摘要
对15只正常豚鼠的ABR时域波形和频谱特征以及对18只豚鼠通过脑干核团立体定位技术,毁损听觉通路各不同部位后的时域波形及频谱改变进行了分析。实验证明:正常豚鼠90dBSPL短声诱发的ABR,呈现波Ⅰ、Ⅱ、Ⅲ、Ⅳ,通过平均功率谱分析,ABR频谱范围在50~2000Hz,有3个谱能量集中区,f0主峰中心频率为187.47±27.68Hz,f1为695.82±103.40Hz,f2为1103.67±81.55Hz。听觉通路不同部位毁损后,除影响一个时域主波形外,每个核团还不同程度地影响两个或两个以上波的形成。频谱图改变,有几个共同特点:(1)各谱峰中心频率向低频偏移;(2)谱分析带宽明显缩窄,高频截止区也向低频移动;(3)谱峰能量全面下降,甚至有的谱峰消失;(4)随毁损平面上行,谱能量损失减少,谱峰向低频区移动的程度降低。大多数核团对f1有贡献,听神经及低位脑子对f2的合成贡献较大,因此,应该认为ABR频谱特征是整个听觉通路各部位的综合效应。
An analysis was made of ABR frequency spectrum spectrum of 15 normal guinea pigs and 18 guinea pigs with the destruction of different plane of auditory pathway.The results indicated that the normal ABR spectral content was distributed around 50 ̄2000 Hz and characterized by three energy peaks:f0,f1 and f2.their frequencies being about 187,695 and 1103 Hz respectively.This study also demonstrated that a lesion of a single nuclus might affect not only a single component of the ABR,but also more typically on several other components.In the frequency domain analysis after destruction,there were several characteristics:(1)the positions of energy peaks moved to the low-frequency area;(2)the band of spectrum narrowed,i.e.the high cutoff frequency lowered;(3)decreasing in major peak energy,even some of peak;disappeared;(4)As the destroyed level rose,the degree of above changes fell.In addition, most of brain stem nuclei of auditory pathway made contribution to f1 and theⅧ th nerve and the nuclei of lower brain stem made more contributions to f2.Then it was considered that all sites in the brain stem auditory pathway had complex effects on the ABR frequency spectrum characteristics.
出处
《听力学及言语疾病杂志》
CAS
CSCD
1995年第2期57-61,共5页
Journal of Audiology and Speech Pathology