根據觀察，想像動作時大腦運動區的神經元活動方式，和實際動作執行下的情形非常類似，其中，最明顯的特徵就是mu波和beta波振幅的抑制。這種大腦皮層的感覺運動神經因某些特定的事件而發生的非同步或同步活化現象，稱之為event-related desynchronization/synchronization（ERD/ERS）。本篇論文主要的目的在於建構一套腦機介面系統，利用ERD的方法，判別受測者想像左右手動作時的腦電波變化。
本研究使用DSLVQ的方法找出最佳的頻帶範圍，再應用線性判別分析做形態分類。為了發展即時的腦機控制系統，我們先由受測者的腦電波特徵，訓練出受測者特有的分類器。在即時的分析上，腦機介面系統便藉由訓練出來的分類器即時判別腦電波的形態。在目前的階段，我們的方法可以達到60％~80％的判別正確率。

目 錄

中文摘要------------------------------------------------------------------------------------------------I
英文摘要-----------------------------------------------------------------------------------------------II
誌謝-----------------------------------------------------------------------------------------------------III
目錄----------------------------------------------------------------------------------------------------IV
表目錄-------------------------------------------------------------------------------------------------VI
圖目錄------------------------------------------------------------------------------------------------VII

第一章 導論 1
1.1 背景 1
1.2 相關研究 1
1.3 研究動機 3
1.4 章節安排 3

第二章 理論與方法 5
2.1 腦電波 5
2.2 實驗設備 7
2.3 腦電波分析方法 8
2.3.1 前置處理 9
2.3.2 特徵萃取 11
2.3.3 DSLVQ 12
2.3.4 ERD/ERS 15
2.3.5 線性判別分析 17
2.3.6 10×10混合交叉確認 21
第三章 實驗流程 23
3.1 腦電波錄製 23
3.2 實驗設計 24
3.3 腦機介面之訓練部分 26
3.4 受測者的有效頻帶 27
3.5 分類器的計算 28
3.6 腦機介面之回授部分 29

第四章 實驗結果 31
4.1 ERD的結果 31
4.2 最佳化頻帶 36
4.3 分類器的選擇 40
4.4 錯誤率比較與結果分析 41
4.4.1 實際動作和想像動作 42
4.4.2 固定頻帶和受測者特定頻帶 45
4.4.3 想像左右手動作和想像手腳動作 48
4.4.4 實驗次數的增加 51
4.4.5 無回授和有回授 54
4.4.6 權重向量的更新 57

第五章 結論與未來展望 62
5.1 結論 62
5.2 未來展望 63

附錄 65
參考文獻 68

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