耳蜗畸变产物与耳蜗活性关系的激光干涉研究  

Relationship of distortion product in cochlea with cochlear activity revealed by laser interferometry

作　　者：龙贤明[1] 张艳平[2] 鲁杰[3] 龙长才[3] 

机构地区：[1]汉川市人民医院神经外科,湖北汉川431600 [2]华中科技大学校医院 [3]华中科技大学物理学院

出　　处：《临床耳鼻咽喉头颈外科杂志》2015年第18期1644-1647,共4页Journal of Clinical Otorhinolaryngology Head And Neck Surgery

基　　金：国家自然科学基金(No:11374118);湖北省自然科学基金(No:2013CFB280)

摘　　要：目的:研究耳蜗中畸变产物与耳蜗活性及听觉感知的关系。方法:对20例刚从豚鼠活体分离耳蜗,用激光干涉记录其基膜在频率为1=1 000Hz、2=1 400 Hz声激励下的振动,直致基膜振动信号完全消失。通过频谱分析,得到基膜振动信号中畸变产物以及激励信号成份随耳蜗离体时间的变化。结果:耳蜗离体后半小时内,基膜振动中除了有激励信号的振动外,均观察到畸变成份,同时还能观察到两音抑制效应。随着时间推移,畸变产物以及激励信号频率成份的幅度均不断减小。最后,畸变产物率先在基膜振动信号中消失,而激励频率成份1、2信号则在畸变产物消失后持续存在了一段时间才消失。在畸变产物消失后,基膜的振幅显著减小,两音抑制效应也同时消失。结论:耳蜗中畸变产物是耳蜗主动活性的标志,正是这一活性使得基膜对激励信号有更大幅度振动响应并产生听觉中的两音抑制效应。前者使得听觉具有高的灵敏度,从而感知小的声音激励,后者使得听觉能增强和提取有意义的声信号特征。Objective：To study the relationship of distortion product in cochlea with cochlear activity and hear- ing. Method：Time variances of distortion product of basilar membrane vibration in vitro guineapig cochlea were ob- served by laser interferometry. Result： Within half hour after a cochlea was isolated from a guineapig, distortion product accompanied with two-tone inhibition in cochlea, can be observed. As time passed, distortion product andtwo-tone inhibiton effect disappeared at the same time. After that, the membrane contiune vibrating in response to the sound stimulus, but the vibration amplitude decreased obviously and continued decreasing until it disappeared completely. Conclusion：Distortion product in cochlea is a symbol of cochlear activity which makes the membrane re- spond in large amplitude vibration to sound stimulus and exhibit two-tone inhibition. The former makes the hear- ing highly sensitive to sound stimulus, the later makes the hearing perform information abstract well.

关 键 词：耳蜗 基膜的振动 畸变产物 激光干涉测量法 

分 类 号：R764.35[医药卫生—耳鼻咽喉科]