Differences in odontocete biosonar emissions have been reported for animals with hearing loss compared to those with normal hearing. For example, some animals with high-frequency hearing loss have been observed to lower the dominant frequencies of biosonar signals to better match a reduced audible frequency range. However, these observations have been limited to only a few individuals and there has been no systematic effort to examine how animals with varying degrees of hearing loss might alter biosonar click properties. In the present study, relationships between age, biosonar click emissions, auditory evoked potentials (AEPs), and hearing bandwidth were studied in 16 bottlenose dolphins (Tursiops truncatus) of various ages and hearing capabilities. Underwater hearing thresholds were estimated by measuring steady-state AEPs to sinusoidal amplitude modulated tones at frequencies from 23 to 152 kHz. Input-output functions were generated at each tested frequency and used to calculate frequency-specific thresholds and the upper-frequency limit of hearing for each subject. Click emissions were measured during a biosonar aspect change detection task using a physical target. Relationships between hearing capabilities and the acoustic parameters of biosonar signals are described here and compared to previous experiments with fewer subjects.

中文翻译：

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海豚听力带宽对生物声纳点击发射的影响。

据报道，听力损失的动物与正常听力的动物相比，牙本质生物声纳排放有所不同。例如，已经观察到一些具有高频听力损失的动物降低了生物声纳信号的主导频率，以更好地匹配降低的可听频率范围。但是，这些观察仅限于少数几个人，还没有系统的努力来研究具有不同程度的听力损失的动物如何改变生物声纳点击特性。在本研究中，研究了16只宽吻海豚（Tursiops truncatus）的年龄，生物声纳点击发射，听觉诱发电位（AEP）和听力带宽之间的关系。）的年龄和听力能力。通过在23至152 kHz的频率下测量稳态AEP到正弦幅度调制音调来估计水下听力阈值。输入-输出函数在每个测试频率处生成，并用于计算特定于频率的阈值和每个受试者的听力上限。在生物声波方面变化检测任务中使用物理目标测量了点击发射。此处描述了听觉能力与生物声纳信号的声学参数之间的关系，并将其与先前实验较少的对象进行了比较。