Comparative Effects of Sensory Augmentation and Neuromodulation on Enhancing Motor Recovery Among Stroke Survivors

Overview

This study aims to evaluate the effectiveness of two rehabilitation techniques-Sensory Augmentation (using mirror therapy) and Neuromodulation (using transcranial direct current stimulation, tDCS)-in improving motor recovery among stroke survivors. Stroke often results in long-term impairments, particularly in upper limb motor function, which is critical for daily activities. Although current rehabilitation strategies help, more effective solutions are needed to enhance recovery. Participants, aged 45-65 with chronic stroke and upper extremity impairments, will be randomized into three groups: Group 1 will receive a combination of sensory augmentation (mirror therapy) and neuromodulation (tDCS) with routine physical therapy; Group 2 will receive sensory augmentation (mirror therapy) with routine physical therapy; and Group 3 will receive neuromodulation (tDCS) with routine physical therapy. The interventions will take place four times a week for 8 weeks, and participants will undergo motor function assessments, including the Fugl-Meyer Assessment and Jebsen-Taylor Test, before and after the intervention. The study will compare the effects of each intervention on motor recovery, specifically focusing on upper limb function and motor control. The findings could lead to improved rehabilitation protocols, offering stroke survivors better therapeutic options and enhancing their quality of life.

Stroke is one of the leading causes of disability worldwide, often leading to long-term impairments in motor function, particularly in the upper limbs. These impairments can severely affect a person's ability to perform daily tasks, reducing their independence and quality of life. The rehabilitation process for stroke survivors typically includes physical therapy aimed at improving motor control, balance, and functionality of the affected limbs. While traditional rehabilitation strategies are effective, there is a growing interest in enhancing recovery through advanced techniques such as Sensory Augmentation and Neuromodulation. This study will focus on evaluating the comparative effects of two innovative rehabilitation approaches-Sensory Augmentation through Mirror Therapy and Neuromodulation through Transcranial Direct Current Stimulation (tDCS)-on motor recovery in chronic stroke survivors. These two techniques have shown promising results in improving motor function in stroke patients, but their combined effect remains unclear. Intervention Strategies: Sensory Augmentation: Mirror therapy is a non-invasive technique that involves using a mirror to create the illusion of movement in the affected limb by reflecting the movement of the unaffected limb. This process enhances the sensory feedback and promotes neuroplasticity, which is the brain's ability to reorganize and form new neural connections. Mirror therapy has been shown to reduce spasticity, improve sensory functions like proprioception, and facilitate the restoration of motor function. Neuromodulation: Transcranial Direct Current Stimulation (tDCS) is a non-invasive brain stimulation technique that uses a low electrical current to modulate neuronal activity in specific areas of the brain. For stroke survivors, tDCS is applied to the motor cortex to promote neuroplasticity, facilitate the relearning of motor tasks, and reduce spasticity. While previous studies have demonstrated the effectiveness of tDCS, its impact when combined with sensory augmentation has not been fully explored. Study Design and Groups: This randomized controlled trial will involve 36 chronic stroke patients aged 45-65 who have upper extremity motor impairments. The participants will be randomly assigned to one of three groups: Group 1 (Experimental Group): A combination of sensory augmentation (mirror therapy) and neuromodulation (tDCS) along with routine physical therapy. Group 2: Sensory augmentation (mirror therapy) combined with routine physical therapy. Group 3: Neuromodulation (tDCS) combined with routine physical therapy. Each participant will undergo the interventions four times a week for 8 weeks. Routine physical therapy will include task-oriented training and reflex inhibitory patterns exercises aimed at improving motor control and coordination. Both sensory augmentation and neuromodulation will be administered for 30 minutes per session, with each intervention lasting 15 minutes for mirror therapy and 15 minutes for tDCS. The entire session, including physical therapy, will last for 45 minutes. Outcome Measures: The primary outcome of the study will be the improvement in upper limb motor function, measured by the Fugl-Meyer Assessment (FMA) for motor function and the Jebsen-Taylor Test, which assesses functional hand tasks. These assessments will be conducted before the intervention, at 4 weeks, and at 8 weeks to evaluate both short-term and long-term effects. Secondary outcomes will include improvements in the quality of life, as measured by validated scales like the Stroke Impact Scale (SIS), and the impact on daily activities, such as handgrip strength, motor coordination, and task performance. The effects on spasticity and sensory function will also be monitored. Data Collection and Analysis: Data will be collected at multiple time points during the study to assess the effects of the interventions on motor function, spasticity, and quality of life. Statistical analyses will include mixed-model ANOVA to examine the effects of time and intervention group on the primary and secondary outcomes. Post-intervention comparisons will be made to assess the differential impact of each intervention. Additionally, repeated measures ANOVA will be conducted to track within-group improvements over time. Safety and Ethics: This study has been approved by the institutional review board (IRB) of Lahore University of Biological and Applied Sciences, and all participants will provide informed consent before participating. To ensure the safety of participants, all sessions will be conducted under the supervision of trained physical therapists. Minimal risks associated with the study include mild discomfort or fatigue during the physical assessments and interventions. If any participant experiences adverse effects, they will be promptly withdrawn from the study. The study will also ensure the confidentiality of all participant data. Personal information will be anonymized, and data will be stored securely. Participation in the study is voluntary, and participants may withdraw at any time without facing any negative consequences. Significance and Potential Impact: This study has the potential to significantly impact stroke rehabilitation practices by providing evidence on the comparative efficacy of sensory augmentation and neuromodulation techniques in enhancing motor recovery. The results may guide clinicians in developing more effective rehabilitation protocols and inform future research on combined rehabilitation strategies. Given the growing incidence of stroke worldwide, particularly in low- and middle-income countries, this research could pave the way for accessible, cost-effective, and non-invasive therapeutic interventions. It may offer stroke survivors, especially those in resource-limited settings, improved chances for motor recovery and a better quality of life. Furthermore, this study will contribute valuable data to the scientific community, offering insights into the combined effects of mirror therapy and tDCS, which could enhance the evidence base for stroke rehabilitation. Conclusion: By comparing the effects of sensory augmentation and neuromodulation, this study aims to identify the most effective intervention(s) for improving motor recovery in stroke survivors. The findings will not only contribute to the field of neurorehabilitation but may also offer new therapeutic options for patients in need of effective, evidence-based treatments for motor impairments post-stroke.