| Objective: Acoustically evoked short latency negative response (ASNR) is present in ears with profound hearing loss under intense stimulation. It is reported that the presence of ASNR was consistent with vestibular evoked myogenic potential (VEMP) and not correlated with caloric test, suggesting that ASNR and VEMP are both originated from saccule. This study was designed to evoke ASNR in normal people with a technique of intense clicks combined with masking , which simulates profound sensory hearing loss in normal ears.Methods: 20 healthy normal hearing subjects were employed. Auditory brainstem response (ABR) and VEMP were recorded. ASNR was elicited through combination of air conduction click stimulation and bone conduction white nosie masking Potential latency, occurrence rate and relationships were studied.Results: Out of 20 healthy normal- hearing subjects(40 ears), ASNR was elicited in 12 ears(30%), the threshold of ASNR was 95-105dB nHL, the mean of threshold was 97.5±5.24 dB nHL, the threshold of masking noise was 75- 90dB nHL, the mean of threshold was 81.67±7.53dB nHL. It's latency was 2.72-3.36ms, the mean was 3.11±0.15ms . The mean latency of threshold was 3.02±0.16ms. VEMP was elicited in 19 ears(47.5%), the latency of P13 was 11.92-14.15 ms, the mean latency of P13 was12.81±0.83ms, the latency of N23 was18.98-22.19ms, the mean latency of N23 was 20.52±0.89ms. Significant consistence was reveal between the presence of ASNR and VEMP.Conclusions: The presence of ASNR is dependent on saccular function, it has been confirmed that ASNR can be evoked in profound loss hearing ear. This study presented white noise through a bone vibrator to mask ABR components imitating sensory deafness, without the overlap of ABR air conduction click stimuli evoked ASNR was clearly demonstrated. Based on the results, we believe that ASNR is not only present in profound loss hearing ears, but also healthy ones.
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