Caruso Department of Otolaryngology and Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90033.
Caruso Department of Otolaryngology, University of Southern California, Los Angeles, California 90033.
Cold Spring Harb Perspect Med. 2019 Feb 1;9(2):a033498. doi: 10.1101/cshperspect.a033498.
Otoacoustic emissions (OAEs) evoked from the inner ear are the barely audible, signature byproduct of the delicate hydromechanical amplifier that evolved within its bony walls. Compared to the sounds evoked from the ears of common laboratory animals, OAEs from human ears have exceptionally long delays, typically exceeding those of cats, guinea pigs, and chinchillas by a factor of two to three. This review asks "Why are human OAE delays so long?" and recounts efforts to locate answers in the characteristics of mechanical frequency selectivity in the inner ear. The road to understanding species differences in OAE delay leads to the identification of new invariances and to the emergence of new questions.
耳声发射（OAE）是内耳产生的几乎听不见的精细水力学放大的特征副产品。与常见实验动物耳朵产生的声音相比，人类耳朵产生的 OAE 具有异常长的延迟，通常比猫、豚鼠和龙猫的延迟长两倍到三倍。这篇综述提出了“为什么人类 OAE 延迟这么长？”的问题，并回顾了在内耳机械频率选择性特征中寻找答案的努力。了解 OAE 延迟的物种差异的途径导致了新不变性的发现，并提出了新的问题。
