Sensory Re-education Improves Brain Plasticity in Stroke survivors

Background and Objective:Deficits in somatic sensations after stroke are common with prevalence rates variously reported to be 11% to 85%. Sensory impairments decrease the received feedback from the environment and consequently have negative impacts onthe function. These deficits in the upper extremity result inimpairments in the fine motor manipulation of objects, grasp and manipulative skills and in lower extremity has been related to poor standing balance, low gait speed and gait asymmetry. An increasing body of studies has suggested that adjunctive sensory re-education programshave significant impacts on sensory and motor recovery of the upper and lower extremityin stroke survivors, however the underlying mechanisms by which sensory re-education impacts the sensory-motor functions have not been well defined. The aim of this literature review was to provide an overview of important findings in this domain. Search Method: A comprehensive literature search on articles and book chapters was carried out. Seven bibliographic databases, three Iranian (SID, Iran Doc, Magiran) and four international (PubMed, Science Direct, Scopus, Cochrane), without time limitation, were searched. Multiple combinations of keywords (sensory re-education, sensory retraining and stroke) were used. Two researchers reviewed the title and abstracts independently. At the next stage, full texts were reviewed. Findings: Through three refining steps, 33 articles and books out of 130 records were found to be related to the present study.Conclusion:Sensory deficits of stroke survivors have received little attentionand the exact mechanism by which the sensory re-education improves the sensory and motor outcomes have not been studied and these mechanisms remains largely speculative. It has been proposed that somatosensory input, has the ability to drive plastic changes in the motor cortex and could modulate Use-Dependent Plasticity, restore cortical responsiveness and enhances excitability of the stimulated body part representation in the motor cortex and results in improvements in motor performance in stroke patients. It is generally believed that beneficial effects elicited by sensory stimulation are based on interconnections between somatosensory and motor cortex. These interconnections elicit a cortical reorganization in the primary motor cortex after stimulation, resulting in increased excitability of the motor cortical representations, in intracortical facilitation and in a decrease in intracortical inhibition, probably modulated byGABAergic neurotransmission.

کلیدواژه ها:

Sensory re-education ، Stroke ، Plasticity