Popov Vladimir V, Supin Alexander Ya, Wang Ding, Wang Kexiong
Institute of Ecology and Evolution, The Russian Academy of Sciences, 33 Leninsky Prosp., 119071 Moscow, Russian Federation.
J Acoust Soc Am. 2006 May;119(5 Pt 1):3173-80. doi: 10.1121/1.2184290.
Simultaneous tone-tone masking in conjunction with the envelope-following response (EFR) recording was used to obtain tuning curves in porpoises Phocoena phocoena and Neophocaena phocaenoides asiaeorientalis. The EFR was evoked by amplitude-modulated probes with a modulation rate of 1000 Hz and carrier frequencies from 22.5 to 140 kHz. Equivalent rectangular quality QERB of the obtained tuning curves varied from 8.3-8.6 at lower (22.5-32 kHz) probe frequencies to 44.8-47.4 at high (128-140 kHz) frequencies. The QERB dependence on probe frequency could be approximated by regression lines with a slope of 0.83 to 0.86 in log-log scale, which corresponded to almost frequency-proportional quality and almost constant bandwidth of 3-4 kHz. Thus, the frequency representation in the porpoise auditory system is much closer to a constant-bandwidth rather that to a constant-quality manner.
结合包络跟随反应（EFR）记录，采用同时音对音掩蔽法来获取鼠海豚（Phocoena phocoena）和东亚江豚（Neophocaena phocaenoides asiaeorientalis）的调谐曲线。EFR由调制率为1000Hz且载波频率在22.5至140kHz之间的调幅探针诱发。所获得的调谐曲线的等效矩形品质因数（QERB）在较低（22.5 - 32kHz）探针频率下为8.3 - 8.6，在较高（128 - 140kHz）频率下为44.8 - 47.4。在对数 - 对数尺度上，QERB对探针频率的依赖性可用斜率为0.83至0.86的回归线近似，这对应于几乎与频率成比例的品质以及3 - 4kHz的几乎恒定带宽。因此，鼠海豚听觉系统中的频率表征更接近恒定带宽方式而非恒定品质方式。
