Differences in Swallow Mechanics in Infants

描述（由申请人提供）：吞咽需要协调 大量的肌肉;这种复杂性部分是由于需要气道 保护在上一个资助期间，我们增加了对 肌肉活动和口咽运动学在婴儿吞咽。然而，在这方面， 大多数肌肉在排空谷和 通过喉口或自然刺激的食团输送 在成熟过程中， 明白我们的初步数据表明，两种不同的途径， 存在运动，在会厌/喉开口周围（新生儿） 或以其故，或以其故，或以其故。然而，过渡的时机，从 一条路径到另一条路径以及运动学或马达中的相关变化 模式是未知的。去脑猪是研究 因为吞咽的这个阶段可以被隔离， 实验性的我们建议将我们现有的技术应用于这个模型 和完整的动物，以回答以下问题。什么自然 刺激启动谷排空，它们在成熟过程中改变吗？ 在胃谷排空过程中， 肌肉激活的顺序和幅度是否会改变 在谷排空期间，丸剂改变了运动模式， 随着发展时间的变化？会厌运动是否由以下原因引起：（i） 直接肌肉收缩;（ii）喉的其余部分的间接运动， (iii)食物对会厌的机械作用，或者所有的组合 三个？目前对人类吞咽困难和康复的研究严重依赖于 几项关于成年人和动物口腔功能的较早研究;这些研究 没有办法检查谷功能的个体发育， 详细对运动模式成熟的拟议研究将提供一个 针对人类婴儿吞咽困难的治疗策略的重要基线。

DESCRIPTION (provided by applicant): Swallowing requires the coordination of a large number of muscles; this complexity arises partly from the need for airway protection. In the previous funding period, we added to the understanding of muscle activity and oropharyngeal kinematics in infant deglutition. However, the role of the majority of muscles during emptying of the valleculae and in the transport of the bolus past the laryngeal opening or the natural stimuli that initiate the emptying of the valleculae over maturation is not well understood. Our preliminary data suggest that two distinct pathways of bolus movement exist, either around the epiglottis/laryngeal opening (in the newborn) or over it (by the age of weaning). However the timing of the transition, from one path to the other and the associated changes in the kinematics or motor patterns, are unknown. The decerebrate pig is an excellent model for studying vallecular emptying because this phase of the swallow can be isolated experimentally. We propose to apply our existing techniques both to this model and to intact animals, in order to answer the following questions. What natural stimuli initiate vallecular emptying, and do they change during maturation? What is the pattern of muscle activity during vallecular emptying in terms of the order and amplitude of muscle activation? Does change in the consistency of the bolus alter the motor pattern during vallecular emptying, and does this change over developmental time? Does epiglottal movement result from: (i) direct muscle contraction; (ii) indirect movement of the rest of the larynx, (iii) the mechanical action of food on the epiglottis, or a combination of all three? Current studies of human dysphagia and rehabilitation rely heavily on several older studies of oral function in adult man and animal; these studies did not have the means to examine the ontogeny of vallecular function in detail. The proposed study of the maturation of motor patterns will provide an important baseline for treatment strategies aimed at human infant dysphagia.