Performance of discrete, reciprocal, and cyclic movements of the ipsilesional upper limb in individuals after stroke (original) (raw)
Related papers
Ipsilesional Arm Aiming Movements After Stroke: Influence of the Degree of Contralesional Impairment
Journal of Motor Behavior, 2017
The authors examined the effects of the degree of impairment of the contralesional upper limb and the side of the hemispheric damage on ipsilesional upper limb performance in chronic stroke individuals. Right-and left-side stroke resulting in mild-to-severe impairment and healthy participants took part in simple and choice reaction time tasks involving aiming movements. The stroke individuals performed the aiming movements with the ipsilesional upper limb using a digitizing tablet to ipsi-or contralateral targets presented in a monitor. The global performance of the group with severe right hemispheric damage was worse than that of the other groups, indicating that the side of hemispheric damage and degree of motor impairment can adversely affect aiming movement performance.
Targeted Aiming Movements Are Compromised in Nonaffected Limb of Persons With Stroke
Neurorehabilitation and Neural Repair, 2007
Background. Research has shown that movement impairments following stroke are typically associated with the limb contralateral to the side of the stroke. Prior studies identified ipsilateral motor declines across a variety of tasks. Objective. Two experiments were conducted to better understand the ipsilateral contributions to organization and execution of proximal upper extremity multisegment aiming movements in persons with right-hemispheric stroke. Methods. Participants performed reciprocal aiming (Experiment 1) and 2-segment aiming movements (Experiment 2) on a digitizing tablet. In both experiments, target size and/or target orientation were manipulated to examine the influence of accuracy constraints on the planning and organization of movements. Results. Kinematic measures, submovement analysis, and harmonicity measures were included in this study. Declines in organization and execution of multisegment movements were found to contribute to performance decrements and slowing in stroke patients. Furthermore, stroke patients were unable to efficiently plan multisegment movements as one functional unit, resulting in discrete movements. Conclusions. Results suggest the importance of considering ipsilateral contributions to the control and organization of targeted aiming movements as well as implications for rehabilitation and recovery.
Effects of Direction and Index of Difficulty on Aiming Movements after Stroke
Behavioural Neurology, 2014
Background. Brain hemispheres play different roles in the control of aiming movements that are impaired after unilateral stroke. It is not clear whether those roles are influenced by the direction and the difficulty of the task. Objective. To evaluate the influence of direction and index of difficulty (ID) of the task on performance of ipsilesional aiming movements after unilateral stroke. Methods. Ten individuals with right hemisphere stroke, ten with left hemisphere stroke, and ten age-and gender-matched controls performed the aiming movements on a digitizing tablet as fast as possible. Stroke individuals used their ipsilesional arm. The direction (ipsilateral or contralateral), size (0.8 or 1.6 cm), and distance (9 or 18 cm) of the targets, presented on a monitor, were manipulated and determined to be of different ID (3.5, 4.5, and 5.5). Results. Individuals with right hemisphere lesion were more sensitive to ID of the task, affecting planning and final position accuracy. Left hemisphere lesion generated slower and less smooth movements and was more influenced by target distance. Contralateral movements and higher ID increased planning demands and hindered movement execution. Conclusion. Right and left hemisphere damages are differentially influenced by task constraints which suggest their complementary roles in the control of aiming movements.
Journal of Clinical Medical Research, 2023
Background: A substantial amount of descriptive, rehabilitation and review research examined the behavioral (kinematic) nature of intra-limb organization in reaching and grasping actions in individuals who suffered a stroke. However, the majority of this work failed to explicitly address the level of movement organization affected, the conceptual relevance to existing theories of motor control, and the impact of different constraints on the emerging actions. Thus, the purpose was to examine whether the selected studies examined the issue in coordination and/or control, in the context of the existing conceptual frameworks. The second purpose was to delineate which individual and task constraints have been examined in previous work, and infer the degree to which these factors affected the nature of the emerging movement patterns. Methods: The search of four databases (PubMed, Embase, Web of Science and CINAHL), including published work between January 2019 and March 2022, yielded twenty studies. Results: Despite the fact that stroke substantially alters the emerging movement patterns majority of the studies examined issues in control, not coordination. In term of spatial and temporal control, the actions of individuals with stroke were slower and involved minimal use of the shoulder and elbow joints, as compared to their healthy counterparts. The analysis of emerging movement patterns, via inverse kinematics, showed that stroke resulted in segmented coordination between shoulder and elbow, while no studies examined the relations between distal anatomical structures (e.g., elbow and wrist). In terms of specific theories or models of motor control, most research was data-driven as only three studies made inferences to existing motor control theories (e.g., Equilibrium Point Hypothesis). In regards to the second purpose, time after stroke was the most impactful individual constraint which differentiated the nature of movement organization exhibited by those with and without stroke. The impact of variables such as gender and age, on performance of individuals with stroke, was not examined. From the methodological standpoint, lack of measures of intra-individual variability represents an important limitation in rehabilitation research reviewed. Conclusion: Collectively, the understanding of how individuals with stroke organize their actions remains equivocal. This is due to a variety of different methodological approaches used (e.g., forward vs. inverse kinematics), limited insight into critical aspects of movement organization (e.g., coordination) and the effects of key individual constraints (e.g., age/gender) on the nature of emerging movements. Also, the fact that data driven research still represents the primary impetus in this clinical field undermines the validity of the emerging inferences.
Contralesional motor deficits after unilateral stroke reflect hemisphere-specific control mechanisms
Brain, 2013
We have proposed a model of motor lateralization, in which the left and right hemispheres are specialized for different aspects of motor control: the left hemisphere for predicting and accounting for limb dynamics and the right hemisphere for stabilizing limb position through impedance control mechanisms. Our previous studies, demonstrating different motor deficits in the ipsilesional arm of stroke patients with left or right hemisphere damage, provided a critical test of our model. However, motor deficits after stroke are most prominent on the contralesional side. Post-stroke rehabilitation has also, naturally, focused on improving contralesional arm impairment and function. Understanding whether contralesional motor deficits differ depending on the hemisphere of damage is, therefore, of vital importance for assessing the impact of brain damage on function and also for designing rehabilitation interventions specific to laterality of damage. We, therefore, asked whether motor deficits in the contralesional arm of unilateral stroke patients reflect hemisphere-dependent control mechanisms. Because our model of lateralization predicts that contralesional deficits will differ depending on the hemisphere of damage, this study also served as an essential assessment of our model. Stroke patients with mild to moderate hemiparesis in either the left or right arm because of contralateral stroke and healthy control subjects performed targeted multi-joint reaching movements in different directions. As predicted, our results indicated a double dissociation; although left hemisphere damage was associated with greater errors in trajectory curvature and movement direction, errors in movement extent were greatest after right hemisphere damage. Thus, our results provide the first demonstration of hemisphere specific motor control deficits in the contralesional arm of stroke patients. Our results also suggest that it is critical to consider the differential deficits induced by right or left hemisphere lesions to enhance post-stroke rehabilitation interventions.
The co-ordination of bimanual rapid aiming movements following stroke
Clinical Rehabilitation, 2005
Objective: To determine the role of anticipatory and movement control processes for the coordination of bimanual target aiming in individuals post stroke. Subjects: Thirty adults with chronic stroke and 30 individuals without stroke history. Design: A two-group (stroke, control) by two-aiming type (unimanual, bimanual) by two-limb (paretic, nonparetic; left, right for controls) design with repeated measures on the last two factors. Outcome measures: Kinematic analyses of performance and psychometric measures of reaction time, movement time, peak resultant velocity, time to and after peak resultant velocity and interlimb timing for movement initiation and target impact. Results: Compared with unimanual aiming, the nonparetic limb exhibited a prolonged movement time in the bimanual condition; the locus for prolongation was primarily in the deceleration phase. This adaptive response allowed for a nearly simultaneous (both limbs) target impact in 81% of trials. Compared with the unimanu...
Directional and general impairments in initiating motor responses after stroke
Brain Communications
Visuospatial neglect is a disorder characterized by an impairment of attention, most commonly to the left side of space in individuals with stroke or injury to the right hemisphere. Clinical diagnosis is largely based on performance on pen and paper examinations that are unable to accurately measure the speed of processing environmental stimuli—important for interacting in our dynamic world. Numerous studies of impairment after visuospatial neglect demonstrate delayed reaction times when reaching to the left. However, little is known of the visuospatial impairment in other spatial directions and, further, the influence of the arm being assessed. In this study, we quantify the ability of a large cohort of 204 healthy control participants (females = 102) and 265 individuals with stroke (right hemisphere damage = 162, left hemisphere damage = 103; mean age 62) to generate goal-directed reaches. Participants used both their contralesional and ipsilesional arms to perform a centre-out vi...
Temporal structure of variability decreases in upper extremity movements post stroke
Clinical Biomechanics, 2013
Background: The objective of this study was to determine movement variability in the more-affected upper-extremity in chronic stroke survivors. We investigated two hypotheses: (1) individuals with stroke will have increased amount of variability and altered structure of variability in upper-extremity joint movement patterns as compared to age-matched controls; and (2) the degree of motor impairment and joint kinematics will be correlated with the temporal structure of variability. Methods: Sixteen participants with chronic stroke and nine age-matched controls performed three trials of functional reach-to-grasp. The amount of variability was quantified by computing the standard deviation of shoulder, elbow, wrist and index finger flexion/extension joint angles. The temporal structure of variability was determined by calculating approximate entropy in shoulder, elbow, wrist and index finger flexion/extension joint angles. Findings: Individuals with stroke demonstrated greater standard deviations and significantly reduced approximate entropy values as compared to controls. Furthermore, motor impairments and kinematics demonstrated moderate to strong correlations with temporal structure of variability. Interpretation: Changes in the temporal structure of variability in upper-extremity joint angles suggest that movement patterns used by stroke survivors are less adaptable. This knowledge may yield additional insights into the impaired motor system and suggest better interventions that can enhance upper-extremity movement adaptability.
Contralesional Hemisphere Control of the Proximal Paretic Upper Limb following Stroke
Cerebral Cortex, 2012
Cathodal transcranial direct current stimulation (c-tDCS) can reduce excitability of neurons in primary motor cortex (M1) and may facilitate motor recovery after stroke. However, little is known about the neurophysiological effects of tDCS on proximal upper limb function. We hypothesized that suppression of contralesional M1 (cM1) excitability would produce neurophysiological effects that depended on the severity of upper limb impairment. Twelve patients with varying upper limb impairment after subcortical stroke were assessed on clinical scales of upper limb spasticity, impairment, and function. Magnetic resonance imaging was used to determine lesion size and fractional anisotropy (FA) within the posterior limbs of the internal capsules indicative of corticospinal tract integrity. Excitability within paretic M1 biceps brachii representation was determined from motor-evoked potentials during selective isometric tasks, after cM1 sham stimulation and after c-tDCS. These neurophysiological data indicate that c-tDCS improved selective proximal upper limb control for mildly impaired patients and worsened it for moderate to severely impaired patients. The direction of the neurophysiological after effects of c-tDCS was strongly related to upper limb spasticity, impairment, function, and FA asymmetry between the posterior limbs of the internal capsules. These results indicate systematic variation of cM1 for proximal upper limb control after stroke and that suppression of cM1 excitability is not a ''one size fits all'' approach.