靜息態

呢啲 fMRI 圖片顯示咗個人腦某啲部位見到屋嗰時會活化，而另一啲部位就會喺見到人面嗰時活化。r 數值代表統計相關，數值愈高（正或者負）就表示啲腦區活動間愈有相關。

靜息態，又叫無任務 fMRI，係功能磁振造影（fMRI）上嘅概念，指緊個腦冇做咩特別工作嗰陣，用功能磁振造影睇到嘅活動規律。對於神經科學研究者嚟講，靜息態可以提供到好多有用嘅資訊，譬如係功能聯結呀噉。

基本概論

心理實驗嘅抽象圖解：企右手邊嘅研究者，要求受試者坐喺度對住個熒幕，可能係要受試者記住熒幕上出現過嘅詞語，考受試者嘅記憶。

功能磁振造影係一種非侵入式嘅神經造影技術，佢唔係直接量度神經元嘅電活動，而係量度隨住腦活動改變嘅血流。

傳統嘅功能磁振實驗會設計一啲任務^{[註 1]}，例如叫受試者郁手指、記一啲字詞或者望住某啲圖像，然後研究者就可以觀察受試者做任務嗰陣，邊啲腦區特別活躍，從而判斷邊啲腦區係負責做啲乜嘅。相反，靜息態就係冇指定任務^[1]，受試者只係靜靜哋坐喺度或者企喺度，通常研究者仲會要求佢雙眼望住某啲嘢或者合埋眼，防止視覺刺激對腦活動造成干擾，然後佢哋就觀察受試者腦區間自然出現嘅同步活動，睇吓佢哋係點樣互相連接嘅^[2]。

透過對靜息態嘅分析，神經科學研究者可以觀察到預設模式網絡等嘅大規模腦網絡。

功能聯結

如果話若干個（兩個或者以上）腦區之間有功能聯結^[3]，意思係話呢啲腦區彼此之間喺神經活動上有某啲特定嘅時間統計相關（皮亞遜積差相關係數）－例如兩個腦區 A 同 B，A 硬係會喺 B 出現強烈活動 0.5 秒之後跟住出現強烈活動，或者 A 同 B 硬係會一齊變得唔活躍。一般認為，如果若干個腦區之間有功能聯結，通常表示佢哋係一齊負責做某樣功能嘅^[4]。

功能聯結呢個概念，並唔局限於靜息態。任何情境，包括「有任務」嘅功能磁振實驗，都可能觀察到功能聯結^[5]。不過喺靜息態下，功能聯結零舍容易觀察：靜息態嘅實驗設計簡單，唔洗叫受試者做咩繁複嘅工作，適用於細路、老人家同病人等嘅受試者身上^[6]，因此功能聯結好多時都同靜息態研究緊密掛勾。

唔少神經科學同埋心理學嘅研究者都想分析功能聯結數據，而諸如 MATLAB 同 Python 等嘅工具仲有埋專化套件處理呢啲數據^[7]。

睇埋

註釋

↑ 譯自英文：task

引述

↑ Biswal BB (August 2012). "Resting state fMRI: a personal history". NeuroImage. 62 (2): 938–944. doi:10.1016/j.neuroimage.2012.01.090. PMID 22326802. S2CID 93823.
↑ Buckner RL, Krienen FM, Yeo BT (July 2013). "Opportunities and limitations of intrinsic functional connectivity MRI". Nature Neuroscience. 16 (7): 832–837. doi:10.1038/nn.3423. PMID 23799476. S2CID 17141252.
↑ 英文：functional connectivity
↑ Biswal, B. B., Kylen, J. V., & Hyde, J. S. (1997). Simultaneous assessment of flow and BOLD signals in resting‐state functional connectivity maps. NMR in Biomedicine, 10(4‐5), 165-170.
↑ Stevens, M.C., 2016. The contributions of resting state and task-based functional connectivity studies to our understanding of adolescent brain network maturation. Neuroscience & Biobehavioral Reviews, 70, pp.13-32，佢哋講咗呢句："... both resting state functional connectivity (rs-fcMRI) and task-based functional connectivity (t-fcMRI) have jointly contributed - albeit in different ways - to our understanding of..."
↑ Nielsen, J.A. and Hutchison, R.M., 2018. Resting-State Functional Connectivity MRI (fcMRI). In Encyclopedia of Clinical Neuropsychology (pp. 2996-3004). Springer, Cham，留意呢句："... offering a simple methodological approach to studying higher-order brain networks at a macroscale even in patients that may have difficulty performing certain tasks."
↑ Compute Functional Connectivity from Brain fMRI

[1] 譯自英文：task

[Biswal1-2] Biswal BB (August 2012). "Resting state fMRI: a personal history". NeuroImage. 62 (2): 938–944. doi:10.1016/j.neuroimage.2012.01.090. PMID 22326802. S2CID 93823.

[Buckner-3] Buckner RL, Krienen FM, Yeo BT (July 2013). "Opportunities and limitations of intrinsic functional connectivity MRI". Nature Neuroscience. 16 (7): 832–837. doi:10.1038/nn.3423. PMID 23799476. S2CID 17141252.

[4] 英文：functional connectivity

[5] Biswal, B. B., Kylen, J. V., & Hyde, J. S. (1997). Simultaneous assessment of flow and BOLD signals in resting‐state functional connectivity maps. NMR in Biomedicine, 10(4‐5), 165-170.

[6] Stevens, M.C., 2016. The contributions of resting state and task-based functional connectivity studies to our understanding of adolescent brain network maturation. Neuroscience & Biobehavioral Reviews, 70, pp.13-32，佢哋講咗呢句："... both resting state functional connectivity (rs-fcMRI) and task-based functional connectivity (t-fcMRI) have jointly contributed - albeit in different ways - to our understanding of..."

[7] Nielsen, J.A. and Hutchison, R.M., 2018. Resting-State Functional Connectivity MRI (fcMRI). In Encyclopedia of Clinical Neuropsychology (pp. 2996-3004). Springer, Cham，留意呢句："... offering a simple methodological approach to studying higher-order brain networks at a macroscale even in patients that may have difficulty performing certain tasks."

[8] Compute Functional Connectivity from Brain fMRI

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