摘要
人類的眼球運動是經由中樞神經系統，包括大腦、小腦、腦幹等相互配合而完成，因此對於中樞神經系統受損或病變、退化的患者，其所產生的眼球運動將有異於正常人，巴金森氏症的患者即為一例。
根據先前的研究發現，傳統的量化參數並無法完整的描述跳視的動態過程，而藉由針對跳視整體的軌跡作描述，可以得到比較理想的量化方式。因此本研究的目的即在於對於跳視速度的波形作更進一步的探討。
有些學者提出，跳視眼球運動速度波形的加速時間幾乎不隨振幅而改變，而減速時間會隨著振幅的增加而有延長的趨勢，但另外有學者提出，雖然減速時間與運動週期與振幅呈一線性的關係，加速時間仍會隨著振幅的增加而增加，而由我們模擬出的資料顯示，加速時間在振幅小於40度時會有增加的趨勢，然後即趨近飽和。
在對於跳視速度波形加速相與減速相的研究中，我們發現在振幅變大時，減速相會有比加速項更為明顯的變化。而與加速與減速時間相較之下，加速與減速振幅有著較高的線性相關度與較小的變異性，這表示跳視系統有一自我調控的功能，能使跳視的機制有最好的效能。
另外在本研究中，我們利用了另一可用來描述峰值速度與動作區間的乘積與其振幅之間關係的方程式(有理冪函數)，研究目的即在計算出在加速相及減速相中形狀參數的值，並探究其在描述不同群組之跳視速度波形之效果。而由實驗結果顯示，利用我們新提出之參數，在針對病患與正常人的分析裡比起傳統上的參數，在不同群組之間可以得到更明顯的區別。
從上所述，在本研究中所得到的結果在未來將可作為另一種分析跳視眼球運動的方式以及作為醫師在臨床診斷上的參考依據。

ABSTRACT
The control of eye movements is composed of the complicated process of central nervous system (CNS) through the coordination of cerebral, cerelellum, and brain stem, etc. For patients suffer from CNS lesion, the pathological changes or degeneration will produce eye movements disorders. Patients of Parkinson’s disease would be one of them.
The previous study showed the traditional parameters can not describe the whole saccadic dynamics, and by delineating the trajectory of saccade, a better way in quantitative analysis of saccadic dynamics will be obtained. The goals of this study were to investigate the velocity profile of saccade eye movements.
Some investigators argued that the acceleration time of saccadic velocity profiles was almost unchanged for different amplitudes, while the deceleration phase increased with amplitude. Other studies, however, demonstrated that the acceleration time was significantly increased, although both deceleration time and saccadic duration against amplitude demonstrated linear relationship. Simulation data also displayed the acceleration time increased with amplitude for amplitudes below 40o, in which saturation appeared for greater amplitudes.
According to the investigation of the acceleration and deceleration phase of saccadic velocity profile, it is found that deceleration phase will be changed more significantly than acceleration phase as saccadic amplitude increases. Comparing with acceleration and deceleration time, acceleration and deceleration amplitude seem to have higher correlation coefficient and less variance, and this means there is a modulating mechanism in ocular plane, which gives the best efficiency to saccade eye movement.
We propose an equation which can represent the linear relation between product of peak velocity and duration against amplitude (rational power function). Another goal of this study were to evaluate order n of acceleration and deceleration phases of the velocity profiles, which are relating to the profile curvature. The results show that power rational function is more efficient in delineating the dynamics of the velocity in normal subjects and patients. The result might be valuable in diagnosis and able to be proposed as an alternative way in quantitative analysis of saccadic dynamics.

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