Knox Joanna, Cordo Paul, Skoss Rachel, Durrant Shane, Hodges Paul
Division of Psychotherapy, University of Queensland, Brisbane, Australia.
Behav Neurosci. 2006 Dec;120(6):1211-7. doi: 10.1037/0735-7044.120.6.1211.
Acuity for elbow joint position sense (JPS) is reduced when head position is modified. Movement of the head is associated with biomechanical changes in the neck and shoulder musculoskeletal system, which may explain changes in elbow JPS. The present study aimed to determine whether elbow JPS is also influenced by illusory changes in head position. Simultaneous vibration of sternocleidomastoid (SCM) and the contralateral splenius was applied to 14 healthy adult human subjects. Muscle vibration or passive head rotation was introduced between presentation and reproduction of a target elbow position. Ten out of 14 subjects reported illusions consistent with lengthening of the vibrated muscles. In these 10 subjects, absolute error for elbow JPS increased with left SCM/right splenius vibration but not with right SCM/left splenius vibration. Absolute error also increased with right rotation, with a trend for increased error with left rotation. These results demonstrated that both actual and illusory changes in head position are associated with diminished acuity for elbow JPS, suggesting that the influence of head position on upper limb JPS depends, at least partially, on perceived head position.
当头部位置改变时，肘关节位置觉（JPS）的敏锐度会降低。头部的运动与颈部和肩部肌肉骨骼系统的生物力学变化相关，这可能解释了肘关节JPS的变化。本研究旨在确定肘关节JPS是否也受头部位置的虚幻变化影响。对14名健康成年受试者同时施加胸锁乳突肌（SCM）和对侧斜方肌的振动。在目标肘关节位置的呈现和再现之间引入肌肉振动或被动头部旋转。14名受试者中有10名报告了与振动肌肉延长一致的错觉。在这10名受试者中，肘关节JPS的绝对误差随左侧SCM/右侧斜方肌振动而增加，但随右侧SCM/左侧斜方肌振动则未增加。绝对误差也随右侧旋转而增加，左侧旋转时有误差增加的趋势。这些结果表明，头部位置的实际和虚幻变化均与肘关节JPS敏锐度降低相关，提示头部位置对上肢JPS的影响至少部分取决于感知到的头部位置。
