臺灣博碩士論文加值系統

　　人體每一部位均存在不自主且連續性的震顫，但是過大的生理性或病態性震顫，會對日常生活中精細的動作造成困擾；僅管震顫很早就被發現，但目前對改變震顫的外在因素和機制的了解仍很有限；事實上震顫本身不只是一種肢體微細振動，且其特徵受肢節間協調的影響，然而過去實驗不僅很少注意這些肢體微細動作與其交互作用，也未曾深入探討正常人與帕金森病患姿勢性與動作性震顫所反應動作控制的意義。因此本實驗的研究目的為：1.探討正常人在靜態姿勢性與動態追蹤性活動中，加重效應對多關節震顫特徵的影響；2.在靜態姿勢性與動態追蹤性活動中，比較加重效應對帕金森患者與年齡相仿正常人多關節震顫，並探究帕金森患者震顫所反應之動作協調障礙與機制。研究方法：實驗一：徵召16個正常年輕人，於慣用手上肢各肢節上(食指、手部、前臂、上臂和頸椎第七節)分別放置五個雙軸加速規，以紀錄休息時的震顫、食指三種加重(0、50和100克)的姿勢性震顫，和食指三種加重的動作性震顫(由食指0.3或0.6赫茲進行追蹤性活動過程中產生)；實驗二：徵召9位帕金森氏症患者與9位年齡相仿的正常老年人，同樣紀錄慣用手上肢各肢節上的加速規訊號，包括休息時的震顫、食指兩種加重(0和100克)的姿勢性震顫，以及食指兩種加重的動作性震顫(由肩關節0.3或0.6赫茲進行追蹤性活動過程中產生)。分析正常年輕人、帕金森氏症患者、正常老年人在加重與非加重情形下，各肢節姿勢性與動作性震顫的振幅、頻率尖峰、近似熵與相鄰肢節震顫之交互相關函數。結果：實驗一：當食指加重和進行追蹤性活動時，會引發出肢節6~8赫茲的中頻高峰，且隨食指加重增加而使中頻頻率下降。維持固定姿勢時食指加重會使肢體姿勢性震顫振幅上升，但在追蹤性活動中食指加重後反而使肢體動作性震顫振幅下降；顯示正常年輕人各肢節的震顫特徵會隨著任務不同而不同，肢體內協調因任務而改變；實驗二：外在不同任務(如加重與動態動作)下，正常人會依任務的不同而機動地調整震顫近似熵和肢節間相關性，顯示存在有任務導向之肢體內協調；帕金森氏症患者的震顫近似熵和肢節間相關性缺乏應有之任務導向變化，使得患者在肩、腕和掌指關節處的震顫振幅較正常人增加。正常人姿勢性和動作性震顫除高頻高峰(10-12赫茲)外，加重時還會出現6~8赫茲的中頻高峰；而帕金森氏症的姿勢性和動作性震顫僅出現5-7赫茲主峰頻率，且皆略高於休息性震顫(4-6赫茲)。結論：正常人在加重與追蹤性活動時會改變上肢關節僵硬度和自主性控制，作出適當的肢體內協調來減少震顫，在同樣情況下帕金森氏症因上肢關節僵硬度和自主性控制方面協調不佳使震顫劇增；帕金森氏症動作性震顫因加重而減輕，但加重可能加劇姿勢性震顫。正常人在食指加重時所新出現的中頻高峰與帕金森氏患者姿勢性和動作性震顫的主要頻率相近，推測其來源可能為增強之長迴路牽張反射所致。

　　Tremor is an involuntary micro-vibration inherent in all human portions, but exaggerated physiological or pathological tremor could be detrimental to a wide spectrum of fine movements during daily life. Despite a long history of tremor research, the key elements and mechanism that change tremors are yet to be explored. Actually, tremor is not only a microvibration but also characteristically affected by intralimb coordination between joints. However, previous researchers did not pay much attention to the interaction among these minute movements, nor realized in depth the meanings of postural and kinetic tremors between Parkinson’s disease (PD) patients and healthy people. Consequently, this study focus on the following issues: 1) how loading effects mediates the characteristics of multi-joint tremors during static postural and kinetic tracking tasks for healthy subjects, and 2) the difference of loading effects on multi-joint tremors between PD patients and age-matched healthy subjects during static postural and kinetic tracking tasks, thus exploring PD patients’ movement difficulties and possible mechanisms on intralimb coordination.
　　Methods: Experiment 1: A set of 16 healthy young people were recruited. Five dual-axis accelerometers were placed on the finger, hand, forearm, upper arm, and C7 of the dominant upper limb. Resting tremors, postural tremors imposed by three weighting loads (0, 50, and 100 grams) on the index, and kinetic tremors while performing index sinusoidal tracing tasks at 0.3 or 0.6 Hz were recorded. Experiment 2: 9 PD patients and 9 age-matched healthy seniors were recruited. Resting tremors, postural tremors imposed with 0 and 100 grams on the index, and kinetic tremors of two weightings (while performing shoulder sinusoidal tracing tasks at 0.3 or 0.6 Hz with 0 and 100 grams on the index). In both weighting and non-weighting conditions, amplitudes, frequency peaks, approximate entropy for postural and kinetic tremor in each limb segment, and cross correlation of tremors in the adjacent limb segments were analyzed.
　　Results: Experiment 1: A frequency peak in range of 6-8 Hz emerged on all limb segments for tracing task. The magnitude of frequency peak in the middle range of tremor spectrum decreased as index loading increased. Loading on the index often raised posture tremor, but reduced kinetic tremor during a tracing task. The fact clearly indicated that tremor characteristics varied with tasks, and intralimb coordination was task dependent for healthy young adults. Experiment 2: For either loading or tracing task, healthy people were capable of skillfully mediating approximate entropy and tremor correlation of neighboring limbs segments for task demands. By contrast, PD patients were lack of adjustment of tremor characteristics in the context of approximate entropy and correlation of limbs segments, but leaded to increment of tremor amplitude on patients’ shoulders, wrists, and finger joints. Besides a frequency peak of 10-12 Hz in postural and kinetic tremors, a new frequency peak of 6-8 Hz also occurred in loading condition for healthy subjects. Meanwhile, frequency peak of postural and kinetic tremors of PD patients (5-7 Hz) was larger than the resting tremor (4-6 Hz).
　　Conclusion: healthy people were able to appropriately change joint stiffness of their upper extremities to minimize tremor when proceeding tracing tasks with or without loading. Nevertheless, PD patients were not able to alter joint stiffness in response to tracing or loading resulting in atypical increase in tremor amplitude. Loading on limb segments could effectively reduce PD kinetic tremors, but conversely enhanced postural tremor. A noticeable emergence of frequency peak in the middle band of tremor spectrum of healthy people was similar to that in postural and kinetic tremors found in the PD patients. It was speculated that the frequency peak was likely e due to the enhancement of long loop stretch reflex.

中文摘要……………………………………………………I
英文摘要……………………………………………………III
誌謝…………………………………………………………VI
目錄…………………………………………………………VII
表目錄………………………………………………………IX
圖目錄…………………………………………………………X

第一章 前言…………………………………………………1
第一節 研究背景與動機……………………………………1
第二節 研究目的……………………………………………3
第三節 研究問題與假說……………………………………4
第四節 研究問題的重要性…………………………………6
第二章 文獻回顧……………………………………………7
第一節 震顫的簡介…………………………………………7
第二節 生理震顫與帕金森氏症的文獻回顧………………9
第三節 影響震顫的兩個外在變因…………………………12
第四節 上肢震顫的肢體內協調……………………………15
第三章 研究方法……………………………………………17
第一節 實驗儀器……………………………………………17
第二節 實驗儀器校正………………………………………21
第三節 受測者………………………………………………24
第四節 實驗步驟與流程……………………………………25
第五節 訊號處理……………………………………………28
第六節 統計分析……………………………………………30
第四章 結果…………………………………………………32
第一節 正常年輕人上肢多關節震顫的特徵………………32
第二節 帕金森氏症患者上肢多關節震顫的特徵…………64
第五章 討論………………………………………………101
第一節 正常年輕人上肢多關節震顫的特徵……………101
第二節 帕金森氏症患者上肢多關節震顫的特徵………111
第六章 結論………………………………………………121
第一節 臨床應用…………………………………………121
第二節 研究限制與未來發展……………………………123
第七章 參考文獻…………………………………………125
自述…………………………………………………………135

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