Effects of aging on swallowing physiology with transient cortical disruption

描述（由申请人提供）：老年人不成比例地受到吞咽障碍或吞咽困难的影响，这种情况可能导致发病率和死亡率增加。吞咽起始延迟是神经源性吞咽困难的常见和破坏性病理生理学，并且也由健康的老年人经历，使得功能性吞咽不太安全。以前，我们已经表明，健康的老年人有显着延迟吞咽发作以及增加初级感觉运动皮层（SMI）的神经激活，在年轻人中不存在的现象。然而，目前尚不清楚SMI激活的差异是否与吞咽启动延迟或其随年龄增长的后果有关。该提案的目标是：（1）了解SMI对吞咽启动的功能作用;（2）描述衰老对吞咽启动的影响，并伴有短暂的皮质破坏;（3）Humbert博士获得神经科学、感觉运动控制和衰老吞咽生理学方面的专门培训。总体假设是SMI的短暂中断将在年轻人和老年人的吞咽启动中产生可测量的延迟，但老年人将具有更明显的缺陷。我们将应用单脉冲经颅磁刺激（TMS），以双边SMI喉代表与同时视频荧光透视和肌电图（EMG）在吞咽过程中，在不同的时间间隔，以检查吞咽发作的变化在健康的年轻人和老年人。这项研究将确定皮层区域是否参与启动吞咽以及时机对这一功能的重要性。我们还将能够通过测试年轻人和老年人来确定老年人是否具有抵抗SMI中断的能力下降。这项研究的结果是重要的，因为老年人群更容易因神经功能缺损（如阿尔茨海默病、中风和帕金森病）而发生吞咽困难。这项研究所获得的知识将成为制定科学合理的战略，以减少这一负担我们社会的共同卫生保健问题的基础。相关性（参见说明）：这项调查与公共卫生有关，因为它将确定老年人是否具有抵抗大脑中断的能力下降，导致吞咽延迟。这一点很重要，因为老年人更容易因阿尔茨海默病、中风和帕金森病而出现吞咽障碍。这项研究中获得的知识将有助于制定干预措施，以减少这一负担我们社会的常见卫生保健问题。

DESCRIPTION (provided by applicant): Older adults are disproportionately affected by swallowing impairment, or dysphagia, a condition that can lead to increased morbidity and death. Delayed initiation of swallowing is a common and devastating pathophysiology of neurogenic dysphagia, and is also experienced by healthy older adults, making functional swallowing less safe. Previously we have shown that healthy older adults have significantly delayed swallowing onset as well as increased neural activation in the primary sensory-motor cortex (SMI), a phenomenon absent in younger adults. However, it is still not known if differences in activation of SMI are responsible for delays in swallowing initiation or its consequence with advancing age. The goals of this proposal are; (1) to understand the functional role of SMI on swallowing initiation; (2) to characterize the effect of aging on swallowing initiation with transient cortical disruption; and, (3) for Dr. Humbert to obtain specialized training in neuroscience, sensory-motor control, and aging swallowing physiology. The overall hypothesis is that transient disruption of SMI will produce measurable delays in swallowing initiation in young and old adults, but older adults will have more pronounced deficits. We will apply single-pulse transcranial magnetic stimulation (TMS) to the bilateral SMI laryngeal representation with concurrent video fluoroscopy and electromyography (EMG) during swallowing at various temporal intervals to examine changes in swallowing onset in healthy young and old adults. This investigation will determine whether cortical areas are involved in initiating swallowing as well as the importance of timing on this function. We will also be able to determine whether older adults have a decreased ability to counteract the disruptions to SMI by testing young and old adults. The results from this proposed investigation is significant because the geriatric population is more prone to developing dysphagia due to neurological impairment such as Alzheimer's disease, stroke, and Parkinson's disease. The knowledge gained in this study will become the foundation to develop scientifically sound strategies to reduce this common health care problem that burdens our society. RELEVANCE (See instructions): This investigation is relevant to public health because it will determine whether older adults have a decreased ability to counteract disruptions to the brain, causing delays in swallowing. This is significant because the geriatric population is more likely to develop swallowing impairment due to Alzheimer's disease, stroke, and Parkinson's disease. The knowledge gained in this study will help to develop interventions to reduce this common health care problem that burdens our society.