Palghat Udayashankar Arun, Kössl Manfred, Nowotny Manuela
AK Neurobiologie und Biosensorik, Institute for Cell Biology and Neuroscience, Goethe University, Frankfurt/Main, Germany.
PLoS One. 2014 Jan 21;9(1):e86090. doi: 10.1371/journal.pone.0086090. eCollection 2014.
Travelling waves are the physical basis of frequency discrimination in many vertebrate and invertebrate taxa, including mammals, birds, and some insects. In bushcrickets (Tettigoniidae), the crista acustica is the hearing organ that has been shown to use sound-induced travelling waves. Up to now, data on mechanical characteristics of sound-induced travelling waves were only available along the longitudinal (proximal-distal) direction. In this study, we use laser Doppler vibrometry to investigate in-vivo radial (anterior-posterior) features of travelling waves in the tropical bushcricket Mecopoda elongata. Our results demonstrate that the maximum of sound-induced travelling wave amplitude response is always shifted towards the anterior part of the crista acustica. This lateralization of the travelling wave response induces a tilt in the motion of the crista acustica, which presumably optimizes sensory transduction by exerting a shear motion on the sensory cilia in this hearing organ.
行波是许多脊椎动物和无脊椎动物类群（包括哺乳动物、鸟类和一些昆虫）频率辨别能力的物理基础。在螽斯（螽斯科）中，听脊是听觉器官，已被证明利用声音诱发的行波。到目前为止，关于声音诱发行波的力学特性的数据仅在纵向（近端-远端）方向上可得。在本研究中，我们使用激光多普勒测振仪来研究热带螽斯长瓣草螽中行波的体内径向（前后）特征。我们的结果表明，声音诱发的行波振幅响应的最大值总是朝着听脊的前部移动。行波响应的这种侧向化导致听脊运动发生倾斜，这可能通过在这个听觉器官的感觉纤毛上施加剪切运动来优化感觉转导。
