人腦接受到聲音刺激，造成神經元活化，因神經元的活化繼而產生電流，使用128通道腦磁儀量測其產生的磁場，再藉由磁場訊號反推出電流密度分佈區域，即可得知大腦接受刺激時，神經元活化的區域。此法因不用外加磁場，也沒有輻射的危險，用於醫學研究探討，是十分安全的儀器。
實驗主要使用一段長度300 ms、 500 Hz、73分貝的單調音讓受測者的單耳接受聲音刺激，在SQUID感測元件所量測到的人腦磁場訊號中，可以發現當聲音開始以後的100 ms附近會產生峰值，稱為N100m on-response，在聲音結束的100 ms 附近也會產生峰值，稱為N100m off-response。而128通道腦磁儀可以在毫秒的時間等級接收到磁場訊號，故擁有較佳時間的解析度。即是，腦部接收刺激訊號後，可以在毫秒的時間等級，觀察在人腦內部神經元活化的傳遞行為。
在分析上面使用一套軟體CURRY，由獨立成份分析法(independent component analysis)挑出雜訊，找出主要成份:N100m on-response、N100m off-response磁場訊號，計算電流偶極子(current dipole)的方向、位置、大小；並且反推出神經元活化區域 (source localization)。
在給予聲音刺激觀察大腦的神經傳遞行為上，能初步的得知N100m on-response以及N100m off-response二處的神經元活化區座落在聽覺皮質層上。而且經由計算出的電流偶極子也在大腦的聽覺皮質層上，細部上，可觀察出N100m on-response的電流偶極子位置會在聽覺皮質層的外層，而N100m off-response的電流偶極子則位在聽覺皮質層較深層的位置。
聲音震動傳送到內耳，再透過部分的腦幹(耳蝸核和下丘)沿著聽覺神經移動傳達到丘腦，再傳遞到大腦聽覺皮質層。研究中顯示給予左耳聲音刺激時，右腦部份的磁場訊號會最先到鋒值，左腦延遲的時間大致都在10 ms左右；然而給予右耳聲音刺激時左、右腦的延遲時間，則因人而異，主要原因應為左、右腦的不對稱性所導致。
腦磁儀這種非侵入式的量測儀器，不僅能幫助我們研究在給予刺激以後，大腦的反應行為，未來希望也能應用在醫學的檢驗測量上面。

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