靜息態功能性磁振造影(rsfMRI)可以用來量測神經元活動所引發的血氧濃度相依(BOLD)對比的變化，而在過去研究中也找到多種由不同腦區所組成的靜息態網路，當人處於休息狀態且沒有特定任務或刺激時，靜息態網路區域的神經元活動會特別活躍，其中預設模式網路(DMN)被證實為穩定且在大部分人腦中皆可以找到的靜息態網路，而腦區內的神經元活動與代謝物關係密切，因此論文中對於預設模式網路與非預設模式網路之間的代謝物濃度是否有所差異進行分析，實驗中共收集了30位受試者的資料，並結合其靜息態功能性磁振造影與面回訊頻譜影像(EPSI)，來比較預設模式網路區域與非預設模式網路區域(non-DMN)中的五種代謝物(NAA、Cre、Cho、mI、Glx)，研究結果以三個方法，共六個遮罩作計算分析，發現代謝物NAA和Cre與非預設模式網路區域相比，在覆蓋內側前額葉皮質(mPFC)、後扣帶回皮質(PCC)以及楔前葉(precuneus)的預設模式網路區域都顯示出較高的濃度基線。最後研究發現，代謝物NAA、Cre在預設模式網路區域與非預設模式網路區域發現有明顯的差異，但代謝物NAA會受不同方法的影響，較為不穩定。

Resting state functional magnetic resonance imaging (rsfMRI) can be used to measure the change in blood oxygen level-dependent (BOLD) contrast caused by neuronal activity. In previous studies, many resting state network composed of different brain regions have been found. When the person is at rest, and there is no specific task or stimulation, the neuron activity in the resting state network regions will be particularly active. Among all resting state network, the default mode network (DMN) has been proved to be stable and can be found when the human brain is resting. In addition, the neuron activity in the brain regions is closely related to metabolites. In this study, we analyze whether there is a difference in the metabolite concentration between DMN and the non-DMN. Data were collected from 30 subjects in the experiment, combining rsfMRI and echo planar spectroscopy imaging (EPSI) techniques to compare the five metabolites (NAA, Cre, Cho, mI, Glx) concentration between DMN and the non- DMN. The results are calculated by six masks. We found that NAA and Cre show higher baseline levels in DMN region covering part of medial prefrontal cortex, posterior cingulate cortex and precuneus than in non-DMN region. The concentrations of NAA and Cre are significant differences in DMN region and non-DMN region, but NAA is affected by different methods and is relatively unstable.

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