Structure and function of the elastic fiber of the frog tympanic membrane: a multi-scale study

The ear is a complex biomechanical system dedicated to sound perception, even though part of the auditory function is in the central nervous system. The coupling between the two middle ear cavities has an effect on the directivity of the eardrum, which acts as a pressure difference sensor. We aim at identifying and quantifying in detail the tympanum structures related to sound perception. This includes the cartilaginous link between the tympanic membrane, the tympanic ring and stapes, the layer of membrane, and the collagen fiber distribution and muscular cells. We will use propagation based nano holotomography as a basis for the construction of a high-resolution three-dimensional dataset. Such 3D models and comparisons between data obtained for 10 samples of species varying in their frequency response should enable the understanding of the biomechanical basis of hearing very high frequency sounds.

耳朵是一套专司声音感知的复杂生物力学系统，尽管听觉功能的部分环节位于中枢神经系统内。中耳两腔之间的耦合作用会对作为压差传感器的鼓膜的指向性产生影响。本研究旨在精准识别并量化与声音感知相关的鼓膜结构，具体涵盖鼓膜、鼓环与镫骨之间的软骨连接结构、鼓膜各层组织，以及胶原纤维分布与肌细胞特征。我们将采用基于传播的纳米全息层析成像（propagation-based nano holotomography）为技术基础，构建高分辨率三维数据集。通过构建此类三维模型并对10个具备不同频率响应特性的物种样本的所获数据开展对比分析，有望阐明极高频声音感知的生物力学机制。