過去研究指出初級聽覺皮質處理聲音頻率的特性，是活化的皮質隨著音高有著依序排列的現象，初級聽覺皮質不同的區塊對映著不同音高的反應，我們希望藉由混頻聲音刺激下的強度比較，更進一步來推測聽覺皮質處理不同頻率聲音時的處理機制。故本研究將利用低溫超導量子干涉元件(Superconducting Quantum Interference Device，SQUID)組成之128通道腦磁圖儀(Magnetoencephalography，MEG)系統，來深入探討由混頻聲音刺激所造成聽覺腦磁訊號。藉由觀察磁場的等位線分佈圖(magnetic isofield contour map)及電流密度(Current Density Reconstruction，CDR)推算腦磁訊號源的結果，來分析混頻聲音刺激下所對應到大腦皮質層活化區域的差異。
受試者共十位聽力正常符合實驗需求的受試者來參加實驗。本研究實驗設計採用三種不同的混頻聲音刺激，以進行腦磁波的量測。結果顯示高頻聲音刺激活化位置越往聽覺皮質區的深層發展。從活化強度上來分析，對於第三種的混頻音經由帶通濾波劃分為兩種刺激，與單獨兩種刺激在活化強度上並沒有明顯差異，因而我們推測聽覺皮質趨向於獨立處理不同頻率的聲音。

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