Characterization of Physiological Changes Induced Through MEP Conditioning in People with SCI

SCI 患者通过 MEP 调理引起的生理变化的特征

• 批准号: 10318182
• 负责人: Aiko Thompson
• 金额: $ 32.48万
• 依托单位: MEDICAL UNIVERSITY OF SOUTH CAROLINA
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-12-01 至 2024-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10318182
• 关键词: Ankle; Bilateral; Chronic; Complement; Cutaneous; Data; Development; Disease; Exposure to; Financial compensation; Foot-drop; Gait; H-Reflex; Hip region structure; Impairment; Individual; Injury; Intervention; Joints; Knee; Leg; Life; Location; Locomotion; Maps; Measurement; Measures; Mediation; Motion; Motor Evoked Potentials; Muscle; Nature; Neuronal Plasticity; Operant Conditioning; Orthotic Devices; Participant; Pathway interactions; Persons; Phase; Physical therapy; Physiological; Population; Process; Protocols documentation; Recovery; Recovery of Function; Reflex action; Rehabilitation therapy; Shapes; Site; Spinal cord injury; Stimulus; Testing; Time; Transcranial magnetic stimulation; Walking; ankle joint; ankle joint dorsiflexor; base; clinical translation; common treatment; conditioning; cortex mapping; equilibrium model; foot; improved; improved outcome; kinematics; motor control; motor function improvement; motor impairment; motor recovery; neurological rehabilitation; neuromechanism; neuroregulation; novel; recruit; response; spinal reflex; standard care; tibialis anterior muscle; tool

Project Summary / Abstract Spinal cord injury (SCI) often disrupts corticospinal drive, resulting in weak voluntary activation of muscles and impaired motor control. Thus, an intervention that further improves corticospinal function could enhance motor recovery. However, such neuromodulatory interventions are not currently available to people with incomplete SCI. For example, other than conventional physical therapy, the most common treatment for foot drop (weak ankle dorsiflexion), which often impairs gait in this population, is an ankle foot orthosis. These standard treatments do not aim to restore corticospinal drive and may even depress it further. Operant conditioning of a stimulus-triggered EMG response, which can target beneficial plasticity to the pathway that produces the response may be able to fill this gap. The overarching hypothesis of this project is that increasing the size of the motor evoked potential (MEP) elicited by transcranial magnetic stimulation through operant conditioning can improve corticospinal activation of the targeted muscle and thereby improve motor function in which that muscle participates. In people with incomplete SCI, the tibialis anterior (TA) MEP is often small, reflecting reduced corticospinal excitability. This weakened corticospinal activation of TA contributes to foot drop, which further impairs their gait through a chain of compensation and maladaptation at knee and hip. Thus, a therapy that increases corticospinal excitability for TA may reduce foot drop and other associated problems, and thereby improve walking. Recent small studies of TA MEP conditioning suggest that MEP up-conditioning can increase the corticospinal excitability for TA and can improve gait in people with chronic SCI. Building upon those initial findings, this project seeks to characterize the physiological mechanisms and effects of TA MEP conditioning. Individuals with weak dorsiflexion due to chronic incomplete SCI are exposed to 42 1-hr MEP sessions (6 baseline followed by 36 up-conditioning or 36 control sessions). Before baseline and after 12, 24, 36 conditioning (or control) sessions, (1) to characterize the cortical and corticospinal mechanisms of the TA MEP changes produced by MEP up-conditioning, cortical MEP map, MEP recruitment curve, short-interval cortical inhibition, cervicomedullary MEP, H-reflex, and F-wave are measured; and (2) to characterize the impact of TA MEP up- conditioning on locomotor function, bilateral locomotor EMG and kinematics measurements, 10-m and 6-min walking tests, and locomotor reflex testing are performed. Determining how MEP conditioning induces cortical and corticospinal plasticity and how such plasticity changes locomotion in people with incomplete SCI will illuminate the dynamic process of inducing and shaping functionally-relevant CNS multi-site plasticity through guiding targeted plasticity. The results will help to navigate development and clinical translation of MEP operant conditioning, as a novel non-invasive therapy that may complement other therapies and further enhance recovery in people with SCI or other disorders.

项目摘要 /摘要 脊髓损伤（SCI）经常破坏皮质脊髓驱动，导致肌肉的自愿激活弱 电机控制受损。因此，一种进一步改善皮质脊髓功能的干预措施可以增强运动 恢复。但是，这种神经调节干预措施目前尚不适合患有不完整的人 科学。例如，除了常规的物理疗法以外，脚滴最常见的治疗方法（弱 脚踝背屈）是脚踝矫形器，通常会损害该人群中的步态。这些标准 治疗的目的不是恢复皮质脊髓驱动，甚至可能进一步抑制它。操作条件 刺激触发的EMG响应，可以将有益的可塑性靶向产生的途径 响应可能能够填补这一空白。该项目的总体假设是增加 通过操作引起的转经磁刺激引起的电动机诱发电势（MEP） 调节可以改善靶向肌肉的皮质脊髓激活，从而改善电动机 肌肉参与的功能。 在SCI不完整的人中，胫骨前（TA）MEP通常很小，反映了皮质脊髓的减少 兴奋性。这种弱的TA皮质脊髓激活有助于脚下，这进一步损害了他们的步态 通过膝盖和臀部的一系列补偿和不适。因此，一种增加皮质脊髓的疗法 TA的兴奋性可能会减少脚部下降和其他相关问题，从而改善步行。最近的 TA MEP调节的小型研究表明，MEP上的调节可以增加皮质脊髓 TA的兴奋性并可以改善患有慢性SCI的人的步态。在这些初步发现的基础上，这个项目 试图表征TA MEP调节的生理机制和影响。 由于慢性不完整SCI引起的背屈弱的个体暴露于42个1小时MEP会议（6个 基线，然后进行36个上调节或36个控制课程）。基线之前和12、24、36条调理 （或对照）会话，（1）表征TA MEP的皮质和皮质脊髓机理 由MEP上调，皮质MEP图，MEP募集曲线，短间隔皮质抑制作用，生产 测量子宫颈MEP，H反射和F波； （2）表征ta mep up的影响 - 对运动功能，双侧运动EMG和运动学测量的调节，10米和6分钟 进行步行测试和运动反射测试。 确定MEP调节如何诱导皮质和皮质脊髓可塑性以及这种可塑性如何变化 SCI不完整的人的运动将阐明诱导和塑造的动态过程 通过引导靶向可塑性，在功能上与功能相关的CNS多站点可塑性。结果将有助于导航 MEP操作调节的开发和临床翻译是一种新型的非侵入性疗法，可能 补充其他疗法，并进一步增强SCI或其他疾病患者的康复。