Optimizing speech coding strategies for noise and music

描述（由申请人提供）：人工耳蜗使用者的言语理解能力多年来稳步提高。然而，在嘈杂的听力条件下，Cl用户的语音感知性能急剧下降。此外，Cl用户无法识别熟悉的旋律并享受音乐。有些Cl患者认为音乐是“有节奏的噪音”。在噪音中交流和欣赏音乐仍然是人工耳蜗的两大挑战。对于导致Cl使用者在噪音和识别熟悉的旋律方面表现不佳的因素，人们知之甚少。在这个项目中，我们提出了一系列旨在分离这些因素的实验。我们提出了适合音乐和噪声的新的信号处理算法。提出的实验有五个具体目的。第一个目的是评估精细结构和包络信息在噪声条件下对单词识别的相对贡献。第二个目的是研究两种降噪算法的性能，这两种算法保留了良好的时间线索和/或包络线索。提出了一种针对个人用户定制和优化降噪算法的方法。第三个目标是评估精细结构和包络信息对旋律识别的相对贡献。

DESCRIPTION (provided by applicant): The speech understanding capabilities of cochlear implant (Cl) users have increased steadily throughout the years. However, speech perception performance of Cl users drops tremendously in noisy listening conditions. Also, Cl users are unable to identify familiar melodies and enjoy music. Some Cl patients refer to music as "noise with rhythm". Communicating in noise and enjoying music still remain the two biggest challenges in cochlear implants. Little is known about the factors that contribute to the poor performance of Cl users in noise and in identifying familiar melodies. In this project, we propose a series of experiments aimed at isolating these factors. We propose new signal processing algorithms tailored for music and noise. The proposed experiments have five specific aims. The first aim assesses the relative contribution of fine structure and envelope information on word recognition in noise. The second aim investigates the performance of two noise reduction algorithms that preserve fine temporal cues and/or envelope cues. A method for customizing and optimizing the noise reduction algorithms to individual users is proposed. The third aim assesses the relative contribution of fine structure and envelope information on melody recognition. The fourth aim investigates the performance of a new strategy that incorporates fine-structure information for better music perception. The last aim investigates the performance of a desynchronizing strategy which can be used for subjects who would otherwise not be able to receive any benefit from the strategies proposed in the previous aims for speech or music. The five aims taken together will produce speech/music coding algorithms that will be optimally fit to individual users. The results of the above experiments will lay the groundwork for a better understanding on the importance of fine structure cues for speech understanding in noise and for music appreciation by Cl listeners. It will also open new avenues for the development of future signal processing strategies for cochlear implants that could potentially be used to improve not only speech intelligibility but also speaker identification and tonal language recognition.