Limits...
Effect of auditory constraints on motor performance depends on stage of recovery post-stroke.

Aluru V, Lu Y, Leung A, Verghese J, Raghavan P - Front Neurol (2014)

Bottom Line: In contrast, in spastic co-contraction, no auditory stimulation increased wrist extension and reduced co-activation.In minimal paresis, wrist extension did not improve under any condition.The findings advance our understanding of the mechanisms of progression of motor recovery and lay the foundation for personalized treatment algorithms post-stroke.

View Article: PubMed Central - PubMed

Affiliation: Department of Rehabilitation Medicine, New York University School of Medicine , New York, NY , USA.

ABSTRACT
In order to develop evidence-based rehabilitation protocols post-stroke, one must first reconcile the vast heterogeneity in the post-stroke population and develop protocols to facilitate motor learning in the various subgroups. The main purpose of this study is to show that auditory constraints interact with the stage of recovery post-stroke to influence motor learning. We characterized the stages of upper limb recovery using task-based kinematic measures in 20 subjects with chronic hemiparesis. We used a bimanual wrist extension task, performed with a custom-made wrist trainer, to facilitate learning of wrist extension in the paretic hand under four auditory conditions: (1) without auditory cueing; (2) to non-musical happy sounds; (3) to self-selected music; and (4) to a metronome beat set at a comfortable tempo. Two bimanual trials (15 s each) were followed by one unimanual trial with the paretic hand over six cycles under each condition. Clinical metrics, wrist and arm kinematics, and electromyographic activity were recorded. Hierarchical cluster analysis with the Mahalanobis metric based on baseline speed and extent of wrist movement stratified subjects into three distinct groups, which reflected their stage of recovery: spastic paresis, spastic co-contraction, and minimal paresis. In spastic paresis, the metronome beat increased wrist extension, but also increased muscle co-activation across the wrist. In contrast, in spastic co-contraction, no auditory stimulation increased wrist extension and reduced co-activation. In minimal paresis, wrist extension did not improve under any condition. The results suggest that auditory task constraints interact with stage of recovery during motor learning after stroke, perhaps due to recruitment of distinct neural substrates over the course of recovery. The findings advance our understanding of the mechanisms of progression of motor recovery and lay the foundation for personalized treatment algorithms post-stroke.

No MeSH data available.


Related in: MedlinePlus

Group means computed for the first trial with the paretic hand. (A) Speed of wrist extension in degrees per second; (B) extent of wrist extension in degrees; (C) root mean square of wrist extensor muscle activation during wrist extension; (D) root mean square of wrist flexor muscle activation during wrist extension; (E) log of wrist co-activation computed as ratio of wrist flexor to extensor muscle activation. The blue bars represent the group with spastic paresis, which had the lowest Fugl-Meyer scores, the red bars represent the spastic co-contraction group with intermediate Fugl-Meyer scores, and the green bars represent the minimal paresis group, which had the highest Fugl-Meyer scores. Values for the non-paretic hand are shown in gray for reference. Error bars represent the standard error. *Represents differences between the three groups at p < 0.05, and +represents differences between the three groups at p < 0.1.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4066443&req=5

Figure 4: Group means computed for the first trial with the paretic hand. (A) Speed of wrist extension in degrees per second; (B) extent of wrist extension in degrees; (C) root mean square of wrist extensor muscle activation during wrist extension; (D) root mean square of wrist flexor muscle activation during wrist extension; (E) log of wrist co-activation computed as ratio of wrist flexor to extensor muscle activation. The blue bars represent the group with spastic paresis, which had the lowest Fugl-Meyer scores, the red bars represent the spastic co-contraction group with intermediate Fugl-Meyer scores, and the green bars represent the minimal paresis group, which had the highest Fugl-Meyer scores. Values for the non-paretic hand are shown in gray for reference. Error bars represent the standard error. *Represents differences between the three groups at p < 0.05, and +represents differences between the three groups at p < 0.1.

Mentions: Baseline performance metrics on the wrist extension task also showed clear differences across the three groups. Movement speed was higher in group 3 compared to groups 1 and 2 (p < 0.001, Figure 4A). Extent of wrist extension was lowest in group 2 (where attempted wrist extension produced paradoxical flexion), intermediate in group 1, and highest in group 3 (p < 0.001, Figure 4B). Wrist extensor muscle (ECRL) activation was also lowest in group 2, intermediate in group 1, and highest in group 3 (p = 0.047, Figure 4C), whereas wrist flexor muscle (FCU) activation was not differentiated in the three groups (p = 0.877, Figure 4D). Co-activation between wrist extensor and flexor muscles was highest in group 2, intermediate in group 1, and lowest in group 3 (p = 0.07, Figure 4E). Taken together, the baseline performance and clinical metrics enabled characterization of recovery patterns into the three descriptive groups below.


Effect of auditory constraints on motor performance depends on stage of recovery post-stroke.

Aluru V, Lu Y, Leung A, Verghese J, Raghavan P - Front Neurol (2014)

Group means computed for the first trial with the paretic hand. (A) Speed of wrist extension in degrees per second; (B) extent of wrist extension in degrees; (C) root mean square of wrist extensor muscle activation during wrist extension; (D) root mean square of wrist flexor muscle activation during wrist extension; (E) log of wrist co-activation computed as ratio of wrist flexor to extensor muscle activation. The blue bars represent the group with spastic paresis, which had the lowest Fugl-Meyer scores, the red bars represent the spastic co-contraction group with intermediate Fugl-Meyer scores, and the green bars represent the minimal paresis group, which had the highest Fugl-Meyer scores. Values for the non-paretic hand are shown in gray for reference. Error bars represent the standard error. *Represents differences between the three groups at p < 0.05, and +represents differences between the three groups at p < 0.1.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4066443&req=5

Figure 4: Group means computed for the first trial with the paretic hand. (A) Speed of wrist extension in degrees per second; (B) extent of wrist extension in degrees; (C) root mean square of wrist extensor muscle activation during wrist extension; (D) root mean square of wrist flexor muscle activation during wrist extension; (E) log of wrist co-activation computed as ratio of wrist flexor to extensor muscle activation. The blue bars represent the group with spastic paresis, which had the lowest Fugl-Meyer scores, the red bars represent the spastic co-contraction group with intermediate Fugl-Meyer scores, and the green bars represent the minimal paresis group, which had the highest Fugl-Meyer scores. Values for the non-paretic hand are shown in gray for reference. Error bars represent the standard error. *Represents differences between the three groups at p < 0.05, and +represents differences between the three groups at p < 0.1.
Mentions: Baseline performance metrics on the wrist extension task also showed clear differences across the three groups. Movement speed was higher in group 3 compared to groups 1 and 2 (p < 0.001, Figure 4A). Extent of wrist extension was lowest in group 2 (where attempted wrist extension produced paradoxical flexion), intermediate in group 1, and highest in group 3 (p < 0.001, Figure 4B). Wrist extensor muscle (ECRL) activation was also lowest in group 2, intermediate in group 1, and highest in group 3 (p = 0.047, Figure 4C), whereas wrist flexor muscle (FCU) activation was not differentiated in the three groups (p = 0.877, Figure 4D). Co-activation between wrist extensor and flexor muscles was highest in group 2, intermediate in group 1, and lowest in group 3 (p = 0.07, Figure 4E). Taken together, the baseline performance and clinical metrics enabled characterization of recovery patterns into the three descriptive groups below.

Bottom Line: In contrast, in spastic co-contraction, no auditory stimulation increased wrist extension and reduced co-activation.In minimal paresis, wrist extension did not improve under any condition.The findings advance our understanding of the mechanisms of progression of motor recovery and lay the foundation for personalized treatment algorithms post-stroke.

View Article: PubMed Central - PubMed

Affiliation: Department of Rehabilitation Medicine, New York University School of Medicine , New York, NY , USA.

ABSTRACT
In order to develop evidence-based rehabilitation protocols post-stroke, one must first reconcile the vast heterogeneity in the post-stroke population and develop protocols to facilitate motor learning in the various subgroups. The main purpose of this study is to show that auditory constraints interact with the stage of recovery post-stroke to influence motor learning. We characterized the stages of upper limb recovery using task-based kinematic measures in 20 subjects with chronic hemiparesis. We used a bimanual wrist extension task, performed with a custom-made wrist trainer, to facilitate learning of wrist extension in the paretic hand under four auditory conditions: (1) without auditory cueing; (2) to non-musical happy sounds; (3) to self-selected music; and (4) to a metronome beat set at a comfortable tempo. Two bimanual trials (15 s each) were followed by one unimanual trial with the paretic hand over six cycles under each condition. Clinical metrics, wrist and arm kinematics, and electromyographic activity were recorded. Hierarchical cluster analysis with the Mahalanobis metric based on baseline speed and extent of wrist movement stratified subjects into three distinct groups, which reflected their stage of recovery: spastic paresis, spastic co-contraction, and minimal paresis. In spastic paresis, the metronome beat increased wrist extension, but also increased muscle co-activation across the wrist. In contrast, in spastic co-contraction, no auditory stimulation increased wrist extension and reduced co-activation. In minimal paresis, wrist extension did not improve under any condition. The results suggest that auditory task constraints interact with stage of recovery during motor learning after stroke, perhaps due to recruitment of distinct neural substrates over the course of recovery. The findings advance our understanding of the mechanisms of progression of motor recovery and lay the foundation for personalized treatment algorithms post-stroke.

No MeSH data available.


Related in: MedlinePlus