Nourski Kirill V, Abbas Paul J, Miller Charles A, Robinson Barbara K, Jeng Fuh-Cherng
Department of Otolaryngology - Head and Neck Surgery, University of Iowa, Iowa City, 52242, USA.
Hear Res. 2005 Apr;202(1-2):141-53. doi: 10.1016/j.heares.2004.10.001.
This study investigated the effects of acoustic noise on the auditory nerve compound action potentials in response to electric pulse trains. Subjects were adult guinea pigs, implanted with a minimally invasive electrode to preserve acoustic sensitivity. Electrically evoked compound action potentials (ECAP) were recorded from the auditory nerve trunk in response to electric pulse trains both during and after the presentation of acoustic white noise. Simultaneously presented acoustic noise produced a decrease in ECAP amplitude. The effect of the acoustic masker on the electric probe was greatest at the onset of the acoustic stimulus and it was followed by a partial recovery of the ECAP amplitude. Following cessation of the acoustic noise, ECAP amplitude recovered over a period of approximately 100-200 ms. The effects of the acoustic noise were more prominent at lower electric pulse rates (interpulse intervals of 3 ms and higher). At higher pulse rates, the ECAP adaptation to the electric pulse train alone was larger and the acoustic noise, when presented, produced little additional effect. The observed effects of noise on ECAP were the greatest at high electric stimulus levels and, for a particular electric stimulus level, at high acoustic noise levels.
本研究调查了声学噪声对响应电脉冲序列的听神经复合动作电位的影响。实验对象为成年豚鼠，植入微创电极以保留声学敏感性。在呈现声学白噪声期间和之后，记录听神经干对电脉冲序列的电诱发复合动作电位（ECAP）。同时呈现的声学噪声导致ECAP幅度降低。声学掩蔽器对电探针的影响在声学刺激开始时最大，随后ECAP幅度部分恢复。声学噪声停止后，ECAP幅度在约100 - 200毫秒的时间内恢复。在较低的电脉冲频率（脉冲间隔为3毫秒及更高）下，声学噪声的影响更为显著。在较高的脉冲频率下，ECAP对单独电脉冲序列的适应性更大，当呈现声学噪声时，产生的额外影响很小。观察到的噪声对ECAP的影响在高电刺激水平时最大，并且对于特定的电刺激水平，在高声学噪声水平时影响最大。
