噪声竞争对人工耳蜗植入儿童词汇提取的影响因素研究

It is increasing important to improve the postoperative language skills as the sustained rapid growth of younger children received cochlear implants (CIs). Specially, open set speech recognition ability in noise is the most key factor. However, there is little clarity as to the influence factor of the open set speech recognition in noise. Our pilot study indicated that lexical frequency, neighborhood density, and syllabic structure are vital factors to lexical selection in quiet. According to the pilot study, we hypothesized that those could also be basic factors for lexical selection in noise competition condition. During the study, we will use the noise introduced Standard Chinese Version of the Lexical Neighborhood Test and Multisyllabic Lexical Neighborhood Test system as the evaluation tool. The study will examine the potential factors, e.g., lexical frequency, neighborhood density, syllabic structure, and noise spectrum characteristics on lexical selection in noise condition for normal hearing children and CI children, respectively. We will also explore the noise effect on lexical activation, and establish the lexical selection modal to direct the noise reduction algorithm research and speech rehabilitation program.

我国低龄人工耳蜗植入（CI）者数量的持续快速增长使得如何提高其使用效益日渐重要，CI儿童噪声下开放式言语交流能力是最基础的关键因素。然而噪声竞争下CI儿童词汇提取的影响因素尚不明确，我们前期研究发现：安静条件下，目标词汇频率、邻域密度和音位结构对词汇提取起重要作用，据此提出假设：噪声竞争机制引入后，目标词的词汇学特征和音位结构是影响词汇提取的关键性因子，同时噪声频谱特性将影响词汇提取过程。研究中我们将在邻域激活模型基础上，对已建立的词汇相邻性测试系统引入噪声竞争机制，从行为心理学角度，利用结构方程模型的分析方法,通过对听力正常儿童和CI儿童的对比研究，观察噪声竞争下词汇频率、邻域密度、音位构成和噪声频谱特性对词汇提取的影响和关联性，探索噪声竞争对词汇激活和选择的作用，获得CI儿童噪声下词汇提取的特征性规律，为CI噪声抑制策略的研制提供理论依据，为临床开展科学化言语康复训练提供指导。

随着我国低龄人工耳蜗植入（CI）者数量的持续快速增长使得如何提高其使用效益日渐重要，CI儿童噪声下开放式言语交流能力是最基础的关键因素。安静条件下，目标词汇频率、邻域密度和音位结构对词汇提取起到重要作用。噪声竞争机制引入后，目标词汇的词汇学特征和音位结构是影响词汇提取的关键性因子，同时噪声频谱特性将影响词汇提取过程。课题组在邻域激活模型基础上，通过引入噪声竞争的词汇相邻性测试系统（语谱匹配噪声和多人谈话噪声），从行为心理学角度，利用结构方程模型的方法分析，完成噪声竞争对汉语普通话CI儿童言语识别的影响作用研究。通过执行本项目获得噪声竞争下，噪声强度、目标词汇频率、邻域密度及音位学特征在汉语普通话CI儿童中枢听觉记忆组织和言语识别进程中的作用权重，确定各因素之间的相互影响和关联作用。获得噪声频谱特性对汉语普通话CI儿童强度-识别函数曲线的影响规律，得到汉语普通话CI儿童在不同噪声频谱特性下的抗噪性规律。本项研究为CI噪声抑制策略的研制提供理论依据，为临床开展科学化言语康复训练提供指导。