Ankle-foot orthoses improve walking but do not reduce dual-task costs after stroke (original) (raw)

Dual task interference while walking in chronic stroke survivors

Physical Therapy Rehabilitation Science

Objective: Dual-task interference is defined as decrements in performance observed when people attempt to perform two tasks concurrently, such as a verbal task and walking. The purpose of this study was to investigate the changes of gait ability according to the dual task interference in chronic stroke survivors. Design: Cross-sectional study. Methods: Ten chronic stroke survivors (9 male, 1 female; mean age, 55.30 years; mini mental state examination, 19.60; onset duration, 56.90 months) recruited from the local community participated in this study. Gait ability (velocity, paretic side step, and stride time and length) under the single-and dual-task conditions at a self-selected comfortable walking speed was measured using the motion analysis system. In the dual task conditions, subjects performed three types of cognitive tasks (controlled oral word association test, auditory clock test, and counting backwards) while walking on the track. Results: For velocity, step and stride length, there was a significant decrease in the dual-task walking condition compared to the single walking condition (p<0.05). In particular, higher reduction of walking ability was observed when applying the counting backward task. Conclusions: Our results revealed that the addition of cognitive tasks while walking may lead to decrements of gait ability in stroke survivors. In particular, the difficulty level was the highest for the calculating task. We believe that these results provide basic information for improvements in gait ability and may be useful in gait training to prevent falls after a stroke incident.

Interactions between cognitive tasks and gait after stroke: A dual task study

Gait & Posture, 2008

This study investigated the interactions between gait and three different cognitive tasks in people after stroke. Thirteen people post-stroke who were living in the community, were able to walk 10 m without physical assistance, and could respond verbally to auditory stimuli participated. Participants performed a walking task alone, three different cognitive tasks while seated, and each cognitive task in combination with walking. Gait data were acquired continuously for approximately 3 min. Reaction time and accuracy were recorded for two of the cognitive tasks (visuospatial task, working memory task). Speech samples from the spontaneous speech task were analyzed on several dimensions of language. Significant dual task effects were observed for gait speed, stride time, average stride length, and cadence, but not for stride time variability. Speech produced more gait interference than memory and visuospatial tasks. Interference effects on cognition were minimal; only speech was significantly affected by concurrent walking. Narratives in the dual task condition had more pauses, shorter sentences, but more utterances with new information. Even though participants in this study were mobility-impaired, they prioritized the cognitive tasks. Future research should determine whether dual task training can reduce gait decrements in dual task situations in people after stroke.

Cognitive-Motor Interference During Functional Mobility After Stroke: State of the Science and Implications for Future Research

Archives of Physical Medicine and Rehabilitation, 2013

Cognitive-motor interference (CMI) is evident when simultaneous performance of a cognitive task and a motor task results in deterioration in performance in one or both of the tasks, relative to performance of each task separately. The purpose of this review is to present a framework for categorizing patterns of CMI and to examine the specific patterns of CMI evident in published studies comparing single-task and dual-task performance of cognitive and motor tasks during gait and balance activities after stroke. We also examine the literature for associations between patterns of CMI and a history of falls, as well as evidence for the effects of rehabilitation on CMI after stroke. Overall, this review suggests that during gait activities with an added cognitive task, people with stroke are likely to demonstrate significant decrements in motor performance only (cognitive-related motor interference), or decrements in both motor and cognitive performance (mutual interference). In contrast, patterns of CMI were variable among studies examining balance activities. Comparing people poststroke with and without a history of falls, patterns and magnitude of CMI were similar for fallers and nonfallers. Longitudinal studies suggest that conventional rehabilitation has minimal effects on CMI during gait or balance activities. However, early-phase pilot studies suggest that dual-task interventions may reduce CMI during gait performance in community-dwelling stroke survivors. It is our hope that this innovative and critical examination of the existing literature will highlight the limitations in current experimental designs and inform improvements in the design and reporting of dual-task studies in stroke.

Cognitive motor interference while walking: A systematic review and meta-analysis

Neuroscience and Biobehavioral Reviews, 2011

Dual-task methodology has been increasingly used to assess cognitive motor interference while walking. However, whether the observed dual-task-related gait changes are systematically related to methodological variations remains unclear and researchers still lack knowledge of what cognitive task to use in different groups for clinical purposes or for research. We systematically reviewed experimental studies that measured gait performance with and without performing concurrent cognitive task. Our results suggest that cognitive tasks that involve internal interfering factors seem to disturb gait performance more than those involving external interfering factors. Meta-analysis results show that the overall effect of different cognitive tasks was prominent in gait speed. In healthy participants, meta-regression analysis suggests strong associations between age and speed reduction under dual-task conditions and between the level of cognitive state and speed reduction under dual-task conditions. Standardizing research methodologies, as well as improving their ecological validity, enables better understanding of dualtask-related gait changes in different populations and improves, in turn, our understanding of neural mechanisms and gait control in general in content.

Cognitive-Locomotor Dual-Task Interference in Stroke Survivors and the Influence of the Tasks: A Systematic Review

Frontiers in Neurology, 2020

Background: Walking in the community can be challenging for stroke survivors. The fact that community walking often requires performing another task while walking further adds to this challenge and can lead to a deterioration of performance in one or both tasks. Objective: To review the existing literature about cognitive-locomotor dual-task interference (DTI) magnitude and pattern while walking in patients with stroke and to explore the influence of tasks' nature on DTI. Moreover, this review investigated the differences in DTI between stroke survivors and age-matched healthy adults. Methods: The literature search was conducted in 4 databases (MEDLINE, CINAHL, EMBASE and PEDro). Two authors independently identified relevant studies based on predetermined selection criteria. Among these criteria, studies had to include both locomotor and cognitive DTI. Methodological quality of the studies was independently assessed by two raters using a standardized checklist. Studies were categorized according to the nature of the locomotor and the cognitive tasks. Results: A total of twenty studies, with good to high methodological quality, were selected. Task combinations, outcome measures and participants characteristics varied widely from one study to another. Despite heterogeneous results across studies, mutual DTI (decrements in both locomotor and cognitive performance) was the most frequently observed pattern in participants with stroke. Interestingly, this DTI pattern was systematically obtained when participants had to avoid obstacles while walking. DTI seemed also to be influenced by the nature of the cognitive task. Compared to age-matched healthy participants, stroke survivors had greater DTI. Mutual interferences were also more frequently observed in stroke survivors than in age-matched healthy adults. Conclusions: DTI magnitude and pattern in persons with stroke varied considerably across studies. Multiple factors, including nature of the tasks, may influence dual-task abilities when assessing individuals with stroke. Consequently, dual-task assessments should be performed in similar contexts of individuals' daily lives to ensure ecological validity.

Measuring treatment effects on dual-task performance: a framework for research and clinical practice

Frontiers in Human Neuroscience, 2015

The relevance of dual-task walking to everyday ambulation is widely acknowledged, and numerous studies have demonstrated that dual-task interference can significantly impact recovery of functional walking in people with neurological disorders. The magnitude and direction of dual-task interference is influenced by the interaction between the two tasks, including how individuals spontaneously prioritize their attention. Therefore, to accurately interpret and characterize dual-task interference and identify changes over time, it is imperative to evaluate single and dual-task performance in both tasks, as well as the tasks relative to each other. Yet, reciprocal dual-task effects (DTE) are frequently ignored. The purpose of this perspective paper is to present a framework for measuring treatment effects on dual-task interference, specifically taking into account the interactions between the two tasks and how this can provide information on whether overall dual-task capacity has improved or a different attentional strategy has been adopted. In discussing the clinical implications of using this framework, we provide specific examples of using this method and provide some explicit recommendations for research and clinical practice.

Cognitive motor interference for gait and balance in stroke: a systematic review and meta‐analysis

Background and purpose: An increasing interest in the potential benefits of cognitive motor interference (CMI) for stroke has recently been observed, but the efficacy of CMI for gait and balance is controversial. A systematic review and meta-analysis of randomized controlled trials was performed to estimate the effect of CMI on gait and balance in patients with stroke. Methods: Articles in Medline, EMBASE, the Cochrane Library, Web of Science, CINAHL, PEDro and the China Biology Medicine disc were searched from 1970 to July 2014. Only randomized controlled trials examining the effects of CMI for patients with stroke were included, and no language restrictions were applied. Main outcome measures included gait and balance function. Results: A total of 15 studies composed of 395 participants met the inclusion criteria, and 13 studies of 363 participants were used as data sources for the meta-analysis. Pooling revealed that CMI was superior to the control group for gait speed [mean difference (MD) 0.19 m/s, 95% confidence interval (CI) (0.06, 0.31), P = 0.003], stride length [MD 12.53 cm, 95% CI (4.07, 20.99), P = 0.004], cadence [MD 10.44 steps/min, 95% CI (4.17, 16.71), P = 0.001], centre of pressure sway area [MD À1.05, 95% CI (À1.85, À0.26), P = 0.01] and Berg balance scale [MD 2.87, 95% CI (0.54, 5.21), P = 0.02] in the short term. Conclusion: Cognitive motor interference is effective for improving gait and balance function for stroke in the short term. However, only little evidence supports assumptions regarding CMI's long-term benefits.

A randomised controlled trial of a walking training with simultaneous cognitive demand (dual task) in chronic stroke

European journal of neurology, 2018

To evaluate the tolerability of, adherence to and efficacy of a community walking training programme with simultaneous cognitive demand (dual-task) compared to a control walking training programme without cognitive distraction. Adult stroke survivors, at least 6 months after stroke with a visibly obvious gait abnormality or reduced two-minute walk distance were included into a 2-arm parallel randomized controlled trial of complex intervention with blinded assessments. Participants received a 10 week, bi-weekly, 30 minutes treadmill program at an aerobic training intensity (55-85% heart rate maximum), either with, or without simultaneous cognitive demands. Outcome measured at 0, 11 and 22 weeks. Primary: two-minute-walk tests with and without cognitive distraction, dual task effect on walking and cognition; secondary: SF-36, EuroQol-5D-5L, Physical Activity Scale for Elderly (PASE), and step activity. Fifty stroke patients were included, 43 received allocated training and 45 complete...