上肢姿勢保持時における布の接触からの触覚位置入力が生理的振戦に及ぼす影響

抄録

This study investigated the effect of haptic and position sensory input through contact with cloth on physiological tremor (PT) during postural maintenance. Eleven healthy, right-handed females in the sitting position were asked to raise their left upper limbs forward while extending their hands and fingers for 30 s under two different conditions. One condition was to normally hold this posture. The other was to maintain the posture while the forearm was in light contact with a piece of cloth. During posture maintenance, the PT signal of the forearm was measured using an acceleration sensor and analyzed by power spectrum analysis. The amplitude of PT decreased significantly during contact with the cloth. This decrease was primarily influenced by frequency components < 4.9 Hz. Furthermore, changes in amplitude of PT correlated with changes in frequency components < 4.9 Hz (r = 0.85, p < 0.01). These findings suggest that the haptic sensory input through light contact with cloth provides information about the relative movement of the limb. This contact allows posture to be maintained easily because of the influence of the stretch reflex mechanism (frequency components < 4.9 Hz).