The ecological significance of extended high-frequency hearing in humans

世界卫生组织报告说，近5亿人患有致残性听力损失， 国际吧听力损失通常在标准听力频率范围内测量，250至8，000 Hz。 然而，年轻、健康的人的听觉频率范围扩展到大约20，000 Hz。延伸高- 频率听力损失（> 8，000 Hz）在临床上很少评估，但它是一种广泛的，自然的，与年龄有关的 早在青年期就开始的病症。目前尚不清楚在多大程度上扩展了高频 听力损失影响日常生活。本提案评估了延伸高频的生态价值 听力的言语感知和空间意识在现实的设置，其中将包括空间上分离 在混响条件下具有不同头部方向的讲话者。有三个具体目标。目标1将 生成高保真度多方向无回声语音数据库，该数据库具有成年本地人的代表性群组 说美式英语的人该数据库被设计用于语音感知实验， 将被公开。在人类听觉的整个范围内的语音频谱能量将是 检查，以及向周围的谈话者不同方向的语音辐射的性质。目标2将 测试扩展高频的模拟损失对语音感知和空间意识的影响， 听力正常的听众，16 kHz。这些实验是基于我们最近的观察， 语音中扩展的高频为语音中语音识别提供了益处。康贝特人将以 目标3将测试在现实环境中这种益处的大小以及造成这种益处的因素。 在言语感知和空间意识上的扩展高频的自然损失。自然损失的形式 将被研究的包括在扩展高频下的听力损失和戴面罩 （面具）说话的人。拟议的研究将建立生态效用的扩展高频率， 言语交流将获得有价值的见解，如何延长高频听力损失 影响听力正常的听众的日常生活。预计拟议研究的结果 将有助于（1）改善听力损失的临床措施和（2）改善助听器 加工技术

The World Health Organization reports that nearly a half billion people suffer from a disabling hearing loss worldwide. Hearing loss is typically measured in the standard audiometric frequency range, 250 to 8,000 Hz. However, the young, healthy human frequency range of hearing extends to about 20,000 Hz. Extended high- frequency hearing loss (>8,000 Hz) is rarely assessed in the clinic but is a widespread, natural, age-related condition that begins as early as young adulthood. It is unknown to what extent extended high-frequency hearing loss affects daily functioning. This proposal assesses the ecological value of extended high-frequency hearing for speech perception and spatial awareness in realistic settings, which will include spatially separated talkers having different head orientations in reverberant conditions. There are three specific aims. Aim 1 will generate a high-fidelity multi-directional anechoic speech database with a representative cohort of adult native speakers of American English. This database is designed to be used for speech perception experiments and will be made publicly available. Speech spectral energy across the full range of human hearing will be examined, as well as the nature of speech radiation toward different directions around the talkers. Aim 2 will test the effect of simulated loss of extended high frequencies on speech perception and spatial awareness for listeners with normal hearing out to 16 kHz. These experiments are based on our recent observation that extended high frequencies in speech provide a benefit for speech-in-speech recognition. We will determine the magnitude of this benefit in realistic settings and the factors responsible for it. Aim 3 will test the effect of natural loss of extended high frequencies on speech perception and spatial awareness. Forms of natural loss that will be studied include hearing loss at extended high frequencies and the wearing of face coverings (masks) by talkers. The proposed studies will establish the ecological utility of extended high frequencies for speech communication. Valuable insight will be gained as to how extended high-frequency hearing loss impacts daily living for otherwise normal-hearing listeners. It is expected that results of the proposed studies will aid in ongoing efforts to (1) improve clinical measures of hearing loss and (2) improve hearing-aid processing techniques.