Changing a reflex to improve locomotion

改变反射以改善运动

• 批准号: 8256776
• 负责人: Aiko Thompson
• 金额: $ 29.23万
• 依托单位: HELEN HAYES HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2015-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8256776
• 关键词: Accounting; Acute; Affect; Aftercare; Ankle; Behavior; Chronic; Complement; Conditioned Reflex; Data; Development; Gait; Goals; H-Reflex; Health; Human; Hyperreflexia; Individual; Injury; Learning; Life; Locomotion; Lower Extremity; Methods; Modification; Monkeys; Motor; Movement; Muscle; Natural regeneration; Neuraxis; Operant Conditioning; Pathway interactions; Pattern; Phase; Population; Procedures; Protocols documentation; Rattus; Recovery; Recovery of Function; Reflex action; Rehabilitation therapy; Shapes; Skeletal Muscle; Spastic; Spastic Gait; Speed; Spinal; Spinal cord injury; Techniques; Testing; Therapeutic Effect; Walking; Work; abnormal reflex; analog; animal data; base; conditioning; conventional therapy; disability; human data; human subject; improved; kinematics; novel therapeutic intervention; restoration; spinal reflex; stretch reflex

DESCRIPTION (provided by applicant): People with incomplete spinal cord injury (SCI) often have substantial disabilities, even after completing conventional therapy. Common motor abnormalities after SCI include spasticity and weak voluntary muscle control. Altered spinal reflex pathways contribute to these problems. In this population, exaggerated stretch reflex and abnormal reflex modification of the ankle extensors are frequently observed. Normally, spinal reflexes are modulated from standing to walking, and during walking reflexes are further modulated between different phases of the gait cycle. However, in individuals after SCI, modulation of the soleus H-reflex during walking is often absent or greatly diminished (i.e., the reflex amplitude remains high even in the early stance or swing phase, where the H-reflex is normally very small or absent). Spinal reflexes can be changed through operant conditioning. Previous work in rats and monkeys shows that successful operant conditioning of a spinal reflex changes not only the reflex pathway that is conditioned but also the activity of other spinal and supraspinal pathways. Therefore, it may be possible to guide central nervous system plasticity associated with learning to change the activity of a spinal reflex pathway such that movement disabilities can be ameliorated. The goal of this project is to investigate the impact of changing a spinal reflex on impaired locomotion after chronic incomplete SCI in people. In humans, reflex conditioning with a far smaller number of trials per day than those used in rats can produce a comparable amount of reflex change. Recent work in rats shows that soleus H-reflex operant conditioning changes soleus behavior during locomotion, and indicates that appropriate conditioning can improve locomotion after incomplete SCI. Based on these findings, this project will test two hypotheses. The first hypothesis is that, in subjects with spastic hyperreflexia due to chronic incomplete SCI, decreasing the soleus H-reflex by operant down-conditioning can improve locomotion. The second hypothesis is that, locomotion can be further improved by applying down-conditioning procedures during appropriate phases of locomotion, when the H-reflex should normally be absent. These hypotheses will be tested by applying down-conditioning of the soleus H-reflex in spastic subjects with incomplete SCI. The impact of conditioning on the locomotor EMG activity, reflex modulation during gait, gait kinematics, and walking speed will be assessed, before and after conditioning. We will also assess the persistence of these effects. We expect to find that successful H-reflex down-conditioning can improve locomotion recovery after incomplete SCI and that this improvement will persist. Successful completion of this project will facilitate development of spinal reflex operant conditioning as a new, therapeutic approach to improving motor function recovery for individuals after SCI. This new method should complement existing methods and augment restoration of useful function. PUBLIC HEALTH RELEVANCE: With recent advances in acute care after spinal cord injury (SCI), which has resulted in more cases of incomplete SCI, and development of regeneration therapies, rehabilitation for functional recovery is becoming increasingly important for re-establishing an active, productive, fulfilling life in these individuals. In order to maximize functional recovery after SCI, it is extremely important to continue developing new therapeutic approaches beyond conventional rehabilitation techniques. The goal of this project is to investigate the therapeutic effects of changing a spinal reflex on impaired locomotion after chronic incomplete SCI. Successful completion of this project will open up a new therapeutic approach for treating individuals after SCI.

描述（由申请人提供）：即使完成常规疗法，脊髓损伤不完全的人（SCI）也经常有实质性的残疾。 SCI后的常见运动异常包括痉挛和自愿性肌肉弱。脊柱反射途径改变会导致这些问题。在这个人群中，经常观察到脚踝伸肌的夸张拉伸反射和异常反射修饰。通常，脊柱反射是从站立到步行的调节，在步行过程中，在步态循环的不同阶段之间进行了进一步调节。但是，在SCI后的个体中，步行过程中比目鱼的调节通常不存在或大大减少（即，即使在早期的姿势或挥杆阶段，H-Reflex通常很小或不存在）。 可以通过操作调节更改脊柱反射。先前在大鼠和猴子中的工作表明，脊柱反射的成功操作调节不仅会改变条件的反射途径，而且会改变其他脊柱和上脊柱上途径的活性。因此，有可能指导中枢神经系统可塑性与学习改变脊柱反射途径的活性相关，从而可以改善运动障碍。该项目的目的是调查改变脊柱反射对人类慢性不完整SCI后运动受损的影响。 在人类中，每天试验数量要小得多的反射调节能够产生可比的反射变化。大鼠的最新工作表明，比目鱼H-反射操作方调节在运动过程中会改变比目鱼的行为，并表明适当的条件可以改善不完整的SCI后的运动。基于这些发现，该项目将检验两个假设。第一个假设是，在由于慢性不完整的SCI引起的痉挛性超反射症的受试者中，通过操作下的下调降低了比目鱼H反射，可以改善运动。第二个假设是，在通常不存在H反射时，可以通过在适当的运动阶段应用下调程序来进一步改善运动。 这些假设将通过在不完整的SCI的痉挛性受试者中施加soleus h反射的下调来检验。调节对运动的影响，步态运动学期间的反射调制，步态运动学和步行速度的影响将在调节前后进行评估。我们还将评估这些影响的持久性。我们希望发现成功的H反射下调可以改善SCI不完整后的运动恢复，并且这种改进将持续存在。该项目的成功完成将有助于开发脊柱反射操作条件，作为一种新的治疗方法，可改善SCI之后的个体运动功能恢复。这种新方法应补充现有方法并增加有用功能的恢复。 公共卫生相关性：随着脊髓损伤后急性护理的最新进展（SCI），导致了更多的SCI病例，并开发了再生疗法，功能恢复的康复对于重建这些人的积极，生产力，实现的生活变得越来越重要。为了在SCI之后最大化功能恢复，继续开发新的治疗方法以外的传统康复技术非常重要。该项目的目的是研究慢性不完整SCI后改变脊柱反射对运动受损受损的治疗作用。该项目的成功完成将开辟一种新的治疗方法，以治疗科学后的个人。