用於量測頭髮部位腦電訊號之主動式梳狀乾電極之研究

Abstract

腦電訊號產生於腦部神經的活動，許多腦部疾病和人體的心理狀態可藉由腦訊號診斷而得。一般而言，腦電訊號測量使用有導電膏的傳統貼附式銀/氯化銀電極作為一個有較好訊號品質的量測方法。然而，在傳統貼附式銀/氯化銀電極使用上，患者必須經過皮膚處理以及導電膏經過長時間使用後，導電膏將會硬化導致訊號衰減失真。因此本論文發展出新型主動式梳狀乾電極用於長時間的臨床使用。此主動式梳狀乾電極可不需要導電膏和皮膚處理而直接量測腦電訊號。梳狀造型可直接穿過頭髮有效接觸頭皮。除此之外，此主動式梳狀乾電極可避免共模拒斥比的下降。腦訊號品質的相關性和運動干擾的情況也在本論文中被測試。最後， 波和穩態視覺誘發電位的實驗也在本論文中實行。實驗的結果表示此主動式梳狀乾電極可清楚的獲取腦電訊號。

Electroencephalogram(EEG) comes from the neuron activity. Brain disease and human physical condition can be detected from EEG information. In general, EEG is measured by traditional adhesive Ag/AgCl electrodes as an effective way for well EEG signal quality. However, patients should have skin preparation and the conductive gels in traditional adhesive Ag/AgCl electrodes would harden which results signal attenuation after several hours. Therefore novel active comb-shaped dry electrode has been proposed for long time EEG monitoring in clinical usage. The active comb-shaped dry electrodes can measure EEG signal directly without conductive gel and skin scrub. The comb shape can easily penetrate hair on scalp for good contact. Besides, the active comb-shaped dry electrode could avoid the reduction of common mode rejection ratio (CMRR). The correlation of signal quality and motion artifact were also tested in this study. Finally, the experiments of alpha rhythm and steady state visual evoked potential (SSVEP) were applied. The results shows that the proposed active comb-shaped dry electrode could acquire EEG signal clearly.