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，因此有人在不同腦部病症的量測及判別上，運用眼球運動來做一參考指標。固視眼球運動被認為是由位置及速度參數來做其特性參數的眼球運動，本研究亦根據所量測得之眼球位置波形來做為分析其腦部病變之依據，以提供臨床上非侵入方式幫助醫師診斷。

本研究的受測對象可分為一般組、運動員組和病患組三個群組。64位病患其主要症狀皆為一般精神分裂症的病徵(程度不一，但皆經由醫師診斷)，並與46名一般組及5名運動員組做進行結果比對。一般組和運動員組皆為無任何視覺上的病症。三群組在量測前都有告知完整的量測過程。

經由水平偏態係數的分析顯示，在注視不同位置時的水平分量，其散佈皆呈現常態分佈，此一結果與先前本實驗室利用Camera方式的量測結果相同。所以依據此一特性吾人使用高斯分佈曲線輪廓來擬合固視之位置散佈。結果顯示由其水平方向之變異數來看，其擾動上，病患組其平均值較其他兩群組大且變異量也大之較不穩定的狀態。在不同組別的高斯分佈參數上，雖然在運動員組的平均值較一般組來得高，但是在其變異數方面則比一般組來得小，而病患組則比另外兩群組在平均數或是變異數方面都來得高。在不同群組的統計比較上，一般人跟運動員，和病患在右眼的參數上有著統計上的差異，其左眼反而無明顯差異。比較同一群組的左右眼的統計差異發現，在一般人、運動員的左右眼的比較上，在統計上，其都不具有明顯的差異，但是在比對病患的左右眼後發現，在病患的右眼跟左眼的差異上，具有統計上明顯的差異。

從上所述，發現在病患的右眼上，可能因為腦部病變的影響，而使得其高斯參數顯現出不同於其它群組，甚至是同一群組，不同眼的統計分析上具有差異性。即高斯分佈參數σ能有效地區分病患組和一般組跟運動員組的差異；在本研究中所得到的結果將可作為另一種分析固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。

Eye movement is controlled by the central nervous system (CNS) through coordination of several areas in cerebral cortex, cerebellum, and brain stem, etc. For patients suffered from CNS lesions, change or degeneration of brain function will induce eye movement disorders. Therefore, several previous studies proposed that eye movement could be used to evaluate the brain conditions.
Visual fixation has been modeled as a system consisting of a position channel and a velocity channel. In this study, we intend to analyze the patterns of visual fixation for the normal and patient subjects to find a useful parameter to provide a noninvasive method to assist the neurologists in the diagnosis of patients with brain diseases.
The subjects tested in this research were divided into three groups: normal, sportsman, and patient groups. The patient group consists of sixty-four patients who were diagnosed with schizophrenia and classified based on different degree of seriousness in syndrome by a neurologist. The results were compared with forty-six normal subjects and five subjects who are skillful in table tennis. Subjects were assured to have normal vision with or without optical correction before testing. All subjects were aware of the purpose and the testing procedure of this study.
Skewness analysis of the horizontal fixation shows that the histogram of fixation deviation can be approximated by a normal distribution, which is consistent with a previous investigation by using CCD camera measurement in our laboratory. Analysis of the standard deviation (STD) of the fixation deviation demonstrates that the patient tends to have more variance than the normal subject, which indicates the former has more unstable fixation pattern. Additionally, subjects in the sportsman group tend to have larger mean of STDe than the normal group. For the patient group, significant difference in STD was also found between the right and the left eyes. It might be caused by pathological changes in the brain for the patients. In conclusion, STD of fixation pattern is valuable in the diagnosis of patients with schizophrenia.

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