The ecological significance of extended high-frequency hearing in humans

世界卫生组织报告称，近5亿人患有致残性听力损失 全世界。听力损失通常在标准测听频率范围内测量，250至8,000赫兹。 然而，年轻、健康的人类听力频率范围延伸到大约20,000赫兹。扩展高- 频率听力损失(&gt；8,000赫兹)在临床上很少被评估，但它是一种广泛的、自然的、与年龄相关的疾病 早在成年初期就开始的状况。目前还不清楚高频扩展到了什么程度 听力损失会影响日常功能。这项建议评估了扩展高频的生态价值 在现实环境中，听觉用于言语感知和空间感知，这将包括空间分离 在混响条件下具有不同头部方向的说话者。有三个具体目标。目标1将 生成高保真多方向消声语音数据库，具有代表性的成年本地人队列 说美式英语的人。这个数据库被设计用于语音感知实验和 将公之于众。整个人类听觉范围内的语音光谱能量将是 检查了说话者周围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知觉和空间知觉的影响 听力正常的听众输出到16千赫。这些实验是基于我们最近观察到的 语音中扩展的高频为语音中的语音识别提供了好处。我们将确定 这种好处在现实环境中的大小以及造成这种好处的因素。目标3将测试 扩展高频对言语知觉和空间知觉的自然丧失。自然损失的形式 这将被研究包括延长高频下的听力损失和戴面罩。 (面具)说话者。拟议的研究将确定扩展高频对以下方面的生态效用 语音交流。将获得关于高频听力损失的延长程度的有价值的见解 影响听力正常的听众的日常生活。预计拟议研究的结果 将有助于正在进行的努力，以(1)改善听力损失的临床测量和(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.