Effects of Parkinson's disease on proprioceptive control of posture and reaching while standing (original) (raw)
Related papers
Proprioception and Motor Control in Parkinson's Disease
Journal of Motor Behavior, 2009
Parkinson's disease (PD) is a neurodegenerative disorder that leads to a progressive decline in motor function. Growing evidence indicates that PD patients also experience an array of sensory problems that negatively impact motor function. This is especially true for proprioceptive deficits, which profoundly degrade motor performance. This review specifically address the relation between proprioception and motor impairments in PD. It is structured around 4 themes: (a) It examines whether the sensitivity of kinaesthetic perception, which is based on proprioceptive inputs, is actually altered in PD. (b) It discusses whether failed processes of proprioceptive-motor integration are central to the motor problems in PD. (c) It presents recent findings focusing on the link between the proprioception and the balance problems in PD. And (d) it discusses the current state of knowledge of how levodopa medication and deep brain stimulation affect proprioceptive and motor function in PD. The authors conclude that a failure to evaluate and to map proprioceptive information onto voluntary and reflexive motor commands is an integral part of the observed motor symptoms in PD.
Neuroscience, 2006
Subjects with Parkinson's disease exhibit abnormally short compensatory steps in response to external postural perturbations. We examined whether: (1) Parkinson's disease subjects exhibit short compensatory steps due to abnormal central proprioceptive-motor integration, (2) this proprioceptive-motor deficit can be overcome by visual-motor neural circuits using visual targets, (3) the proprioceptivemotor deficit relates to the severity of Parkinson's disease, and (4) the dysfunction of central dopaminergic circuits contributes to the Parkinson's disease subjects' proprioceptivemotor deficit. Ten Parkinson's disease subjects and 10 matched control subjects performed compensatory steps in response to backward surface translations in five conditions: with eyes closed, with eyes open, to a remembered visual target, to a target without seeing their legs, and to a target while seeing their legs. Parkinson's disease subjects were separated into a moderate group and a severe group based on scores from the Unified Parkinson's Disease Rating Scale and were tested off and on their dopamine medication. Parkinson's disease subjects exhibited shorter compensatory steps than did the control subjects, but all subjects increased their step length when stepping to targets. Compared with the other subject groups, the severe Parkinson's disease subjects made larger accuracy errors when stepping to targets, and the severe Parkinson's disease subjects' step accuracy worsened the most when they were unable to see their legs. Thus, Parkinson's disease subjects exhibited short compensatory steps due to abnormal proprioceptive-motor integration and used visual input to take longer compensatory steps when a target was provided. In severe Parkinson's disease subjects, however, visual input does not fully compensate because, even with a target and unobstructed vision, they still exhibited poor step accuracy. Medication did not consistently improve the length and accuracy of the Parkinson's disease subjects' compensatory steps, suggesting that degeneration of dopamine circuits within the basal ganglia is not responsible for the proprioceptive-motor deficit that de-grades compensatory steps in Parkinson's disease subjects. (J. V. Jacobs).
Parkinson's disease does not alter automatic visual-motor coupling in postural control
Neuroscience letters, 2018
This study examined the coupling between visual information and body sway in patients with Parkinson's disease (PD) compared with healthy controls. Postural control performance was compared between 14 patients with PD (age: 69.6 ± 8.8 years - stages 1-3 of the Hoehn and Yahr scale) and 14 healthy control participants (age: 68.6 ± 3.0 years). Participants stood upright in a moving room that remained motionless or continuously oscillated in the anterior-posterior direction. Ten trials were performed in the following conditions: no movement of the room (1 trial) and with the room moving at frequencies of 0.1, 0.17, and 0.5 Hz (3 trials each frequency). Body sway and moving room displacement were recorded. The results indicated that patients with PD displayed larger body sway magnitude in the stationary room condition. Body sway of patients with PD was induced by visual manipulation in all three visual stimulus frequencies, but body sway of patients with PD was less coherent compare...
Visual control of arm movement in Parkinson's disease
Movement Disorders, 1994
Patients with Parkinson's disease (PD) are more dependent on visual information during movements than normals. To investigate the mechanisms underlying deterioration of movement under nonvisual conditions, we studied two-dimensional pointing movements to randomly occurring targets. The experimental design allowed us to systematically manipulate visual feedback during the movement by removing vision of the target, of the moving hand, or of both. Execution of pointing movements in PD deviated most severely from that of normals when PD patients moved without vision of their own moving hand. Under this condition, undershooting of the target appeared, and movements were particularly slow. In contrast, with complete vision or when only vision of the target was occluded, pointing movements of PD patients were accurate and faster. PD patients had no difficulties selecting the correct movement direction. Reaction times were longer in PD patients irrespective of the availability of visual feedback. Our findings suggest that the ability of PD patients to use nonvisual feedback during execution of arm movements is impaired.
New insight into Parkinson’s disease‐related impairment of the automatic control of upright stance
European Journal of Neuroscience, 2020
Parkinson's disease (PD) affects the automatic control of body movements. In our study, we tested PD-related impairments in automatic postural control in quiet upright stance. Twenty PD patients (mean age: 60 ± 8 years; Hoehn and Yahr: 2.00 ± 0.32, on-drug) and twenty age-matched controls (61 ± 7 years) were recruited. We studied interrelations between center-of-pressure movements, body movements (head, neck, and lower back), eye movements and variability of pupil size. Participants performed two fixation tasks while standing, during which they looked at: (a) a cross surrounded by a white background; and (b) a cross surrounded by a structured visual background (images used: rooms in houses). PD patients exhibited stronger and weaker correlations between eye and center-of-pressure/body movement variables than age-matched controls in the white and structured fixation tasks, respectively. Partial correlations, controlling for variability of pupil size showed that PD patients used lower and greater attentional resources than age-matched controls to control their eye and center-of-pressure/body movements simultaneously in the white fixation and structured fixation tasks, respectively. In the white fixation task, PD patients used attentional resources to optimize visuomotor coupling between eye and body movements to control their posture. In the structured fixation task, the salient visual stimuli distracted PD patients' attention and that possibly affected postural control by deteriorating the automatic visuomotor coupling. In contrast, age-matched controls were able to use surrounding visual background to improve the automatic coupling between eye and center-of-pressure movements to control their posture. These results suggest that cluttered environments may distract PD patients and deteriorate their postural control.
Experimental Brain Research, 2000
The role of the basal ganglia in the coordination of different body segments and utilization of motor synergies was investigated by analyzing reaching movements to remembered three-dimensional (3D) targets in patients with Parkinson's disease (PD). Arm movements were produced alone or in combination with a forward bending of the trunk, with or without visual feedback. Movements in PD patients were more temporally segmented, as evidenced by irregular changes in tangential velocity profiles. In addition, the relative timing in the onsets and offsets of fingertip and trunk motions were substantially different in PD patients than in control subjects. While the control subjects synchronized both onsets and offsets, the PD patients had large mean intervals between the onsets and offsets of the fingertip and trunk motions. Moreover, PD patients showed substantially larger trial-to-trial variability in these intervals. The degree of synchronization in PD patients gradually increased during the movement under the influence of visual feedback. The mean and variability of the intersegmental intervals decreased as the fingertip approached the target. This improvement in timing occurred even though the separate variability in the timing of arm and trunk motions was not reduced by vision. In combined movements, even without vision, the PD patients were able to achieve normal accuracy, suggesting they were able to use the same movement synergies as normals to control the multiple degrees of freedom involved in the movements and to compensate for the added trunk movement. However, they were unable to recruit these synergies in the stereotyped manner characteristic of healthy subjects. These results suggest that the basal ganglia are involved in the temporal coordination of movement of different body segments and that related timing abnormalities may be partly compensated by vision. Abnormal intersegmental timing may be a highly sensitive indicator of a deficient ability to assemble complex movements in patients with basal-ganglia dysfunction. This abnormality may be apparent even when the overall movement goal of reaching a target is preserved and normal movement synergies appear to be largely intact.
Proprioceptive and Sensorimotor Performance in Parkinson's Disease
Research in Sports Medicine, 2006
We explored the effects of random whole-body-vibration on leg proprioception in Parkinson's disease. In earlier studies it was found that this treatment leads to improved postural control in these patients. Thus, one could speculate that these effects result from modified proprioceptive capabilities. Twenty-eight Parkinson's disease patients were subdivided in one experimental and one control group. Proprioceptive performance was analyzed using a tracking task basing on knee extension and flexion movements. Treatment consisted of 5 series of random whole-bodyvibration taking 60 seconds each. Control subjects had a rest period instead. Prominent over-and undershooting-errors were found in both groups representing proprioceptive impairments. However, no significant differences became evident neither between pre-and posttests nor between experimental and control group. One might therefore conclude that spontaneous improvements in postural control are not directly connected with proprioceptive changes. Nevertheless, one should also keep the mind on general aspects and difficulties of analyzing proprioception.
2003
This study investigated the effect of lengthening the time the hand remains immobilized on an aiming movement performed by Parkinson's disease (PD) patients and elderly adults, and whether visual information could compensate for the effects of delay. In Experiment One, PD patients and elderly adults kept the limb in a static position for 1, 6, or 10 s prior to movement initiation, both with and without vision of the initial limb position and the movement trajectory. Compared to elderly adults, PD patients had increased movement times and jerk scores, and exhibited shorter primary submovements that erred in initial movement direction. Lengthening the time delay increased movement time, decreased mean acceleration, and decreased the distance covered in the primary submovement for both groups. Parkinsonian patients, however, exhibited reduced length of the primary submovement across delay compared to elderly adults. Occluding vision caused the movements of PD patients to deteriorate on all measures. Although the performance of both groups was enhanced when vision was available, vision was not able to fully counteract the effects of delay in either group. In Experiment Two, participants moved to a previously viewed target to examine movement accuracy. Systematic undershooting of the target as a function of delay was found for both groups. Parkinsonian patients exhibited greater undershooting of the target after the primary submovement both with and without vision. Visual feedback reduced the effects of delay for both the elderly and PD patients. It can be inferred from the results that the decay in position sense as a function of time produces impairments in incorporating the initial limb position in motor planning process.
The effect of Parkinson’s disease on the control of multi-segmental coordination
Brain and Cognition, 2005
An experiment was designed to test whether or not Parkinson's disease (PD) patients were able to maintain endpoint kinematic patterns in a prehension task involving movement of the torso. Nine PD patients and nine healthy controls were asked to reach for and grasp a full cup of water that was either covered or uncovered and placed beyond the reach of the outstretched arm. An OPTOTRAK (Northern Digital) 3-dimensional motion analysis system was used to capture the movement of four markers placed on the arm, hand, and torso. The results indicated the Parkinson's patients had a decreased ability to maintain the kinematics of the end effector. The PD patients were also found to be impaired in terms of their ability to synchronize the arm, hand, and torso. More specifically, although the elderly controls seemed to employ a strategy of increasing the involvement of the torso when reaching to grasp the uncovered cup, no such strategy was observed in the PD patients. Collectively, the results suggest that the multi-joint synergies observed in the elderly controls, which help preserve relatively consistent endpoint trajectories, are disrupted in Parkinson's patients.