NORMAL PHYSIOLOGY, PATHOPHYSIOLOGY, AND TREATMENT OF VOICE DISORDERS

基于数学优化的生物力学建模研究 证实环踝关节有一纵轴。 具有摇摆动作的环状关节。这与 假想的垂直轴的旋转。摇摆的动作减少了 两个关节曲面之间的距离的差异。被预测的 轨迹遵循与所获得的运动轨迹相同的路径 来自一个正常的说话者。 正常说话人不同发声时声带轨迹的研究 语音起始点显示了位移、速度和时间的差异。 它发现了一个统一的声带内收轨迹，比这三个 发声的类型。唯一的区别是声带之间的时间 闭合和发声，这表明差异在于 振动开始前声门下压力的积聚程度。 电刺激大鼠脑干c-fos表达的研究 显示引起内收肌反应的喉上神经 可能的喉部感觉-运动反应通路涉及 延髓外侧被盖区孤束核 网状结构，向胞核模糊。 感觉-运动性喉部反应条件反射的比较 内收肌痉挛发音障碍患者和正常对照组 完成。R_1和对侧R_2反应对 患者的条件性反应明显高于对照组。 然而，患者有正常的反应潜伏期和频率 非条件性反应表明脑干机制 这些反应没有受到影响。相反，结果表明，中央 内收肌痉挛发音困难时，反应的调制会发生改变。

A biomechanical modeling study employing mathematical optimization demonstrated that the cricoarytenoid joint had a longitudinal axis along the cricoid joint with a rocking action. This is in contrast to the hypothesized rotation of a vertical axis. The rocking motion reduced variance in the distance between the two joint surfaces. The predicted trajectories followed the same paths as movement trajectories obtained from a normal speaker. A study of vocal fold trajectories in normal speakers during different voice onsets demonstrated displacement, velocity and timing differences. It found a uniform trajectory for vocal fold adduction before all three types of voicing. The only difference was the time between vocal fold closure and voice onset which suggests that the differences were in the degree of buildup of subglottal pressure prior to vibration onset. A study of brain stem c fos expression with electrical stimulation of the superior laryngeal nerve which elicits the adductor response, demonstrated that the probable laryngeal sensori-motor response pathway involves the nucleus tractus solitarius, the lateral tegmental field in the medullary reticular formation, to the nucleus ambiguous. A comparison of sensori-motor laryngeal response conditioning between patients with adductor spasmodic dysphonia and normal control subjects was completed. The R1 and contralateral R2 responses have less inhibition of the conditioned responses in the patients than in the control subjects. However, the patients had normal response latencies and frequencies of unconditioned responses suggesting that the brain stem mechanisms for these responses were unaffected. Rather, the results suggest that central modulation of the responses is altered in adductor spasmodic dysphonia.