交叉听力对豚鼠听性脑干反应测试的影响

The effect of cross-hearing on auditory brain-stem response of guinea pigs

报告对8只听觉正常的豚鼠,观察交叉听力对其耳蜗动作电位(AP)和听性脑干反应(ABR)测试结果的影响。先手术造成其左耳全聋<术耳),然后用四种方法分别记录ABR反应阈和Ⅰ波(或N_1)潜伏期。结果发现,术耳虽已全聋,但该侧给声强度达10dB HL以上时仍可记录到ABR,而AP未能引出,代之出现的却是清晰的ABR波形。提示当豚鼠双耳听阈相差达10dB HL以上,在测试听力较差一耳的ABR时,则可能发生交叉听打现象;AP是准确地测定豚鼠听功能较理想的指标;若用ABR进行观察,则应注意在实验中消除交叉听力对ABR的影响。

Cross-hearing is a common phenomenon in clinical audiometry,However ,its affection on ABR of guinea pigs was not reported previously. In this paper,eight guinea pigs with normal hearing(ABR 10dB HL) were selected to test ABR and action potential(AP). At first,the left ears of the detected animals were destroyed by surgery under anaesthesia,and then recorded their evoked potentials by four methods. The results of animal experiment suggested that ABR of guinea pigs was influenced severely by cross-hearing if the stimulated sound was delivered to an external ear canal of guinea pig through the earphone when hearing of its opposite ear existed. On the other hand ,AP of guinea pigs was not impacted by cross-hearing at all. Therefore,cross-hearing must be considered while ABR is as an indicator in the animal experiment. Some reasons were also discussed.