Does Stroke Severity Influence Sensory Feedback Needed for Reaching?
Document Type
Event
Abstract
In this study, we looked at comparing reaching performance of individuals with different impairment levels post-stroke. Our aim was to see the extent an individual relied on sensory feedback to complete a reaching task and see if it correlated with stroke impairment levels. We categorized 55 individuals post-stoke as mild, moderate or severe based on a standard measure used in rehabilitation, the Fugl-Meyer Assessment. We used 3-D motion analysis with 12 cameras, 33 reflective markers, and 16 EMG sensors to get kinematic data of the participant while reaching. In a neurologically typical person, a graphical representation of reach velocity is a bell-shaped curve. Equal time is spent in both the feedforward and feedback phases of the reach. Feedforward is defined as processing external stimuli and executing a motor plan. The feedback phase of a reach is when the participant processes additional external stimuli (movement speed, trajectory, angles, etc) during a reach and makes corrections to the initial plan as needed. We measured two independent variables. The first was percent at which peak velocity (PPV) occurs (peak velocity /total movement time), which corresponds to how much of the movement is preplanned and continuous. Another variable is time post peak velocity (TPPV), which shows alterations in the original motor plan based on sensory feedback (increased TPPV = increased reliance on sensory feedback). We found that PPV was significantly (p<.05) decreased in moderate and severe impairment groups when compared to the control. Additionally, TPPV was significantly larger in the severe group when compared to the control. These findings reinforce the reliance a stroke survivor has on sensory feedback to execute a motor task and may guide therapeutic interventions to improve outcomes.
Does Stroke Severity Influence Sensory Feedback Needed for Reaching?
Breakout Session B: Health Sciences II
CASB 101In this study, we looked at comparing reaching performance of individuals with different impairment levels post-stroke. Our aim was to see the extent an individual relied on sensory feedback to complete a reaching task and see if it correlated with stroke impairment levels. We categorized 55 individuals post-stoke as mild, moderate or severe based on a standard measure used in rehabilitation, the Fugl-Meyer Assessment. We used 3-D motion analysis with 12 cameras, 33 reflective markers, and 16 EMG sensors to get kinematic data of the participant while reaching. In a neurologically typical person, a graphical representation of reach velocity is a bell-shaped curve. Equal time is spent in both the feedforward and feedback phases of the reach. Feedforward is defined as processing external stimuli and executing a motor plan. The feedback phase of a reach is when the participant processes additional external stimuli (movement speed, trajectory, angles, etc) during a reach and makes corrections to the initial plan as needed. We measured two independent variables. The first was percent at which peak velocity (PPV) occurs (peak velocity /total movement time), which corresponds to how much of the movement is preplanned and continuous. Another variable is time post peak velocity (TPPV), which shows alterations in the original motor plan based on sensory feedback (increased TPPV = increased reliance on sensory feedback). We found that PPV was significantly (p<.05) decreased in moderate and severe impairment groups when compared to the control. Additionally, TPPV was significantly larger in the severe group when compared to the control. These findings reinforce the reliance a stroke survivor has on sensory feedback to execute a motor task and may guide therapeutic interventions to improve outcomes.