COMPLEX AUDITORY PROCESSING WITH COCHLEAR IMPLANTS

描述（由申请人提供）：耳蜗植入体（CI）成功地为严重听力受损和深度耳聋患者提供听觉信息。然而，它们在嘈杂的背景下或在竞争扬声器存在的情况下不成功。虽然研究表明，大脑可以通过自上而下的处理来适应不利的听力条件，但当传输到听觉系统的信息严重退化时，学习和自上而下的机制只能在有限的程度上起作用。我们工作的长期目标是揭示CI听者听觉敏感性的基本机制，并将这些发现与他们使用设备的语音感知联系起来。越来越明显的是，为了提高声音质量、说话人识别、源分离和在噪声中收听，CI将需要提供关于语音频谱的细粒度信息。目前还不清楚，但是，在何种程度上CI听众可以处理这样的信息在多通道刺激的情况下。拟议的实验将量化多通道频谱模式识别，多通道的时间模式识别，和多通道的频谱-时间的相互作用，在CI听众在竞争，波动的掩蔽。将探索新的刺激方法，如电流引导虚拟通道刺激，以及更集中的刺激模式的影响。结果将提供一个跨通道的相互作用，在复杂的，动态的电刺激的作用。与此同时，音素识别，性别识别和语音语调识别的措施，将在安静和竞争的噪音。将这些结果与心理物理学实验的结果进行比较，将深入了解电刺激在现实听力情况下对语音识别至关重要的那些方面。结果不仅会产生重要的基本理解复杂的听觉处理的CI听众，但他们也将适用于，在更广泛的意义上，复杂的刺激听觉处理的听力受损和听力正常的听众。拟议的工作的临床相关性是，研究结果将有助于临床评估工具和新的语音处理器的设计，为未来的听觉假体的发展。

DESCRIPTION (provided by applicant): Cochlear implants (CIs) successfully deliver auditory information to the severely hearing impaired and the profoundly deaf. However, they do not succeed in noisy backgrounds, or in the presence of competing speakers. While research has shown that the brain can learn to adapt to adverse listening conditions using top-down processing, learning and top-down mechanisms can only help to a limited extent when the information transmitted to the auditory system is severely degraded. The long-term goal of our work is to uncover basic mechanisms underlying CI listeners' auditory sensitivity, and to relate these findings to their speech perception with the device. It is increasingly apparent that, to improve sound quality, speaker recognition, source segregation, and listening in noise, CIs will need to provide fine-grained information about the speech spectrum. It is unclear, however, to what extent CI listeners can process such information in a multi-channel stimulation context. Proposed experiments will quantify multi-channel spectral pattern recognition, multi-channel temporal pattern recognition, and multi-channel spectro-temporal interactions in CI listeners in the presence of competing, fluctuating maskers. Novel stimulation methods, such as current-steered virtual channel stimulation, will be explored, as will effects of more focused stimulation mode. Results will provide a view of the role of across-channel interactions in complex, dynamic electrical stimuli. In parallel, measures of phoneme recognition, gender recognition, and speech intonation recognition will be made, both in quiet and in competing noise. A comparison of these results to the results obtained from the psychophysical experiments will yield insight into those aspects of electrical stimulation that are critical for speech recognition in realistic listening situations. The results will not only yield important fundamental understanding of complex auditory processing by CI listeners, but they will also apply, in a broader sense, to auditory processing of complex stimuli by hearing-impaired and normal hearing listeners. The clinical relevance of the proposed work is that the findings will contribute to the development of clinical assessment tools and new speech processor designs for future auditory prostheses.