Dynamics of Postural Control During Precision Manual Activity

站立平衡的控制是人们进行其他行为的基础，例如外科医生或艺术家进行精确的手部运动。由于站立需要将身体置于一种不稳定的状态，并且由于神经肌肉系统高度复杂和“嘈杂”，当一个人站立时，身体的重心会不断波动（称为姿势摇摆）。姿势的摇摆会传递到手上，因此会妨碍手工操作（想象一下单脚站着穿针引线）。这项提议的目的是确定当人们用指尖轻触表面的精确手动动作时，姿势控制是如何调节的。本研究将探讨体位控制与精确手动动作相结合的自适应体位动力学。实验计划中，姿势稳定性和指尖力生产任务的需求是不同的。在平衡不受威胁的情况下，体位摇摆的可变性和时间动态有望精确地调整到触摸任务的要求，但对体位稳定性的威胁有望限制体位控制适应手动任务的程度。该研究将揭示平衡控制的基本机制，并将在物理康复和努力制定跌倒预防计划方面具有重要应用。

Dynamics of Postural Control During Precision Manual ActivityMichael Riley (PI) & Kevin Shockley (Co-PI)AbstractThe control of standing balance is fundamental to other behaviors people perform, such as the precise hand movements performed by surgeons or artists. Since standing upright requires placing the body in an unstable state, and because the neuromuscular system is highly complex and "noisy,"the body's center of mass constantly fluctuates when a person stands (termed postural sway). Postural sway is transmitted to the hands and can thus hinder manual performance (imagine trying to thread a needle whilestanding on one foot). The purpose of this proposal is to determine how postural control is modulated when people perform the precision manual action of lightly touching a surface with a fingertip.The research will identify the adaptive postural dynamics associated with integrating postural control and precision manual actions. Experiments are planned in which postural stability and the demands of a fingertip force-production task are varied. The variability and temporal dynamics of postural sway are expected to be precisely tuned to the demands of the touching task under conditions in which balance is not threatened, but threats to postural stability are expected to limit the extent to which postural control is adapted to the manual task. The research will shed light on fundamental mechanisms of balance control and will also have important applications to physical rehabilitation and efforts to develop fall-prevention programs.