Sensory contributions to typical and atypical development of trunk control

描述(申请人提供)：运动控制的主要挑战之一是了解中枢神经系统如何控制身体的自由度。这在脑性瘫痪(CP)中尤为明显，这是最普遍的慢性儿童运动障碍，也是儿童和成人最致残和代价最高的慢性疾病之一。姿势控制和感觉运动整合缺陷是脑性瘫痪的特征。尽管有目前的治疗方法，33%的CP儿童从未达到稳定的坐姿平衡。尽管独立坐着时对躯干的姿势控制为所有其他 运动任务，令人惊讶的是，关于婴儿如何利用感觉输入来指导他们直立控制的发展(通常发生在8个月大时)，人们知之甚少。这种知识的缺乏限制了我们有效评估和治疗躯干控制神经运动缺陷儿童的能力。目标1将在一项纵向研究中确定感觉依赖和感觉重新加权 在发育稳定的坐姿(1-8个月大)之前和期间，典型发育的(TD)婴儿。目的2将在一项对中到重度脑性瘫痪(4-12岁)儿童的横断面研究中确定感觉依赖和感觉重塑。一种新的躯干支撑装置将能够对缺乏(或仍在发展)稳定坐姿的参与者进行测试。在实验中，将测量头部和躯干的运动学。感觉依赖和重新加权将从躯干对感觉冲突刺激的体位反应中识别出来，这些刺激包括视觉周围的倾斜和/或参与者坐着的表面的倾斜。一般来说，参与者具有高的 在所有测试中，对前庭反馈的依赖将保持相对于重力的直立；而高度依赖皮肤或视觉反馈将分别产生躯干偏离直立和朝向表面或视觉周围倾斜。为了梳理出生物力学、物理和神经对躯干摇摆的影响，将使用感觉运动集成建模来补充数据解释。从这项研究中获得的知识将使临床医生能够开发新的评估和干预方法，并可能导致为中到重度脑瘫儿童创造新的支持设备。在典型发育过程中识别感觉运动整合将提供基准，以与影响躯干控制的其他各种神经或肌肉骨骼缺陷进行比较，包括CP.预计，除了识别感觉依赖之外，收集的丰富数据集和量化模型开发将深入了解感觉运动噪声、变异性、系统线性和内部模型的问题，生成试点数据并为未来的R01拨款完善假设。

DESCRIPTION (provided by applicant): One of the major challenges of motor control is to understand how the central nervous system controls the degrees of freedom of the body. This is particularly evident in cerebral palsy (CP), which is the most prevalent chronic childhood motor disability and is one of the most disabling and costly chronic disorders of children and adults. Deficits in postural control and sensorimotor integration are hallmarks of CP. Thirty-three percent of children with CP never achieve stable sitting balance in spite of current treatments. Although postural control of the trunk for independent sitting creates the foundation for all other motor tasks, surprisingly little is known about how infants use sensory input to guide their development of upright control (which typically occurs by 8 months of age). This lack of knowledge limits our ability to effectively assess and treat children with neuromotor deficits in trunk control. AIM 1 will identify sensory reliance and sensory reweighting in a longitudinal study of typically developing (TD) infants prior to, and during, development of stable sitting (1-8 months of age). AIM 2 will identify sensory reliance and sensory reweighting in a cross sectional study of children with moderate-to-severe CP (4-12 yrs of age). A novel trunk support device will enable testing of participants who lack (or are still developing) stable sitting. In experiments, kinematics of the head and trunk will be measured. Sensory reliance and reweighting will be identified from postural trunk responses to sensory conflict stimuli consisting of tilts of a visua surround and/or tilts of a surface which participants sit upon. Generally, participants with a high reliance on vestibular feedback will remain upright with respect to gravity during all tests; whereas a high reliance on cutaneous or visual feedback will produce trunk sway away from upright and toward the surface or visual surround tilt, respectively. To tease apart biomechanical, physical, and neurological contributions to trunk sway, sensorimotor integration modeling will be used to complement data interpretation. Knowledge obtained from this study will allow clinicians to develop new methods of assessment and intervention and may lead to creation of novel support devices for children with moderate-to-severe CP. The identification of sensorimotor integration during typical development will provide benchmarks for comparison with a variety of other neural or musculoskeletal deficits that affect trunk control, including CP.It is anticipated that, in addition to identification of sensory reliance, the rich data set collectedand quantitative model development will give insight into questions about sensorimotor noise, variability, system linearity, and internal models, generating pilot data and refining hypotheses for future R01 grants.