Restorative Neurology and Neuroscience - Volume 22, issue 3-5

Authors: Celnik, Pablo A. | Cohen, Leonardo G.

Article Type: Research Article

Abstract: Basic science studies demonstrated mechanisms of plasticity and metaplasticity. More recent human studies identified some of these mechanisms as operating in multiple areas of human cognition, such as learning and memory, and in functional recovery from lesions in the CNS, as in stroke. One of the goals of neurorehabilitation is the translation of these principles into rational strategies to promote recovery of function. Understanding the mechanisms and functional role of human plasticity could lead to the …development of therapeutic options in situations in which there is virtually no treatment alternative, as in chronic stroke. We review some of the work performed to better understand the substrates and mechanisms underlying cortical plasticity and discuss some experimental approaches to enhance cortical plasticity and recovery of function, like cortical stimulation. Show more

Keywords: plasticity, motor, somatosensory, rehabilitation, TMS

Citation: Restorative Neurology and Neuroscience, vol. 22, no. 3-5, pp. 261-268, 2004

Authors: Liepert, J. | Hamzei, F. | Weiller, C.

Article Type: Research Article

Abstract: Introduction: A stroke may modulate motor cortex excitability. We examined if distinct ischemic brain lesions are associated with a specific pattern of excitability changes. We also investigated the effects of a rehabilitative therapy on motor excitability. Methods: In stroke patients, the consequences of a) a lesion in the central somatosensory system, b) a cerebellar lesion and c) a two week period of Constraint-induced movement therapy (CIMT), on motor cortex excitability were studied. Transcranial magnetic …stimulation techniques and functional magnetic resonance imaging (fMRI) were employed. Results: Patients with a lesion in the primary somatosensory cortex or in the ventroposterolateral nucleus of the thalamus had a decreased intracortical inhibition on the affected side. Patients with lesions in the territory of the superior cerebellar artery had a loss of intracortical facilitation and an increase of intracortical inhibition. Patients with cortical lesions undergoing CIMT had a loss of intracortical inhibition prior to therapy. After CIMT, changes of ICI were stronger in the lesioned than in the non-lesioned hemisphere but could result either in an increase of ICI or a reduction of ICI. In three patients fMRI results showed that cortical activation was less post CIMT as compared to pre-treatment activation. In parallel, ICI was reduced after treatment. Conclusions: Our results suggest that, physiologically, central somatosensory influence on the motor cortex is inhibitory. In contrast, the cerebellum normally exerts a facilitatory influence on the motor cortex. CIMT induces changes of intracortical excitability mainly in the affected hemisphere. Show more

Keywords: stroke, motor cortex excitability, Constraint-induced movement therapy, transcranial magnetic stimulation, functional magnetic resonance imaging

Citation: Restorative Neurology and Neuroscience, vol. 22, no. 3-5, pp. 269-277, 2004

Authors: Kwakkel, Gert | Kollen, Boudewijn | Lindeman, Eline

Article Type: Research Article

Abstract: Longitudinal studies show that almost all stroke patients experience at least some predictable degree of functional recovery in the first six months post stroke. However, the non-linear pattern as a function of time is not well understood. Several mechanisms are presumed to be involved, such as recovery of penumbral tissues, neural plasticity, resolution of diaschisis and behavioural compensation strategies. Rehabilitation is believed to modulate this logistic pattern of recovery, probably by interacting with these underlying processes. …However, prediction models that are adjusted for the effects of time after stroke onset suggest that outcome is largely defined within the first weeks post stroke, although functional improvement has been found to extend beyond six months post stroke. In addition, kinematic studies show that functional improvement is more than recovery from impairments alone, suggesting that patients are able to improve in terms of gait or dexterity deficits using behavioural compensation strategies. Therefore, understanding the impact of task-dependent cortical activation patterns in non-invasive methods requires not only information derived from longitudinal studies pertaining to functional outcomes, but also a better understanding of what is kinematically learned during the acquisition of new skills. Show more

Keywords: cerebrovascular disorders, recovery patterns, neural plasticity

Citation: Restorative Neurology and Neuroscience, vol. 22, no. 3-5, pp. 281-299, 2004

Authors: Platz, T.

Article Type: Research Article

Abstract: Everyday activities can be affected by many different body dysfunctions (impairments). A multi-modal analysis of electric brain activity revealed that movement-related brain activity is differentially altered in patients with different impairments, i.e. paresis, somatosensory deficits, and apraxia. Each body dysfunction has its own characteristics in terms of the resulting sensorimotor control deficits. The Impairment-oriented Training concept intends to characterise the resulting sensorimotor control deficits for each impairment. Based on such analyses two …specific training techniques have been developed for stroke patients with mild and severe arm paresis: (1.) The Arm Ability training for mild arm paresis trains different sensorimotor abilities such as dexterity, speed of isolated hand and finger movements, steadiness, aiming, or tracking under visual guidance. Improvement of these motor abilities leads to improved motor performance in every day life circumstances. (2.) The Arm BASI S training for severe arm paresis intends to restore more basic motor control, i.e. the full range of active non-segmented motion of all limb segments, both postural activities and dynamic motion control, interjoint-coordination, and adequate motor control when external forces are applied. Clinical trials with representative study populations supported both techniques' clinical efficacy. Show more

Keywords: stroke, arm, therapy, recovery, paresis, clinical trial, EEG

Citation: Restorative Neurology and Neuroscience, vol. 22, no. 3-5, pp. 301-315, 2004

Authors: Mark, Victor W. | Taub, Edward

Article Type: Research Article

Abstract: Constraint-Induced Movement Therapy (CI therapy) refers to a family of treatments for motor disability that combines constraint of movement, massed practice, and shaping of behavior to improve the amount of use of the targeted limb. CI therapy has controlled evidence for efficacy that supports its benefit for patients with chronic disability following central nervous system injury, regardless of their age or the interval since illness onset. Furthermore, the benefits transfer to real-world measures of limb use. …Significant functional improvement may occur even after the patient has been treated with conventional physical therapy. In this paper we review the evidence for the efficacy of CI therapy, particularly for chronic stroke hemiparesis, but also for diverse other chronic disabling illnesses, including non-motor disorders such as phantom limb pain and aphasia. The adaptation of the therapy to the stroke clinic is described, along with a review of the neurophysiologic mechanisms that are postulated to underlie the treatment benefit (overcoming learned nonuse, plastic brain reorganization). Critical to the success of CI therapy is its modification according to disease factors, economic considerations, limitations of the practice setting, and the cognitive and physical status of the patient. We conclude by recommending future areas for research on CI therapy. Show more

Keywords: stroke, hemiparesis, rehabilitation, aphasia, phantom limb pain, transcranial magnetic stimulation

Citation: Restorative Neurology and Neuroscience, vol. 22, no. 3-5, pp. 317-336, 2004

Authors: Cauraugh, James H.

Article Type: Research Article

Abstract: Identifying effective rehabilitation interventions founded on sound theoretical and neurophysiological bases should decrease the prevalence of motor disabilities and chronic hemiparesis. This article addresses two theoretically sound behavioral interventions: (a) active neuromuscular stimulation on the impaired upper extremity and (b) coupled bilateral coordination training (i.e., mirrored movements on the less impaired limb combined with active stimulation on the impaired limb). The series of stroke motor recovery experiments currently reviewed clearly indicate that …sensorimotor integration theory and bimanual coordination theory are viable candidates for directing behavioral rehabilitation approaches. Indeed, the reported evidence clearly supports activity dependent neural plasticity for progress toward stroke motor recovery. Show more

Keywords: stroke, chronic hemiparesis, upper extremity, motor recovery, coupled protocols, neural plasticity

Citation: Restorative Neurology and Neuroscience, vol. 22, no. 3-5, pp. 337-347, 2004

Authors: Hogan, Neville | Krebs, Hermano I.

Article Type: Research Article

Abstract: This article reviews a decade of work aimed at developing effective interactive robotic tools to treat and understand motor impairment and disability. The success of an initial pilot study with acute-phase in-patients recovering from stroke prompted a larger study showing that these results could be replicated and a follow-up study showing that the benefits lasted. Studies of chronic-phase out-patients demonstrated that similar benefits could be obtained which also lasted and were accompanied by a concomitant reduction …of pain. Exploration of the likely biology of recovery suggested an improvement of robotic treatment in the form of performance-based progressive therapy aimed at accelerating a process akin to motor learning postulated to underlie recovery. Initial studies of this method show a dramatic improvement over the previous successes. Kinematic studies of the recovery process show that, similar to the development of motor behavior in infants, it begins with stereotyped submovements and proceeds by progressively merging these to approach unimpaired motor performance. Show more

Keywords: robotics, rehabilitation, impairment, disability, stroke

Citation: Restorative Neurology and Neuroscience, vol. 22, no. 3-5, pp. 349-358, 2004

Authors: Hesse, S.

Article Type: Research Article

Abstract: The gait-lab at Klinik Berlin developed and evaluated novel physical and pharmacological strategies promoting the repetitive practise of hemiparetic gait in line with the slogan: who wants to relearn walking, has to walk. Areas of research are treadmill training with partial body weight support, enabling wheelchair-bound subjects to repetitively practice gait, the electromechanical gait trainer GT I reducing the effort on the therapists as compared to the manually assisted locomotor therapy, and the future …HapticWalker which will allow the additional practise of stair climbing up and down and of perturbations. Further means to promote gait practice after stroke was the application of botulinum toxin A for the treatment of lower limb spasticity and the early use of walking aids. New areas of research are also the study of D-Amphetamine, which failed to promote motor recovery in acute stroke patients as compared to placebo, and the development of a computerized arm trainer, Bi-Manu-T rack, for the bilateral treatment of patients with a severe upper limb paresis. Show more

Keywords: stroke, hemiparesis, treadmill, gait trainer, armtrainer, botulinum toxin

Citation: Restorative Neurology and Neuroscience, vol. 22, no. 3-5, pp. 359-369, 2004

Authors: Deutsch, Judith E. | Merians, Alma S. | Adamovich, Serge | Poizner, Howard | Burdea, Grigore C.

Article Type: Research Article

Abstract: Development and application of virtual reality (VR) systems for rehabilitation is an iterative process produced by collaboration of an inter-disciplinary team of engineers, neuroscientists and clinician-scientists. In this paper the use of virtual reality technology for the rehabilitation of individuals post-stroke is described. The development of the hardware is based on principles of motor control. Development of the software uses findings from the enrichment and motor plasticity and training literatures as well as …principles of motor learning. Virtual environments are created to afford individuals post-stroke opportunities to practice tasks for which they require rehabilitation. These tasks, related to hand function and gait, are trained both at the impairment and functional level. The training engages users to allow for the repetitive intensive practice required for behavioral motor plasticity. Results from a series of upper and lower extremity studies indicate that use of VR technology to augment rehabilitation of individuals post-stroke merits further study. Show more

Keywords: virtual reality, rehabilitation, motor learning, haptics

Citation: Restorative Neurology and Neuroscience, vol. 22, no. 3-5, pp. 371-386, 2004

Authors: Walker-Batson, D. | Smith, P. | Curtis, S. | Unwin, D.H.

Article Type: Research Article

Abstract: Over the past two decades, experimental studies following brain injury have shown that the central nervous system is dynamic and malleable to internal and external inputs. Neuromodulation and/or direct manipulation of motor and sensory experience can modify brain plasticity and functional outcome after experimental lesions. Specifically, pharmacologic modulation has been found to facilitate recovery of various behavioral deficits following occlusive injury. Additionally, the behavioral experience that induces long-term plasticity in motor and …sensory maps after injury appears to be limited to those that entail the development of new skills. These data have strong application to human rehabilitation. This review will: (1) overview critical experimental studies that show that pharmacologic manipulation and/or specific behavioral experience may modify the functional organization of the injured brain and (2) review beginning studies which are exploring the application of this knowledge clinically. Show more

Keywords: stroke, neuromodulation, pharmacotherapy, learning dependence, hemiplegia, aphasia

Citation: Restorative Neurology and Neuroscience, vol. 22, no. 3-5, pp. 387-392, 2004

Authors: Scheidtmann, Klaus

Article Type: Research Article

Abstract: Hemiparesis is common after stroke and often severely disabling. Until very recently, the only therapeutic option for motor recovery was physiotherapeutic training. Experimental animal studies have shown that when applied in addition to exercises pharmacological interventions that affect the norepinephrine system can enhance the rate of functional motor recovery. These effects were observed when an increase in norepinephrine concentration in the CNS was pharmacologically induced. We recently showed that 3 weeks of single …daily doses of 100 mg L-dopa, which is metabolized into norepinephrine in the brain, increase the efficacy of physiotherapy in hemiparetic stroke patients. Two additional randomized controlled trials with stroke patients also demonstrated the clinical relevance of this approach for motor recovery and independence in activities of daily living. Modifying effects of other frequently occurring clinical symptoms such as spasticity, neglect, and attention were also investigated. Thus, in view of its minimal side effects, L-dopa can be recommended in conjunction with exercise therapy to improve the functional outcome in stroke rehabilitation. Show more

Keywords: motor recovery, physiotherapy, L-dopa, stroke, noradrenaline

Citation: Restorative Neurology and Neuroscience, vol. 22, no. 3-5, pp. 393-398, 2004