幼猫鼓阶内慢性电刺激生理学研究

A Physiological Investigation of Chronic Electrical Stimulation with Scala Tympani Electrodes in Kittens

本实验用6只生后2个月的幼猫植入鼓阶电极行慢性电刺激以探讨电听觉的生理学特征。观察到:(1)安全范围内的慢性电刺激对幼猫听力无者害的影响,亦未影响脑干听觉通路对声、电刺激产生的冲动的传递过程;(2)除Ⅰ波被刺激伪迹掩盖外,EABR波形与ABR相似,但前者各波潜伏期随强度改变小,绝对潜伏期比ABR短约1.5ms,波间间期也有意义地缩短;(3)EABR输入——输出曲线电刺激后比电刺激前明显左移。

A physiological investigation of cochlear electrical stimulation was undertaken in six two-month-old kittens.The scala tympani electrodes were implanted and electrically stimulated using biphasic balanced electrical pulses for periods of 1000-1500h in four ears. Four ears received implants for same period but without electrical stimulation. The other two ears served as normal control.The results indicated: 1) Chronic electrical stimulation of the cochlea within electrochemically safe limits did not influence the hearing of kittens and the normal delivery of impulses evoked by acoustic and electrical signals on . the auditory brainstem pathway. 2) The wave shapes of EABRs were similar to those of ABRs. The amplitudes of EABRs showed a significant increase following chronic electrical stimulation, resulting in a leftward shift in the input/ output function. The absolute latencies and interwave latencies of waves Ⅱ-Ⅲ, Ⅲ-Ⅳ and Ⅱ-Ⅳ were significantly shorter than those of ABRs.These results imply that there was no adverse effect of chronic electrical stimulation on the maturing auditory systems of kittens using these electrical parameters and the mechanism of electrical hearing should be further studied.