Martin Brett A
Montclair State University, Program in Audiology, Clifton, NJ, USA.
J Am Acad Audiol. 2007 Feb;18(2):126-40. doi: 10.3766/jaaa.18.2.5.
The purpose of this case study was to determine whether the P1-N1-P2 acoustic change complex (ACC) could be recorded in an individual with a cochlear implant. In a cochlear implant recipient, stimulus-related artifact from the implant can overlap the evoked potential of interest, making it difficult to determine whether the recorded response is neural or a simple reflection of the artifact. This is an even greater technical challenge for the ACC because stimuli having relatively long durations are used. The subject was a 24-year-old with a diagnosis of auditory neuropathy/auditory dys-synchrony and used a MED-EL Tempo+ cochlear implant in her left ear. The ACC was recorded to synthetic vowels containing a change of F2 at midpoint ranging from 0 (no change) to 1200 Hz (perceived as /ui/). The stimuli were presented randomly at 75 dB SPL via a loudspeaker. In one condition the subject ignored the stimuli and watched a captioned video. In the other, the subject pressed one button on a response pad if she perceived an acoustic change at stimulus midpoint and another if she did not. Cortical auditory evoked potentials were recorded from 32 scalp electrodes. Results indicated that the ACC was present and could be teased apart from the cochlear implant stimulus artifact. ACC thresholds showed good agreement with behavioral discrimination performance, and therefore, results are positive for the potential clinical application of the ACC technique to individuals with cochlear implants.
本案例研究的目的是确定在一名接受人工耳蜗植入的个体中是否能够记录到P1-N1-P2听觉变化复合体（ACC）。在人工耳蜗植入受者中，植入物产生的与刺激相关的伪迹可能会与感兴趣的诱发电位重叠，从而难以确定所记录的反应是神经反应还是仅仅是伪迹的简单反映。对于ACC来说，这是一个更大的技术挑战，因为使用的刺激持续时间相对较长。受试者是一名24岁女性，诊断为听觉神经病/听觉失同步，左耳使用MED-EL Tempo+人工耳蜗。记录了对包含F2在中点处从0（无变化）到1200赫兹变化（被感知为/ ui /）的合成元音的ACC。刺激通过扬声器以75分贝声压级随机呈现。在一种情况下，受试者忽略刺激并观看带字幕的视频。在另一种情况下，如果受试者在刺激中点处感知到声学变化，她就在反应垫上按下一个按钮；如果没有感知到，则按下另一个按钮。从32个头皮电极记录皮层听觉诱发电位。结果表明存在ACC，并且可以将其与人工耳蜗刺激伪迹区分开来。ACC阈值与行为辨别性能显示出良好的一致性，因此，对于ACC技术在人工耳蜗植入个体中的潜在临床应用而言，结果是积极的。
