Doctoral Dissertation Research: Assessing the chewing function of the hyoid bone and the suprahyoid muscles in primates

舌骨是一个小的u形骨，位于舌头的底部和喉部（喉）的顶部。这种骨骼的形状和肌肉附着对于舌头运动、咀嚼、吞咽和发声都很重要。这篇博士论文研究了舌骨的形状、位置和肌肉附着之间的关系，以确定舌骨在灵长类动物进食中的作用。这项工作使研究人员了解了舌骨的功能，这可能会导致人类语言和吞咽障碍的新治疗方法的形成。这项工作还通过支持本科生和研究生培训以及创建可用于针对K-12学生和公众的科学推广项目的公开可用的microCT扫描数据集来培养STEM人才。总的来说，这项工作准备教育公众科学和进化的概念，建立和鼓励未来的研究人员，并增加了目前对头部和颈部解剖和功能的理解，这具有重要的生物医学意义。 舌骨和连接它到头骨的肌肉（即，舌骨上肌）是咀嚼、吞咽、舌头操纵和发声的中心。这些行为，特别是那些涉及喂养，如何影响舌骨解剖是不为人知的，因为以前的工作集中在发声作为舌骨形状的驱动因素。在进食过程中舌骨几乎处于恒定的运动状态，在吞咽过程中舌骨上肌将舌骨拉向口腔。本研究的目的是通过评估灵长类动物舌骨形状和位置的变化及其与舌骨上肌和头骨的关系来量化吞咽的影响。本计画利用微电脑断层扫描及碘染色的方法，将舌骨器官沿着进行三维形状分析，以探讨舌骨、颅骨与肌肉组织之间的关系。此外，这项工作分析了这些关系如何在两种密切相关的灵长类动物的生长和发育过程中发生变化，这些灵长类动物在饮食方面存在显着差异。在这样做的过程中，这项工作可以提供有价值的见解人类舌骨的形状和功能的演变，并把人类舌骨解剖到灵长类舌骨变异的更广泛的背景下，这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

The hyoid is a small u-shaped bone that sits at the base of the tongue and the top of the larynx (voice box). The shape and muscular attachments to this bone are important for tongue movements, chewing, swallowing, and vocalization. This doctoral dissertation research investigates the relationship between shape, position, and muscular attachment of the hyoid to determine the role of this bone in feeding across primates. This work informs researchers about the function of the hyoid, which may result in the formation of novel treatments for speech and swallowing disorders in humans. This work also builds STEM talent by supporting undergraduate and graduate training and creating an openly available dataset of microCT scans that can be used in scientific outreach projects aimed at K-12 students and the public. Overall, this work is poised to educate the public on scientific and evolutionary concepts, build and encourage future researchers, and add to the current understanding of head and neck anatomy and function, which has important biomedical implications. The hyoid and the muscles that connect it to the skull (i.e., the suprahyoid muscles), are central to chewing, swallowing, tongue manipulation, and vocalization. How these behaviors, specifically those involved in feeding, affect hyoid anatomy is not well known as previous work has focused on vocalization as a driving factor for hyoid shape. The hyoid is in near-constant motion during feeding and is pulled toward the oral cavity during swallowing by the suprahyoid muscles. The goal of this research is to quantify the impact of swallowing by evaluating variation in hyoid shape and position and their relationship to the suprahyoid muscles and skull in primates. This project utilizes microCT scans and iodine staining methods to visualize the hyoid apparatus along with 3D shape analyses to investigate the relationships between the hyoid, skull, and musculature. Additionally, this work analyzes how these relationships change throughout growth and development in two closely related species of primates with notable differences in diet. In doing so, this work can provide valuable insights into the evolution of human hyoid shape and function and put human hyoid anatomy into the broader context of primate hyoid variation.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.