1 University of Wisconsin-Madison, WI, USA.
Trends Hear. 2018 Jan-Dec;22:2331216518775567. doi: 10.1177/2331216518775567.
This study evaluated spatial release from masking (SRM) in 2- to 3-year-old children who are deaf and were implanted with bilateral cochlear implants (BiCIs), and in age-matched normal-hearing (NH) toddlers. Here, we examined whether early activation of bilateral hearing has the potential to promote SRM that is similar to age-matched NH children. Listeners were 13 NH toddlers and 13 toddlers with BiCIs, ages 27 to 36 months. Speech reception thresholds (SRTs) were measured for target speech in front (0°) and for competitors that were either Colocated in front (0°) or Separated toward the right (+90°). SRM was computed as the difference between SRTs in the front versus in the asymmetrical condition. Results show that SRTs were higher in the BiCI than NH group in all conditions. Both groups had higher SRTs in the Colocated and Separated conditions compared with Quiet, indicating masking. SRM was significant only in the NH group. In the BiCI group, the group effect of SRM was not significant, likely limited by the small sample size; however, all but two children had SRM values within the NH range. This work shows that to some extent, the ability to use spatial cues for source segregation develops by age 2 to 3 in NH children and is attainable in most of the children in the BiCI group. There is potential for the paradigm used here to be used in clinical settings to evaluate outcomes of bilateral hearing in very young children.
本研究评估了 2-3 岁双侧人工耳蜗植入聋儿（BiCI）与年龄匹配的正常听力（NH）幼儿的空间掩蔽释放（SRM）。在此，我们研究了双侧听觉的早期激活是否具有促进与年龄匹配的 NH 儿童相似的 SRM 的潜力。研究对象为 13 名 NH 幼儿和 13 名 BiCI 幼儿，年龄为 27-36 个月。在正前方（0°）和同侧（0°）或对侧（+90°）竞争声源下，对目标语音进行语音接受阈（SRT）测量。SRM 计算为前方与非对称条件下 SRT 的差值。结果表明，BiCI 组的 SRT 在所有条件下均高于 NH 组。两组在同侧和对侧条件下的 SRT 均高于安静条件，表明存在掩蔽。仅在 NH 组中 SRM 具有统计学意义。BiCI 组的 SRM 组间差异无统计学意义，可能受样本量小限制；然而，除两名儿童外，其余儿童的 SRM 值均在 NH 范围内。本研究表明，在 NH 儿童中，到 2-3 岁时，利用空间线索进行声源分离的能力会在一定程度上发展，而在大多数 BiCI 组儿童中是可达到的。本研究中的范式具有在临床环境中评估幼儿双侧听力结果的潜力。
