Principles Of Neuroplasticity Research Articles

SIG 2 Perspectives Vol. 21, No. 3, October 2011

SIG 2 Perspectives Vol. 21, No. 3, October 2011

The Emerging Role of Cognitive Remediation Therapy

Age-related cognitive declines can hinder older adults' ability to perform instrumental activities of daily living. As a result, this decline places an additional burden on formal and informal caregivers. Fortunately, based on the principles of cognitive reserve and neuroplasticity, cognitive remediation therapy shows promise in reducing the severity of such cognitive declines and improving everyday functioning. Incorporating such therapy into institutional settings represents an avenue for improving cognitive functioning, ameliorating self-care, and facilitating successful aging. Suggestions for adapting this approach in institutional settings are provided.

Functional Outcomes Can Vary by Dose: Learning-Based Sensorimotor Training for Patients Stable Poststroke

Objective. This study aimed to determine whether the dose of learning-based sensorimotor training (LBSMT) significantly enhances gains in upper limb function in patients stable post stroke. Methods. A total of 45 subjects stable poststroke participated in a 6-8-week LBSMT program of varied dosage: group I (n = 18; 1×/week, 1.5 hours/visit); group II (n = 19, 3×/week, 0.75 hours/visit); and group III (n = 8; 4×/week, 3 hours/visit). All subjects reinforced their training with home-based practice. The primary outcome measures were functional independence, strength, sensory discrimination, and fine motor skills. Results. Across all individual subjects, significant gains were measured on the 4 dependent variables (improvement ranging from 9.0% to 38.9%; P < .001). Group III made greater gains than groups I and II on functional independence, sensory discrimination, and fine motor skills, with a significant linear trend by dose for functional independence (P < .001). Only 2-3 subjects in groups I and II, respectively, would need to be treated at the high dosage of group III for one more subject to achieve >50% gain in functional independence. Conclusions. Learning-based sensorimotor training based on the principles of neuroplasticity was associated with improved function in patients stable poststroke. The gains were dose specific with the greatest change measured in subjects participating in the high-intensity treatment group.

Neuroplasticity and Rehabilitation Research for Speech, Language, and Swallowing Disorders

This article introduces a collection of consensus statements regarding the application of neuroplasticity principles to rehabilitation of dysphagia, dysarthria, apraxia, and aphasia.

Aberrant learning in individuals who perform repetitive skilled hand movements: Focal hand dystonia—Part 1

Summary Stressful, repetitive use of the upper limb in work, sports, or musical performance can lead to acute, pain and loss of function. The evidence for tissue mircrotrauma as the underpinnings of this pain is convincing and explains why rest, anti-inflammatory medications, change in movement biomechanics and good ergonomics are usually effective treatment modalities. Unfortunately, some repetitive strain injuries become chronic with degenerative changes found in tendons and muscles, scarring restricting soft tissue and joint mobility and compression of peripheral nerves causing strain and limiting excursion. In other cases, involuntary co-contractions of flexors and extensors lead to painless, uncontrollable, end range twisting movements that interfere with the performance of target tasks. This movement dysfunction is referred to as occupational hand cramps, focal hand dystonia (FHd), golfers yip, keyboarders cramps, or musician's cramps. Research studies report evidence of degradation of the somatosensory, sensorimotor and motor representation of the hand in animals and patients with dystonic hand movements. This aberrant learning requires learning based training to reorganize the brain. In this presentation, the principles of neuroplasticity will be related to the origin, diagnosis, assessment and treatment of FHd grounded on an evidence-based review of the research to support aberrant learning as one etiology for the origin of this disorder and the foundation for a learning based approach to remediate the condition.

Effect of sensory discrimination training on structure and function in patients with focal hand dystonia: a case series

Byl NN, Nagajaran S, McKenzie AL. Effect of sensory discrimination training on structure and function in patients with focal hand dystonia: a case series. Arch Phys Med Rehabil 2003;84:1505–14. Objective To measure the effects of sensorimotor training based on the principles of neuroplasticity for patients with focal hand dystonia. Design Case series of 3 subjects with focal hand dystonia of the left hand, compared with age-matched normative controls. Setting Outpatient clinic. Participants Three consecutive clinic patients—musicians with focal hand dystonia—who described a history of repetitive practice and performance (2 women; ages, 23y and 35y; 1 man; age, 24y). Intervention Subjects were asked to stop performing the tasks that caused the abnormal movements, to participate in a wellness program (aerobics, postural exercises, stress free hand use), and to carry out supervised, attended, individualized, repetitive sensorimotor training activities at least once week for 12 weeks and reinforced daily at home. Main outcome measures Standard tests documenting somatosensory hand representation, target-specific hand control, and clinical function. Results On the affected side, the 3 subjects improved an average of 86.8% on somatosensory hand representation, 117% on target-specific performance, 23.9% on fine motor skills, 22.7% on sensory discrimination, 31.9% on musculoskeletal skills, and 32.3% on independence. All 3 subjects improved 10% or more on 90% of the subtests with 20% improvement on 50% of the subtests. Conclusion Individuals with focal hand dystonia who have a history of repetitive hand use can improve cortical somatosensory responses and clinical motor function after individualized sensorimotor training consistent with the principles of neural adaptation.

Correlation of Clinical Neuromusculoskeletal and Central Somatosensory Performance: Variability in Controls and Patients With Severe and Mild Focal Hand Dystonia

Focal hand dystonia (FHd) is a recalcitrant, disabling movement disorder, characterized by involuntary co-contractions of agonists and antagonists, that can develop in patients who overuse or misuse their hands. The aim of this study was to document clinical neuromusculoskeletal performance and somatosensory responses (magnetoencephalography) in healthy controls and in FHd subjects with mild versus severe hand dystonia. The performance of healthy subjects (n = 17) was significantly better than that of FHd subjects (n = 17) on all clinical parameters. Those with mild dystonia (n = 10) demonstrated better musculoskeletal skills, task-specific motor performance, and sensory discrimination, but the performance of sensory and fine motor tasks was slower than that of patients with severe dystonia. In terms of somatosensory evoked field responses (SEFs), FHd subjects demonstrated a significant difference in the location of the hand representation on the x and y axes, lower amplitude of SEFs integrated across latency, and a higher ratio of mean SEF amplitude to latency than the controls. Bilaterally,. those with FHd (mild and severe) lacked progressive sequencing of the digits from inferior to superior. On the affected digits, subjects with severe dystonia had a significantly higher ratio of SEF amplitude to latency and a significantly smaller mean volume of the cortical hand representation than those with mild dystonia. Severity of dystonia positively correlated with the ratio of SEF mean amplitude to latency (0.9029 affected, 0.8477 unaffected; p<0.01). The results of the present study strengthen the evidence that patients with FHd demonstrate signs of somatosensory degradation of the hand that correlates with clinical sensorimotor dysfunction, with characteristics of the dedifferentiation varying by the severity of hand dystonia. If these findings represent aberrant learning, then effective rehabilitation must incorporate the principles of neuroplasticity. Training must be individualized to each patient to rebalance the sensorimotor feedback loop and to restore normal fine motor control.