Young I M, Lowry L D
Department of Otolaryngology-Head and Neck Surgery, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA.
Yonsei Med J. 1994 Mar;35(1):84-90. doi: 10.3349/ymj.1994.35.1.84.
Horizontal eye movements were recorded by electronystagmography in a subject with a plug of granulation tissue in the unilateral horizontal semicircular canal by the room temperature air caloric stimulation. Stimuli were sequentially presented to both ears with the subject supine and prone, keeping the horizontal canal vertical. Caloric stimuli presented to the unplugged ear resulted in a vestibular nystagmus whose slow phase eye velocity (SPEV) was always directed toward the stimulated side when the subject was supine and toward the opposite side when he was prone. In contrast, calorics presented to the horizontal canal plugged ear showed that SPEV was always directed toward the stimulated side, irrespective of whether the subject was supine or prone. Results were consistent with consensus that the caloric responses noted in the horizontal canal plugged ear reflected horizontal canal afferent activity which may correspond to direct effect of temperature on end organs or afferents. The findings imply that a caloric mechanism exists which is independent of the conventionally accepted one involving concection currents within the canal.
通过室温空气冷热试验刺激，对一名单侧水平半规管有肉芽组织堵塞物的受试者进行眼震电图记录水平眼动。受试者仰卧和俯卧时，刺激依次施加于双耳，保持水平半规管垂直。对未堵塞耳施加冷热刺激时，会引发前庭眼震，当受试者仰卧时，眼震慢相眼速度（SPEV）总是指向受刺激侧，而当受试者俯卧时则指向对侧。相比之下，对水平半规管堵塞耳施加冷热刺激时，无论受试者是仰卧还是俯卧，SPEV总是指向受刺激侧。结果与以下共识一致，即水平半规管堵塞耳中记录到的冷热反应反映了水平半规管传入活动，这可能对应于温度对终器或传入神经的直接影响。这些发现表明存在一种冷热机制，它独立于传统上认为的涉及半规管内对流电流的机制。
