Kerry Clifton | Dalhousie University (original) (raw)
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Topics in Stroke Rehabilitation , 2020
Background: Cognitive-motor interference, as measured by dual-task walking (performing a mental t... more Background: Cognitive-motor interference, as measured by dual-task walking (performing a mental task while walking), affects many clinical populations. Ankle-foot orthoses (AFOs) are lower-leg splints prescribed to provide stability to the foot and ankle, as well as prevent foot drop, a gait deficit common after stroke. AFO use has been shown to improve gait parameters such as speed and step time, which are often negatively impacted by dual-task walking. Objectives: Our objective was to establish whether AFOs could protect against cognitive-motor interference, as measured by dual-task walking, following post-stroke hemiplegia. Methods: A total of 21 individuals with post-stroke hemiplegia that use an AFO completed a dual-task walking paradigm in the form of a 2 (walking with vs. without a concurrent cognitive task) by 2 (walking with vs. without an AFO) repeated-measures design. Changes to both motor and cognitive performance were analyzed. Results: The results suggest that the use of an AFO improves gait overall in both single-and dual-task walking, particularly with respect to stride regularity, but there were no interactions to suggest that AFOs reduce the cognitive-motor dual-task costs themselves. A lack of differences in cognitive performance during dual-task walking with and without the AFO suggests that the AFO's benefit to motor performance cannot be attributed to task prioritization. Conclusions: These data support the use of AFOs to improve certain gait parameters for post-stroke hemiplegia, but AFOs do not appear to protect against cognitive-motor interference during dual-task walking. Future research should pursue alternate therapeutics for ameliorating task-specific declines under cognitively demanding circumstances.
Archives of Physical Medicine and Rehabilitation, 2013
Cognitive-motor interference (CMI) is evident when simultaneous performance of a cognitive task a... more 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.
Topics in Stroke Rehabilitation , 2020
Background: Cognitive-motor interference, as measured by dual-task walking (performing a mental t... more Background: Cognitive-motor interference, as measured by dual-task walking (performing a mental task while walking), affects many clinical populations. Ankle-foot orthoses (AFOs) are lower-leg splints prescribed to provide stability to the foot and ankle, as well as prevent foot drop, a gait deficit common after stroke. AFO use has been shown to improve gait parameters such as speed and step time, which are often negatively impacted by dual-task walking. Objectives: Our objective was to establish whether AFOs could protect against cognitive-motor interference, as measured by dual-task walking, following post-stroke hemiplegia. Methods: A total of 21 individuals with post-stroke hemiplegia that use an AFO completed a dual-task walking paradigm in the form of a 2 (walking with vs. without a concurrent cognitive task) by 2 (walking with vs. without an AFO) repeated-measures design. Changes to both motor and cognitive performance were analyzed. Results: The results suggest that the use of an AFO improves gait overall in both single-and dual-task walking, particularly with respect to stride regularity, but there were no interactions to suggest that AFOs reduce the cognitive-motor dual-task costs themselves. A lack of differences in cognitive performance during dual-task walking with and without the AFO suggests that the AFO's benefit to motor performance cannot be attributed to task prioritization. Conclusions: These data support the use of AFOs to improve certain gait parameters for post-stroke hemiplegia, but AFOs do not appear to protect against cognitive-motor interference during dual-task walking. Future research should pursue alternate therapeutics for ameliorating task-specific declines under cognitively demanding circumstances.
Archives of Physical Medicine and Rehabilitation, 2013
Cognitive-motor interference (CMI) is evident when simultaneous performance of a cognitive task a... more 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.