重複性顱磁刺激(repetitive transcranial magnetic stimulation)就是一項非侵入式利用電生磁、磁生電去刺激腦部、神經與肌肉等特定部位的技術，提供潛在的好處對於各種神經病學與精神病學的疾病進行治療。儘管有許多的研究及治療方式陸續發展，但目前仍缺乏線圈磁場聚焦性與強度改善的相關研究，因此，如何有效控制電磁場強度與聚焦性提高一直是重複性顱磁刺激最重要的問題。
本研究的目的在設計微小線圈應用在動物實驗上，首先，在線圈中心加入鐵核來改善磁場穿透能力大小，使用水冷卻循環系統來達到冷卻目的。再來，設計不同銅屏蔽的大小與開孔位置，並透過磁場量測平台測試磁場分佈，比較各種屏蔽設計的優缺點，達到改善聚焦性能。將此設計應用於動物實驗上，探討運動誘發電位(motor evoked potential)在沒有遮蔽的線圈與加上不同屏蔽的線圈是否能準確性的誘發，發現加上屏蔽的線圈雖然改善聚焦能力但必須要有足夠的磁通量才能誘發感應電勢。另外加上屏蔽的線圈會產生聲響而造成聽覺驚嚇反射(auditory startle reflex ) 動作誘發出MEP，因此利用分貝計來判斷，在多少分貝以上才會造成。

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive technique to stimulate the brain, nerve and muscle by electric fields that are generated from an excitation coil. rTMS offers potential benefit as a therapeutic treatment for a variety of neurological and psychiatric disorders. Although various rTMS schemes have been developed for clinical studies, there is a lack of the coil for generating localized magnetic field with enhanced intensity for rTMS in small animal. The aim of this study was to design a miniature stimulation coil for rTMS studies in small animal. First, a circular coil with iron-core for improving the penetration of the magnetic field was designed which was equipped with a water cooling apparatus to prevent from over heat. In addition, the shields of varied sizes and shapes were employed to localize the stimulation area which distribution was measured in a magnetic field recording platform using Hall effect probe controlled by 2D step motor. Our results indicated that copper plate of 1 mm thickness with proper opening can shield well and provide localized stimulation to elicit motor evoked potential (MEP). However, the shock wave generated by magnetic stimulation was enhanced during the shielding experiment which might elicit auditory startle reflex (ASR) instead of MEP. Thus, a better sound proof design to reduce the sound below 96 dB should be taken into consideration when design a shielded rTMS for small animal.

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