Reginella R L, Redfern M S, Furman J M
Department of Bioengineering, University of Pittsburgh, PA 15213, USA.
J Vestib Res. 1999;9(2):103-9.
Sensory information from lightly touching a reference with the hand is known to influence postural sway in young adults. The primary aim of this study was to compare the influence of finger contact (FC) with an earth-fixed reference to the influence of FC with a body-fixed reference. A second goal of this study was to determine if FC is used differently by older adults compared to younger adults. Using a force plate, center of pressure at the feet was recorded from blindfolded young and older subjects during several conditions. Subjects either did or did not lightly touch a force-sensitive plate that was either earth-fixed or moved forward and backward in synchrony with body sway (that is, sway-referenced). In addition, support surface conditions were also varied, including a fixed floor and a sway-referenced floor using an Equitest. Results showed that the type of FC, floor condition, and age each had an effect on postural sway. Touching an earth-fixed plate decreased postural sway as compared to no touching, while touching a sway-referenced plate increased sway. This influence of FC was enhanced when the floor was sway-referenced. Although older subjects swayed more than young subjects overall, no age-FC interactions occurred, indicating that FC was not utilized differently between the age groups. This study suggests that FC cannot be disregarded as erroneous, especially when proprioceptive information from the legs is distorted. Further, FC is integrated with other sensory information by the postural control system similarly in young and older persons.
众所周知，用手轻轻触碰一个参考物所产生的感觉信息会影响年轻人的姿势摆动。本研究的主要目的是比较手指接触（FC）固定于地面的参考物与接触固定于身体的参考物所产生的影响。本研究的第二个目标是确定老年人与年轻人对手指接触的使用方式是否不同。使用测力板，在几种情况下记录了蒙眼的年轻人和老年人双脚的压力中心。受试者要么轻轻触碰一个固定于地面的力敏板，要么不触碰，该力敏板要么固定于地面，要么与身体摆动同步前后移动（即摆动参考）。此外，支撑面条件也有所不同，包括固定地面和使用Equitest的摆动参考地面。结果表明，手指接触的类型、地面条件和年龄均对姿势摆动有影响。与不触碰相比，触碰固定于地面的板子会减少姿势摆动，而触碰摆动参考的板子则会增加摆动。当地面为摆动参考时，手指接触的这种影响会增强。尽管老年受试者总体上比年轻受试者摆动得更多，但未出现年龄与手指接触的交互作用，这表明不同年龄组对手指接触的利用方式并无差异。本研究表明，手指接触不能被视为错误信息而被忽视，尤其是当来自腿部的本体感觉信息失真时。此外，年轻人和老年人的姿势控制系统对手指接触与其他感觉信息的整合方式类似。
