Yan H Y
School of Biological Sciences, University of Kentucky, Lexington 40506-0225, USA.
J Comp Physiol A. 1998 Sep;183(3):325-33. doi: 10.1007/s003590050259.
Fish hearing specialists (e.g., goldfish, holocentrids, clupeoids, mormyrids) have evolved specialized structures (e.g., Weberian ossicles, swimbladder diverticulae, gas-filled bullae) to enhance their auditory frequency range and threshold sensitivity. The inner ears of anabantoid fish are encased in membranous cranial bones and are protruded into air-filled suprabranchial chambers. This research was intended to test the hypothesis that the gas bubbles inside the suprabranchial chambers may modulate the hearing abilities of anabantoid fish because of their proximity to the membranous bone-encased inner ears. Three species of gourami (blue gourami Trichogaster trichopterus; kissing gourami Helostoma temminckii; dwarf gourami Colisa lalia) were examined. Using the auditory brainstem response recording technique, baseline audiograms tested at 300, 500, 800, 1500, 2500, 4000 Hz were obtained. The air bubbles in the suprabranchial chambers were replaced by water, and the audiograms were remeasured. Thresholds were elevated in all three species. When three blue gouramis were allowed to replenish air into the suprabranchial chambers their hearing abilities returned to baseline levels. These results support the hypothesis that air bubbles in the suprabranchial chambers can affect hearing abilities of gouramis by lowering the thresholds.
鱼类听力专家（如金鱼、金眼鲷、鲱形目鱼类、裸臀鱼）已经进化出专门的结构（如韦氏小骨、鳔憩室、充气大泡）来扩大其听觉频率范围并提高阈值敏感性。攀鲈科鱼类的内耳包裹在膜质颅骨中，并突出到充满空气的鳃上腔。本研究旨在验证以下假设：鳃上腔内的气泡可能因其靠近被膜质骨包裹的内耳而调节攀鲈科鱼类的听力。研究人员对三种丝足鲈（蓝曼龙Trichogaster trichopterus；接吻鲈Helostoma temminckii；矮曼龙Colisa lalia）进行了检查。使用听觉脑干反应记录技术，获得了在300、500、800、1500、2500、4000赫兹下测试的基线听力图。用注入水取代鳃上腔内的气泡，并重新测量听力图。所有三个物种的阈值均升高。当三只蓝曼龙被允许重新向鳃上腔内补充空气时，它们的听力能力恢复到基线水平。这些结果支持了以下假设：鳃上腔内的气泡可以通过降低阈值来影响丝足鲈的听力能力。
