Punacha Shreyas, Huang Kevin, Arce-McShane Fritzie I
Department of Oral Health Sciences, School of Dentistry, University of Washington, Seattle, WA, USA.
Division of Neuroscience, Washington National Primate Research Center, University of Washington, Seattle, WA, USA.
bioRxiv. 2024 Aug 3:2024.07.31.605680. doi: 10.1101/2024.07.31.605680.
Several age-related oral health problems have been associated with neurodegenerative diseases such as Alzheimer's Disease (AD), yet how oromotor dysfunction in healthy aging differ from those found in pathological aging is still unknown. This is partly because changes in the cortical and biomechanical ("neuromechanical") control of oromotor behavior in healthy aging are poorly understood. To this end, we investigated the natural feeding behavior of young and aged rhesus macaques (Macaca mulatta) to understand the age-related differences in tongue and jaw kinematics. We tracked tongue and jaw movements in 3 using high-resolution biplanar videoradiography and X-ray Reconstruction of Moving Morphology (XROMM). Older subjects exhibited a reduced stereotypy in tongue movements during chews and a greater lag in tongue movements relative to jaw movements compared to younger subjects. Overall, our findings reveal age-related changes in tongue and jaw kinematics, which may indicate impaired tongue-jaw coordination. Our results have important implications for the discovery of potential neuromechanical biomarkers for early diagnosis of AD.
一些与年龄相关的口腔健康问题已被发现与神经退行性疾病（如阿尔茨海默病，简称AD）有关，但健康老龄化过程中的口面部运动功能障碍与病理性老龄化过程中的口面部运动功能障碍有何不同，目前仍不清楚。部分原因在于，人们对健康老龄化过程中口面部运动行为的皮质和生物力学（“神经机械学”）控制变化了解甚少。为此，我们研究了年轻和老年恒河猴（猕猴）的自然进食行为，以了解舌部和颌部运动学方面与年龄相关的差异。我们使用高分辨率双平面视频放射成像和移动形态X射线重建技术（XROMM），对3只猴子的舌部和颌部运动进行了跟踪。与年轻猴子相比，老年猴子在咀嚼过程中舌部运动的刻板性降低，且舌部运动相对于颌部运动的延迟更大。总体而言，我们的研究结果揭示了舌部和颌部运动学方面与年龄相关的变化，这可能表明舌颌协调受损。我们的研究结果对于发现用于AD早期诊断的潜在神经机械学生物标志物具有重要意义。
