1Department of Otolaryngology/Head & Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA; 2Department of Audiology, UNC Healthcare, Chapel Hill, North Carolina, USA; and 3Department of Otolaryngology/Head & Neck Surgery, Washington University, Saint Louis, Missouri, USA.
Ear Hear. 2017 Sep/Oct;38(5):611-619. doi: 10.1097/AUD.0000000000000430.
The present study evaluated early auditory localization abilities of cochlear implant (CI) recipients with normal or near-normal hearing (NH) in the contralateral ear. The goal of the study was to better understand the effect of CI listening experience on localization in this population.
Twenty participants with unilateral hearing loss enrolled in a prospective clinical trial assessing outcomes of cochlear implantation (ClinicalTrials.gov Identifier: NCT02203305). All participants received the MED-EL Standard electrode array, were fit with an ear-level audio processor, and listened with the FS4 coding strategy. Localization was assessed in the sound field using an 11-speaker array with speakers uniformly positioned on a horizontal, semicircular frame. Stimuli were 200-msec speech-shaped noise bursts. The intensity level (52, 62, and 72 dB SPL) and sound source were randomly interleaved across trials. Participants were tested preoperatively, and 1, 3, and 6 months after activation of the audio processor. Performance was evaluated in two conditions at each interval: (1) unaided (NH ear alone [NH-alone] condition), and (2) aided, with either a bone conduction hearing aid (preoperative interval; bone conduction hearing aid + NH condition) or a CI (postoperative intervals; CI + NH condition). Performance was evaluated by comparing root-mean-squared (RMS) error between listening conditions and between measurement intervals.
Mean RMS error for the soft, medium, and loud levels were 66°, 64°, and 69° in the NH-alone condition and 72°, 66°, and 70° in the bone conduction hearing aid + NH condition. Participants experienced a significant improvement in localization in the CI + NH condition at the 1-month interval (38°, 35°, and 38°) as compared with the preoperative NH-alone condition. Localization in the CI + NH condition continued to improve through the 6-month interval. Mean RMS errors were 28°, 25°, and 28° in the CI + NH condition at the 6-month interval.
Adult CI recipients with normal or near-normal hearing in the contralateral ear experienced significant improvement in localization after 1 month of device use, and continued to improve through the 6-month interval. The present results show that binaural acclimatization in CI users with unilateral hearing loss can progress rapidly, with marked improvements in performance observed after only 1 month of listening experience.
本研究评估了对侧耳正常或接近正常听力（NH）的人工耳蜗（CI）植入者的早期听觉定位能力。研究的目的是更好地了解 CI 聆听体验对该人群定位的影响。
20 名单侧听力损失患者参加了一项评估人工耳蜗植入（ClinicalTrials.gov 标识符：NCT02203305）结果的前瞻性临床试验。所有参与者均接受 MED-EL 标准电极阵列，配备耳级音频处理器，并使用 FS4 编码策略进行聆听。使用具有均匀布置在水平半圆形框架上的 11 个扬声器的阵列在声场中评估定位。刺激物为 200 毫秒的语音形状噪声突发。在每次试验中，强度水平（52、62 和 72 dB SPL）和声源随机交错。参与者在术前以及激活音频处理器后的 1、3 和 6 个月进行测试。在每个间隔的两种情况下评估性能：（1）未辅助（NH 耳单独[NH-alone]条件），和（2）辅助，使用骨导助听器（术前间隔；骨导助听器+NH 条件）或 CI（术后间隔；CI+NH 条件）。通过比较听力条件和测量间隔之间的均方根（RMS）误差来评估性能。
NH-alone 条件下软、中、高声级的平均 RMS 误差分别为 66°、64°和 69°，骨导助听器+NH 条件下分别为 72°、66°和 70°。与术前 NH-alone 条件相比，CI+NH 条件下的参与者在术后 1 个月时的定位能力显著提高（38°、35°和 38°）。在 6 个月的间隔内，CI+NH 条件下的定位继续改善。6 个月间隔时，CI+NH 条件下的平均 RMS 误差为 28°、25°和 28°。
对侧耳正常或接近正常听力的成年 CI 植入者在使用设备 1 个月后经历了定位能力的显著提高，并且在 6 个月的间隔内继续提高。目前的结果表明，单侧听力损失的 CI 用户的双耳适应可以迅速发展，仅在 1 个月的聆听体验后观察到显著的性能提高。
