Department of Communication Sciences and Disorders, University of South Florida, Tampa, FL, USA.
Department of Hearing and Speech Sciences, University of Maryland, College Park, MD, USA.
Int J Audiol. 2020 Jun;59(6):434-442. doi: 10.1080/14992027.2020.1718782. Epub 2020 Jan 31.
The present study was motivated by a need for a speech intelligibility test capable of indexing dynamic changes in the environment and adaptive processing in hearing aids. The Continuous Number Identification Test (CNIT) was developed to meet these aims. From one location in the free field, speech was presented in noise (∼2 words/s) with a 100-ms inter-word interval. On average, every fourth word was a target digit and all other words were monosyllabic words. Non-numeric words had a fixed presentation level such that the dominant signal-to-noise-ratio (SNR) was held at +6 dB SNR relative to background maskers. To prevent ceiling effects, however, targets were presented at a user-specific SNR, determined by an initial adaptive-tracking procedure that estimated the 79.4% speech reception threshold. Ten normal-hearing listeners participated. The CNIT showed comparable psychometric qualities of other established speech tests for long time scales (Exp. 1). Target-location changes did not affect performance on the CNIT (Exp. 2), but the test did show high temporal resolution in assessing sudden changes to SNR (Exp. 3). The CNIT is highly customisable, and the initial experiments tested feasibility of its primary features which set it apart from currently available speech-in-noise tests.
本研究的目的是开发一种能够对环境变化和助听器自适应处理进行索引的言语可懂度测试。连续数字识别测试（CNIT）正是为了满足这些目标而开发的。在自由场的一个位置，以噪声（约 2 个词/秒）的形式呈现语音，词与词之间的间隔为 100 毫秒。平均而言，每第四个词是目标数字，其他所有词都是单音节词。非数字词的呈现水平固定，使得相对于背景掩蔽的主导信噪比（SNR）保持在+6dB SNR。然而，为了防止天花板效应，目标词以用户特定的 SNR 呈现，这是通过初始自适应跟踪程序确定的，该程序估计了 79.4%的言语接受阈值。10 名正常听力听众参与了测试。CNIT 在长时间尺度上与其他已建立的言语测试具有可比的心理测量质量（实验 1）。目标位置的变化不会影响 CNIT 的性能（实验 2），但该测试确实在评估 SNR 突然变化方面表现出了很高的时间分辨率（实验 3）。CNIT 具有高度的可定制性，最初的实验测试了其主要功能的可行性，这些功能使其有别于目前可用的噪声下言语测试。
