Lockeed Martin, 3375 Koapaka Street, Suite I-500, Honolulu, Hawaii 96819, USA.
J Acoust Soc Am. 2011 Nov;130(5):3107-14. doi: 10.1121/1.3644912.
The auditory filter shape of delphinid odontocetes was previously considered to be typically mammalian constant-quality in which filter bandwidths increase proportionally with frequency. Recent studies with porpoises demonstrate constant-bandwidth portions of the auditory filter. The critical ratios for a bottlenose dolphin were measured between 40 and 120 kHz by behaviorally determining the subject's ability to detect pure tones in the presence of white noise. Critical ratios as a function of frequency were constant, indicating the auditory filter acts as a constant-bandwidth system in this frequency range. Re-analysis of past studies supports these findings, and suggests the delphinid auditory system is best characterized as a constant-Q system below 40 kHz and a constant-bandwidth-like system between 40 kHz and 120 kHz before returning to a constant Q pattern at the highest frequencies.
海豚科齿鲸的听觉滤波器形状以前被认为是典型的哺乳动物恒定品质，其中滤波器带宽与频率成比例增加。最近对海豚的研究表明，听觉滤波器具有恒定带宽部分。通过行为学方法确定主体在白噪声存在下检测纯音的能力，在 40 至 120 kHz 之间测量了宽吻海豚的临界比值。作为频率函数的临界比值是恒定的，这表明听觉滤波器在该频率范围内充当恒定带宽系统。对过去研究的重新分析支持了这些发现，并表明海豚听觉系统在低于 40 kHz 的频率下最好被描述为恒定 Q 系统，在 40 至 120 kHz 之间为类似于恒定带宽的系统，然后在最高频率下恢复到恒定 Q 模式。
