1 Department of Speech and Hearing Sciences, University of Washington, Seattle, WA, USA.
Trends Hear. 2018 Jan-Dec;22:2331216518770959. doi: 10.1177/2331216518770959.
Children's performance on psychoacoustic tasks improves with age, but inadequate auditory input may delay this maturation. Cochlear implant (CI) users receive a degraded auditory signal with reduced frequency resolution compared with normal, acoustic hearing; thus, immature auditory abilities may contribute to the variation among pediatric CI users' speech recognition scores. This study investigated relationships between age-related variables, spectral resolution, and vowel identification scores in prelingually deafened, early-implanted children with CIs compared with normal hearing (NH) children. All participants performed vowel identification and the Spectral-temporally Modulated Ripple Test (SMRT). Vowel stimuli for NH children were vocoded to simulate the reduced spectral resolution of CI hearing. Age positively predicted NH children's vocoded vowel identification scores, but time with the CI was a stronger predictor of vowel recognition and SMRT performance of children with CIs. For both groups, SMRT thresholds were related to vowel identification performance, analogous to previous findings in adults. Sequential information analysis of vowel feature perception indicated greater transmission of duration-related information compared with formant features in both groups of children. In addition, the amount of F2 information transmitted predicted SMRT thresholds in children with NH and with CIs. Comparisons between the two CIs of bilaterally implanted children revealed disparate task performance levels and information transmission values within the same child. These findings indicate that adequate auditory experience contributes to auditory perceptual abilities of pediatric CI users. Further, factors related to individual CIs may be more relevant to psychoacoustic task performance than are the overall capabilities of the child.
儿童在听力学任务上的表现会随着年龄的增长而提高，但听觉输入不足可能会延迟这种成熟。与正常听力相比，人工耳蜗（CI）使用者接收到的听觉信号质量较差，频率分辨率降低；因此，不成熟的听觉能力可能会导致儿童人工耳蜗使用者的言语识别得分存在差异。本研究调查了与年龄相关的变量、频谱分辨率以及人工耳蜗植入的聋儿与正常听力（NH）儿童的元音识别分数之间的关系。所有参与者都进行了元音识别和频谱时变调制波纹测试（SMRT）。NH 儿童的元音刺激被语音编码以模拟 CI 听觉的降低频谱分辨率。年龄对 NH 儿童的语音编码元音识别分数有积极的预测作用，但 CI 时间对 CI 植入儿童的元音识别和 SMRT 表现的预测作用更强。对于两组儿童，SMRT 阈值与元音识别性能相关，这与成人的先前发现类似。元音特征感知的顺序信息分析表明，与成人相比，两组儿童都更能传递与持续时间相关的信息，而不是与共振峰特征相关的信息。此外，F2 信息的传递量可以预测 NH 儿童和 CI 植入儿童的 SMRT 阈值。对双侧植入儿童的两个 CI 进行比较，发现同一儿童的任务表现水平和信息传递值存在差异。这些发现表明，充足的听觉体验有助于儿童人工耳蜗使用者的听觉感知能力。此外，与儿童的整体能力相比，与个体 CI 相关的因素可能与心理声学任务表现更相关。
