Posture and Orientation in Older Adults and Post-Stroke

老年人和中风后的姿势和方向

• 批准号: 7101515
• 负责人: Emily A Keshner
• 金额: $ 33.16万
• 依托单位: TEMPLE UNIV OF THE COMMONWEALTH
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-15 至 2010-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7101515
• 关键词: adult human (21+); age difference; aging; behavioral /social science research tag; biomechanics; clinical research; computer human interaction; computer simulation; human old age (65+); human subject; mathematical model; motion perception; neural information processing; orientation; posture; proprioception /kinesthesia; sensory signal detection; stroke; vestibular pathway; visual fields; visual perception; young adult human (21-34)

DESCRIPTION (provided by applicant): The overall goal of this research is to determine how conflicting visual and self-motion information modulates the responses of the postural control system in elderly adults and in individuals post-stroke. When visual field information does not match self-motion feedback, healthy elderly respond to combined visual, vestibular, and proprioceptive signals differently than young adults. Young adults incorporate frequency components of all inputs into their responses; elderly adults rely primarily on vision. We hypothesize that elderly adults and individuals post-stroke have increased sensory thresholds to complex multimodal stimuli which produces a greater reliance on predictive or on visual inputs making it more difficult for them to selectively respond to visual and physical destabilization. By combining the technology of a virtual environment with support surface translations we plan to manipulate the influence of visual inputs, somatosensory (i.e., proprioceptive and vestibular) inputs, and prediction to reveal the contribution of segmental inputs and higher order processing to the postural response. We plan to compare healthy young and elderly individuals with young and elderly individuals post-stroke in order to distinguish between the effects of age and CNS impairment. We will first explore whether subjects change their responses to particular sensory modalities over time. Then the head and trunk will be aligned in different positions with respect to visual and support surface motion to reveal how altering sensory and biomechanical orientations affects the response to visual motion signals. Lastly, we will examine how predictable and random visual inputs influence the response to random support surface inputs. Visual field dependence will be measured with a Rod and Frame test. We will employ novel methods of Principal Component Analysis and autoregressive modeling to distinguish between body mechanics and specified neural processes. These analyses should reveal how the selection of control pathways is determined by the task as well as further define response properties of the afferent pathways. Segmental and muscle response strategies will be examined through kinematic measures including center of pressure, center of mass displacement, and electromyography, and tested for significance with a MANOVA. Clarifying the relation between visual inputs and postural stabilization will identify functional situations that present a high probability for instability and falling. Results from the proposed studies can potentially be used for developing individually designed programs of therapeutic intervention.

描述（由申请人提供）：本研究的总体目标是确定冲突的视觉和自我运动信息如何调节老年人和中风后个体的姿势控制系统的反应。当视野信息与自我运动反馈不匹配时，健康老年人对视觉、前庭和本体感觉信号的综合反应与年轻人不同。年轻人将所有输入的频率成分纳入他们的反应中；老年人主要依赖视力。我们假设老年人和中风后的个人对复杂的多模式刺激的感觉阈值增加，这会产生对预测或视觉输入的更大依赖，使他们更难以选择性地对视觉和身体不稳定做出反应。通过将虚拟环境技术与支持表面翻译相结合，我们计划操纵视觉输入、体感（即本体感觉和前庭）输入和预测的影响，以揭示分段输入和高阶处理对姿势反应的贡献。我们计划将健康的年轻人和老年人与中风后的年轻人和老年人进行比较，以区分年龄和中枢神经系统损伤的影响。我们将首先探讨受试者是否会随着时间的推移改变他们对特定感官模式的反应。然后，头部和躯干将在视觉和支撑表面运动的不同位置对齐，以揭示改变感觉和生物力学方向如何影响对视觉运动信号的响应。最后，我们将研究可预测和随机的视觉输入如何影响对随机支撑表面输入的响应。视野依赖性将通过杆和框架测试来测量。我们将采用主成分分析和自回归建模的新颖方法来区分身体力学和特定的神经过程。这些分析应该揭示任务如何决定控制路径的选择，并进一步定义传入路径的响应特性。将通过运动学测量（包括压力中心、质心位移和肌电图）检查节段和肌肉反应策略，并通过多元方差分析测试其显着性。澄清视觉输入和姿势稳定之间的关系将识别出极有可能出现不稳定和跌倒的功能情况。拟议研究的结果可用于开发单独设计的治疗干预计划。