Analyzing gait variability and dual-task interference in patients with Parkinson's disease and freezing by means of the word-color Stroop test

Cognitive-motor dual-task interference in Alzheimer's disease, Parkinson's disease, and prodromal neurodegeneration: A scoping review

BACKGROUND

Cognitive-motor interference (CMI) is a common deficit in Alzheimer's (AD) disease and Parkinson's disease (PD) and may have utility in identification of prodromal neurodegeneration. There is lack of consensus regarding measurement of CMI resulting from dual task paradigms.

RESEARCH QUESTION

How are individuals with AD, PD, and prodromal neurodegeneration impacted by CMI as measured by dual-task (DT) performance?

METHODS

A systematic literature search was performed in six datasets using the PRISMA guidelines. Studies were included if they had samples of participants with AD, PD, or prodromal neurodegeneration and reported at least one measure of cognitive-motor DT performance.

RESULTS

4741 articles were screened and 95 included as part of this scoping review. Articles were divided into three non-mutually exclusive groups based on diagnoses, with 26 articles in AD, 56 articles in PD, and 29 articles in prodromal neurodegeneration, and results presented accordingly.

SIGNIFICANCE

Individuals with AD and PD are both impacted by CMI, though the impact is likely different for each disease. We found a robust body of evidence regarding the utility of measures of DT performance in the detection of subtle deficits in prodromal AD and some signals of utility in prodromal PD. There are several key methodological challenges related to DT paradigms for the measurement of CMI in neurodegeneration. Overall, DT paradigms show good potential as a clinical method to probe specific brain regions, networks, and function; however, task selection and effect measurement should be carefully considered.

Serial Subtraction Alters Lateral Step-down Tibiofemoral Kinematics in Healthy Adults

This study evaluated the effects of two types of cognitive dual-tasking on three-dimensional knee kinematics during the lateral step-down. 19 healthy individuals (22.05±1.61 yrs., 173.92±9.21 cm, 67.99±12.65 kg) participated in this study. Participants completed 5 repetitions of a lateral step-down task for each leg and each testing condition (control, Stroop, and serial subtraction by seven). An electromagnetic motion sensor was attached to the femur via compression clamp placed about the medial and lateral epicondyles. Another sensor was attached 2 cm below the ipsilateral tibial tuberosity. A custom MATLAB algorithm located the knee joint axis of rotation from dynamic knee flexion and extension. Discrete kinematics at peak flexion were used in this study. Paired samples t-tests were used to compare average frontal, transverse, and sagittal plane knee position at maximum flexion between conditions for each leg. No significant differences were found for either limb between control and Stroop conditions. Comparisons revealed significant differences in frontal and transverse plane knee angles at peak flexion between the control and serial subtraction by seven conditions. These findings indicate serial subtraction by seven requires different cognitive processing abilities which may cause greater interference with some aspects of motor control.

Comparison of Wuqinxi Qigong with Stretching on Single- and Dual-Task Gait, Motor Symptoms and Quality of Life in Parkinson’s Disease: A Preliminary Randomized Control Study

The objective of this study was to investigate the therapeutic effect of Wuqinxi Qigong vs. stretching on single- and dual-task gait, motor symptoms, and quality of life in people with mild and moderate Parkinson’s disease (PD). This single-blind, randomized control trial included 40 participants with idiopathic PD who were randomized into the Wuqinxi Qigong (WQ) group or stretching group. Participants completed 12 weeks (two sessions/week) of intervention. The primary outcomes were gait parameters when performing single-task (comfortable pace) and dual-task (obstacle crossing, serial-3 subtraction and backward digit span) walking, including gait speed, stride length, and double support percentage. The secondary outcomes were ratings from the Movement Disorder Society Unified Parkinson’s Disease Rating Scale (MDS-UPDRS), results of the timed-up-and-go test (TUGT), results of the Mini-Balance Evaluation Systems Test (MiniBESTest), and responses from the 39-item Parkinson’s Disease Questionnaire (PDQ-39). All measures were assessed pre- and post-intervention. The WQ group demonstrated increased gait speed (p = 0.000) during the single task, and increased stride length (p = 0.001, p = 0.021) during the single-task and serial-3 subtraction task. Double support percentage significantly decreased (p = 0.004) in the WQ group during the obstacle crossing task, and also decreased (p = 0.045) in the stretching group during the single-task. TUGT (p = 0.005), MiniBESTest (p = 0.023) and PDQ-39 (p = 0.043) in the WQ group significantly improved, and both groups showed significant improvement in MDS-UPDRS after intervention. Wuqinxi Qigong is an effective method to improve single- and dual-task gait. While both exercises improve motor symptoms, Wuqinxi Qigong results in better mobility, balance and quality of life compared to stretching alone.

Dual-task walking reduces lower limb range of motion in individuals with Parkinson's disease and freezing of gait: But does it happen during what events through the gait cycle?

Background

It is unclear how dual-task gait influences the lower limb range of motion (RoM) in people with Parkinson’s disease (PD) and freezing of gait (FOG). The lower limb kinematics during dual-task gait might differ from regular gait, but during what events in the gait cycle?

Methods

This is an observational within-subjects study. Thirty-two individuals with PD and FOG underwent a gait analysis. Single and dual-task gait was assessed by a 3D motion analysis system and the RoM data of the lower limb were extracted from hips, knees and ankles in the sagittal plane. Dual-task assignment was performed using word-color interference test. To compare both gait conditions, we used two different analyses: (1) common discrete analysis to provide lower limb RoM and (2) Statistical Parametric Mapping analysis (SPM) to provide lower limb joint kinematics. A correlation between lower limb RoM and spatiotemporal gait parameters was also performed for each gait condition.

Results

Common discrete analysis evidenced reductions in RoM of hips, knees and ankles during the dual task gait when compared to single gait. SPM analysis showed reductions in flexion-extension of hip, knees and ankles joints when dual task was compared to single task gait. These reductions were observed in specific gait events as toe off (for knees and ankles) and heel strike (for all joints). The reduction in lower limb RoM was positively correlated with the reduction in step length and gait speed.

Conclusions

Lower limb joints kinematics were reduced during toe off and heel strike in dual task gait when compared to single gait. These findings might help physiotherapists to understand the influence of dual and single walking in lower limb RoM throughout the gait cycle in people with PD and FOG.

Plantar stimulation alters brain connectivity in idiopathic Parkinson's disease

OBJECTIVE

Individuals with Parkinson's disease (PD) and freezing of gait (FOG) present peripheral and central sensitivity disturbances that impair motor performance. This study aimed to investigate long-term effects of plantar sensory stimulation on brain activity, brain connectivity, and gait velocity of individuals with PD and FOG.

METHODS

Twenty-five participants were enrolled in this clinical trial (NCT02594540). Plantar sensory stimulation was delivered using the Automated Mechanical Peripheral Stimulation therapy (AMPS). Volunteers were randomly assigned to real or placebo AMPS groups and received eight sessions of treatment. The primary outcome was brain activity (task-based fMRI-active ankle dorsi-plantar flexion). Secondary outcomes were brain connectivity (resting state-RS fMRI) and gait velocity. fMRI was investigated on the left, right, and mid-sensory motor regions, left and right basal ganglia.

RESULTS

No changes in brain activity were observed when task-based fMRI was analyzed. After real AMPS, RS functional connectivity between basal ganglia and sensory-related brain areas increased (insular and somatosensory cortices). Gait velocity also increased after real AMPS. A positive correlation was found between gait velocity and the increased connectivity between sensory, motor and supplementary motor cortices.

CONCLUSION

Plantar sensory stimulation through AMPS was not able to modify brain activity. AMPS increased the RS brain connectivity mainly in areas related to sensory processing and sensorimotor integration. Plantar stimulation could be a way to improve plantar sensitivity and consequently ameliorate gait performance. However, the mechanisms behind the way AMPS influences brain pathways are still not completely known.

Dual-task training on gait, motor symptoms, and balance in patients with Parkinson’s disease: a systematic review and meta-analysis

Objective:

The aim of the present study was to systematically evaluate and quantify the effectiveness of dual-task training on gait parameters, motor symptoms and balance in individuals diagnosed with Parkinson’s disease.

Data resources:

A systematic review of published literature was conducted until May 2020, using PubMed, EMBASE, Cochrane Library, Web of Science, EBSCO and CNKI databases.

Methods:

We included randomized controlled trials (RCTs) and non-RCTs to evaluate the effects of dual-task training compared with those of non-intervention or other forms of training. The measurements included gait parameters, motor symptoms and balance parameters. Methodological quality was assessed using the PEDro scale. Outcomes were pooled by calculating between-group mean differences using fixed- or random-effects models based on study heterogeneity.

Results:

A total of 11 RCTs comprising 322 subjects were included in the present meta-analysis. Results showed that dual-task training significantly improved gait speed (standardized mean difference [SMD], −0.23; 95% confidence interval [CI], −0.38 to −0.08; P = 0.002), cadence (SMD, −0.25; 95% CI, −0.48 to −0.02; P = 0.03), motor symptoms (SMD, 0.56; 95% CI, 0.18 to 0.94; P = 0.004) and balance (SMD, −0.44; 95% CI, −0.84 to −0.05; P = 0.03). However, no significant changes were detected in step length or stride length.

Conclusion:

Dual-task training was effective in improving gait performance, motor symptoms and balance in patients with Parkinson’s disease relative to other forms of training or non-intervention.

Behavioural manifestations and associated non-motor features of freezing of gait: A narrative review and theoretical framework

Over the past decade, non-motor related symptoms and provocative contexts have offered unique opportunities to gain insight into the potential mechanisms that may underpin freezing of gait (FOG) in Parkinson's disease (PD). While this large body of work has informed several theoretical models, to date, few are capable of explaining behavioural findings across multiple domains (i.e. cognitive, sensory-perceptual and affective) and in different behavorial contexts. As such, the exact nature of these interrelationships and their neural basis remain quite enigmatic. Here, the non-motor, behavioural evidence for cognitive, sensory-perceptual and affective contributors to FOG are reviewed and synthesized by systematically examining (i) studies that manipulated contextual environments that provoke freezing of gait, (ii) studies that uncovered factors that have been proposed to contribute to freezing, and (iii) studies that longitudinally tracked factors that predict the future development of freezing of gait. After consolidating the evidence, we offer a novel perspective for integrating these multi-faceted behavioural patterns and identify key challenges that warrant consideration in future work.

Automated Mechanical Peripheral Stimulation Effects on Gait Variability in Individuals With Parkinson Disease and Freezing of Gait: A Double-Blind, Randomized Controlled Trial

OBJECTIVE

To assess the effects of automated peripheral stimulation (AMPS) in reducing gait variability of subjects with Parkinson disease (PD) and freezing of gait (FOG) treated with AMPS and to explore the effects of this treatment on gait during a single task (walking) and a dual task (walking while attending the word-color Stroop test).

DESIGN

Interventional, double-blinded, placebo-controlled, randomized trial.

SETTING

Clinical rehabilitation.

PARTICIPANTS

Thirty subjects were randomized into 2 groups: AMPS (n=15) and AMPS sham (n=15).

INTERVENTIONS

Both groups received 2 treatment sessions a week for 4 consecutive weeks (totaling 8 treatment sessions). AMPS was applied by using a medical device (Gondola™) and consisted in mechanical pressure stimulations delivered by metallic actuators on 4 areas of the feet. Treatment parameters and device configuration were modified for AMPS sham group.

MAIN OUTCOME MEASURES

Gait analyses were measured at baseline and after the first, fourth, and eighth treatment sessions.

RESULTS

Interactions among groups and sessions were found for both conditions while off anti-Parkinsonian medications. AMPS decreased gait variability in subjects with PD and FOG for both single and dual task conditions.

CONCLUSIONS

AMPS is an effective add-on therapy for treating gait variability in patients with PD and FOG.