in the study. The intervention was based on an AR-based rehabilitation program and lasted for 8 weeks. The results showed a statistically significant improvement in muscle strength, muscle endurance, balance ability, and flexibility after the intervention (p < 0.05). The AR-based dual-task program increased interest and motivation in the high-cognitive-stage groups, while less interest and motivation were observed in the low-cognitive-stage groups. Our results suggest that an AR-based dual-task program can be an effective method to improve physical ability in patients with high cognitive levels.

Neural Correlates of Dual-Task Processing following Motor Sequence Learning: A Functional Near-Infrared Spectroscopy (fNIRS) Study

The current study used functional near-infrared spectroscopy (fNIRS) to examine cerebral oxygenation changes in the prefrontal cortex (PFC) associated with dual-task processing before and after motor sequence learning. Participants performed self-initiated sequential finger movements that were 4 and 12 units in length with a visual letter-counting task. After practice, dual-task sequence-4 performance revealed decreased activity in the right dorsolateral PFC, medial PFC, and orbitofrontal cortex. However, dual-task sequence-12 performance revealed increased activity in the right ventrolateral PFC when compared to the left hemisphere. The findings suggest that dual-task interference was reduced following practice for dual-task sequence-4. The results also suggest that increased right hemisphere activation is needed to maintain performance when the primary sequential task (e.g., dual-task sequence-12) has a high level of difficulty.

Mobile electroencephalography captures differences of walking over even and uneven terrain but not of single and dual-task gait

Walking on natural terrain while performing a dual-task, such as typing on a smartphone is a common behavior. Since dual-tasking and terrain change gait characteristics, it is of interest to understand how altered gait is reflected by changes in gait-associated neural signatures. A study was performed with 64-channel electroencephalography (EEG) of healthy volunteers, which was recorded while they walked over uneven and even terrain outdoors with and without performing a concurrent task (self-paced button pressing with both thumbs). Data from n = 19 participants (M = 24 years, 13 females) were analyzed regarding gait-phase related power modulations (GPM) and gait performance (stride time and stride time-variability). GPMs changed significantly with terrain, but not with the task. Descriptively, a greater beta power decrease following right-heel strikes was observed on uneven compared to even terrain. No evidence of an interaction was observed. Beta band power reduction following the initial contact of the right foot was more pronounced on uneven than on even terrain. Stride times were longer on uneven compared to even terrain and during dual- compared to single-task gait, but no significant interaction was observed. Stride time variability increased on uneven terrain compared to even terrain but not during single- compared to dual-tasking. The results reflect that as the terrain difficulty increases, the strides become slower and more irregular, whereas a secondary task slows stride duration only. Mobile EEG captures GPM differences linked to terrain changes, suggesting that the altered gait control demands and associated cortical processes can be identified. This and further studies may help to lay the foundation for protocols assessing the cognitive demand of natural gait on the motor system.

Effects of motor-cognitive interaction based on dual-task gait analysis recognition in middle age to aging people with normal cognition and mild cognitive impairment

Background

Mild cognitive impairment (MCI) is considered a transitional stage between cognitive normality and dementia among the elderly, and its associated risk of developing Alzheimer's disease (AD) is 10-15 times higher than that of the general population. MCI is an important threshold for the prevention and control of AD, and intervention in the MCI stage may be the most effective strategy to delay the occurrence of AD.

Materials and methods

In this study, 68 subjects who met the inclusion criteria were divided into an MCI group (38 subjects) and normal elderly (NE) group (30 subjects). Both groups underwent clinical function assessments (cognitive function, walking function, and activities of daily living) and dual-task three-dimensional gait analysis (walking motor task and walking calculation task). Spatial-temporal parameters were obtained and reduced by principal component analysis, and the key biomechanical indexes were selected. The dual-task cost (DTC) was calculated for intra-group (task factor) and inter-group (group factor) comparisons.

Results

The results of the principal component analysis showed that the cadence parameter had the highest weight in all three walking tasks. In addition, there were significant differences in the cadence both walking motor task (WMT) vs. walking task (WT) and walking calculation task (WCT) vs. WT in the MCI group. The cadence in the NE group only showed a significant difference between WMT and WT. The only differences between the MCI group and NE group was DTC cadence in WCT, and no differences were found for cadence in any of the three walking tasks.

Conclusion

The results show that dual tasks based on cognitive-motor gait analysis of DTCcadence in MCI have potential value for application in early identification and provide theoretical support to improve the clinical diagnosis of MCI.