Role of Skin Biomechanics in Mechanoreceptor Response

描述（由申请人提供）：该项目的最终目标是获得对人类触觉的起源和机制的科学理解：灵长类动物指尖皮肤上压痕，抚摸或振动的物体的形状，柔软度和表面纹理如何由机械感受器群体编码。对于这些刺激，寻求对什么时空负荷施加在皮肤上、它们如何通过皮肤传输以及哪些机械信号由每种类型的空间分布的机械感受器群体转导的定量理解。而在以前的补助金期间的重点一直是指尖作为一个整体的机械行为，在这个建议的重点是对个别指垫脊和凹槽的力学及其对迈斯纳小体和默克尔盘位置的影响。建立在使用机器人刺激器，成像系统和计算模型在前一个赠款期间开发的理解，新的技术和实验方法将被带到承担的问题。以下列出的所有实验将在人体和猴的指垫上进行。 该提议的具体目的是（1）使用光学相干断层扫描、超声反向散射显微镜和视频显微镜获得指垫皮肤脊和凹槽的高分辨率解剖和应变图像，（2）使用定制开发的微机电传感器阵列测量物体-指脊接触界面处的压力的空间分布，（3）使用高精度触觉刺激器获得指垫皮肤和脊阻抗数据，（4）使用来自实验的数据来进一步改进指垫的高分辨率3D计算模型并执行涉及与成形和柔软物体接触的有限元模拟，和（5）使用来自所提出的生物力学和先前的神经生理学实验的结果以及真实的计算机模型来发展对皮肤生物力学在机械感受器响应中的作用的更深入的理解。这项研究的好处包括从外周神经反应的受体动力学中描绘组织力学的作用，以及最终帮助区分外周和中枢机制在体感信息处理中的作用。从临床角度来看，长期受益的一个例子是能够设计更好的测试来评估正常和受损手部的触觉，以帮助诊断、治疗和康复。另一个附带应用的例子是，在前一个赠款期间开发的超声反向散射显微镜在体内皮肤病变成像方面显示出了希望。

DESCRIPTION (provided by applicant): The ultimate goal of this project is to gain a scientific understanding of the origins and the mechanisms of human tactile sense: how shape, softness and surface texture of objects indented, stroked or vibrated on the primate fingertip skin are encoded by populations of mechanoreceptors. For these stimuli, a quantitative understanding of what spatio-temporal loads are imposed on the skin, how they are transmitted through the skin, and which mechanical signals are transduced by each type of spatially distributed mechanoreceptor populations is sought. Whereas the focus in the previous grant periods has been on the mechanical behavior of the fingertip as a whole, in this proposal the focus is on the mechanics of individual fingerpad ridges and grooves and its impact on Meissner corpuscle and Merkel disc locations. Building on the understanding gained with the use of robotic stimulators, imaging systems, and computational models developed over the previous grant period, new technologies and experimental methods will be brought to bear upon the problem. All the experiments listed below will be conducted on human and monkey fingerpads in vivo. The specific aims of this proposal are (1) to obtain high resolution anatomical and strain images of the fingerpad skin ridges and grooves using Optical Coherance Tomography, Ultrasound Backscatter Microscopy, and Video microscopy, (2) to measure the spatial distribution of pressure at the object-finger ridge contact interface using custom developed micro-electromechanical sensor arrays, (3) to obtain fingerpad skin and ridge impedance data using a high precision tactile stimulator, (4) to use the data from experiments to further improve high resolution 3D computational models of the fingerpad and perform finite element simulations involving contact with shaped and soft objects, and (5) to use the results from proposed biomechanical and previous neurophysiological experiments together with realistic computer models to develop a deeper understanding of the role of skin biomechanics in mechanoreceptor response. The benefits of this research include the delineation of the role of tissue mechanics from receptor dynamics in peripheral neural response, as well as eventually aiding the differentiation of the roles of peripheral and central mechanisms in somatosensory information processing. One example of a long-term benefit from a clinical standpoint will be the ability to design better tests for the evaluation of tactile sensibility of normal and impaired hands to aid diagnosis, treatment and rehabilitation. Another example of a spin-off application is that the Ultrasound Backscatter Microscope developed in the previous grant period has shown promise in imaging skin lesions in vivo.