The Anatomical Basis of Human Tongue Biomechanics

描述(申请人提供)：人类语言有什么特别之处？ 这使得它能够执行人类语言独有的动作 吞下去吗？舌头的生物力学依赖于它的解剖学， 人类舌头解剖学的一些最基本的事实是未知的。它是 假设人类的舌头包含与 人类说话和吞咽的动作。研究这一解剖结构将增加 我们对舌头运动的理解；提供了一个标准化的基线， 比较病理情况，并提供所需的详细信息 舌头外科手术的进展，包括移植。这个 人类的舌头给解剖学家带来了巨大的挑战：小肌肉 以复杂方式交织在一起的群体在技术上很难追踪；它 通常很难在组织切片中识别特定的肌肉； 许多在动物研究中常规使用的技术不能用于人类工作岗位 死亡组织。然而，根据研究人类喉咙的经验，一种 提出了系统的方法和各种技术，这些技术都已经 在前期工作中测试成功。舌头解剖学将同时 在大体解剖、显微和分子水平上进行研究 方法：1)舌部高分辨率磁共振显微成像 组织来研究3D结构细节；2)Sihler‘s染色，这是一种 将整个舌头样本渲染为半透明，同时对神经进行跟踪 肌群的供应和轮廓；3)全舌连续切断术 然后染色以显示肌肉结构的细节并插入到 结缔组织；4)肌肉纤维的显微解剖，然后银和 乙酰胆碱酯酶染色以研究肌肉纤维的大小和形状的细节， 运动终板类型和终末轴突分支；5)肌原纤维ATPase，至 对每一块肌肉的肌纤维进行分类；6)免疫组织化学，以确定 舌肌肌球蛋白重链(MHC)；7)免疫电泳法 免疫印迹，以确认免疫组织化学。前期工作已完成 支持人类舌头中存在专门的解剖学。Certaln 肌肉的大小和位置与其他肌肉相比有很大的不同 哺乳动物的舌头。例如，颧舌肌就大大增大了。 下部纵轴相对较小。此外，人类 舌肌有不同寻常的内部结构：有些似乎是 被分割成一系列排列的较小的肌肉纤维组。在……里面 上纵肌的初步工作表明，这些肌肉 隔间令人惊讶地短，肌肉纤维 在复杂的网络中相互连接。总体而言，人类的舌头拥有最高 在哺乳动物的舌头中，还没有报道过慢抽动肌肉纤维的比例， 它们以倾斜的方式排列，中间的比例更高 在舌根上。在这些缓慢的肌肉纤维中，有大量的 慢速紧张性肌肉纤维，是一种极其罕见的肌肉纤维类型，具有独特的 收缩特性。总而言之，关于人类的信息匮乏 舌头似乎提供了一个机会来增加我们对 言语和吞咽的特殊性质及其病理生理学 吞咽困难和构音障碍。

DESCRIPTION (provided by applicant): What is special about the human tongue that allows it to perform the movements that are unique to human speech and swallowing? The biomechanics of the tongue are dependent on its anatomy, and some of the most basic facts of human tongue anatomy are unknown. It is hypothesized that the human tongue contains specialized anatomy related to the movements of human speech and swallowing. Studying this anatomy will increase our understanding of tongue movements; provide a normative baseline from which to compare pathological conditions, and provide the detail required for progress in surgical procedures on the tongue, including transplantation. The human tongue presents formidable challenges for the anatomist: the small muscle groups that interweave in complex ways are technically difficult to trace; it is often difficult to identify specific muscles in histological sections; and many techniques routinely used in animal studies cannot be used on human post mortem tissue. However, based on experience studying the human larynx, a systematic approach is proposed with a variety of techniques that have all been successfully tested in the preliminary work. Tongue anatomy will simultaneously be studied on the gross anatomical, microscopic and molecular level using the following methods: 1) high-resolution magnetic resonance microscopy of tongue tissue to study 3-D structural detail; 2) Sihler's stain, a process that renders whole tongue specimens translucent while counterstalning the nerve supply and outlines of muscle groups; 3) serial sectioning of whole tongues followed by staining to show details of muscle structure and insertion into connective tissue; 4) micro dissection of muscle fibers followed by silver and acetylcholinesterase staining to study details of muscle fiber size and shape, motor endplate types, and terminal axon branching; 5) myofibrillar ATPase, to type the muscle fibers of each muscle; 6) immunohistochemistry, to identify the myosin heavy chain (MHC) within tongue muscles; and 7) immunoelectrophoresis and immunoblotting, to confirm the immunohistochemistry. Preliminary work has supported the presence of specialized anatomy in the human tongue. Certaln muscles are significantly different in size and position when compared to other mammalian tongues. The genioglossus muscle, for example, is greatly enlarged while the inferior longitudinal is comparatively smaller. In addition, human tongue muscles have unusual internal structure: some appear to be compartmentalized into smaller groups of muscle fibers arranged in series. In the superior longitudinal muscle preliminary work suggests that these muscle compartments are surprisingly short and that the muscle fibers are interconnected in complex webs. Overall, the human tongue has the highest proportion of slow twitch muscle fibers yet reported in any mammalian tongue, and these are arranged in a gradient with the higher proportions found medially and in the tongue base. Among these slow muscle fibers are large numbers of slow tonic muscle fibers, an extremely rare type of muscle fiber with unique contractile properties. In summary, the dearth of information about the human tongue appears to offer an opportunity to increase our understanding of the special nature of speech and swallowing as well as the pathophysiology of dysphagia and dysarthria.