淨化呼吸瑜珈 (Sudarshan Kriya Yoga, SKY) 是一種呼吸介入方法，規律練習可以改善心率變異 (Heart rate variability, HRV)、身心靈健康，並且可有效改善情緒障礙和憂鬱症。大腦預設模式網路 (Default mode network, DMN) 包括內側前額葉皮質、眶額葉皮層、前扣帶迴、後扣帶迴、楔前葉、下頂葉、杏仁核和海馬迴。最初發現DMN腦區活性在受試者執行認知作業時降低，在休息時其活性增加。淨化呼吸瑜珈能否改變DMN內的腦區活性和功能連結仍是未知。因此，我們假設淨化呼吸瑜珈對改善心率變異與DMN之間有關聯。本研究中，我們使用靜息態功能性磁振造影 (Resting-state functional magnetic resonance imaging, rs-fMRI) 來探索在淨化呼吸瑜珈練習前後大腦DMN內的區域活動和功能連結，在這項研究中，受試者需要學習淨化呼吸瑜珈並保持每周至少3次以上的練習，另外我們使用看影片的方式當作對照。在rs-fMRI期間使用光學式心跳測量儀器檢測手指脈搏，並利用心跳間隔分析其心率變異。在心率變異的結果中發現，淨化呼吸瑜珈和看影片都顯著降低心跳速率並增加心率變異參數 SDNN、RMSSD及pNN20之值。然而，淨化呼吸瑜珈和看影片對DMN腦區活性和功能連結有不同的差異變化。區域同質化分析發現，淨化呼吸瑜珈練習後與練習前相比，左側眶額葉皮層的活性降低；另外看影片後與看影片前相比發現，後扣帶迴和楔前葉區域活性增加。而功能連結的結果顯示，在淨化呼吸瑜珈練習後，DMN腦區間有六對功能連結上升，兩對功能連結下降；但看影片後，卻沒有發現任何DMN間的功能連結發生顯著變化。DMN腦區活性或功能連結與各項心率變異參數的相關分析發現，在淨化呼吸瑜珈練習後，左腦前眶額葉皮質區域活性下降與SDNN上升呈負相關；右腦前眶額葉皮質與左腦或右腦下頂葉功能連結下降與RMSSD或pNN20上升呈負相關；右腦杏仁核與左腦杏仁核功能連結上升與pNN20上升呈正相關。看影片後，左腦楔前葉活性上升分別與SDNN、RMSSD以及pNN20上升呈正相關；右腦楔前葉活性上升與SDNN上升呈正相關；右腦下頂葉活性上升與SDNN上升呈正相關。最後，本研究結果表明，淨化呼吸瑜珈練習不僅改善了迷走神經調節的心率變異，而且還改變了與自律神經調節有關的DMN區域的區域活性及功能連結。

Regular practicing of Sudarshan Kriya Yoga (SKY) improves heart rate variability (HRV). Default mode network (DMN) includes the medial prefrontal cortex (mPFC), orbitofrontal cortex (OFC), posterior cingulate cortex (PCC), precuneus (PCUN), anterior cortex (ACC), inferior parietal lobe (IPL), amygdala (AMG) and hippocampus (HPC). Initially, DMN was found to be involved in various domains of cognitive and social processing. Whether SKY can change the regional activity and functional connectivity (FC) within DMN is still unknown. In this study, we have recruited 33 participants who had learned SKY and regularly practice 3 times a week. Each participant experiences two days of resting-state magnetic resonance imaging (rs-fMRI) and photoplethysmographic (PPG). On one day, practicing SKY for 35 minutes, and on the other day was 35 minutes of video watching as control. Results showed that SKY and video watching increased HRV. Analyses of regional homogeneity (ReHo) found that the activity of left OFC decreased after SKY practicing. In contrast, the activity of PCC and PCUN increased after video watching. Analysis of FC revealed that connectivity between bilateral mPFC and left AMG increased after SKY practicing. However, we did not find any FC changed within DMN after video watching. After SKY practicing, △HRV was correlated with △ReHo of left OFC; △HRV was correlated with △FC between right OFC and bilateral IPL; left and right AMG. After video watching, △HRV was correlated with △ReHo of right IPL and bilateral PCUN. Our results suggest that SKY practicing improves the vagal-mediated HRV, regional activity and FC of brain regions involved in autonomic regulation within DMN.

許庭維 (2019) 淨化呼吸瑜珈在家練習增加迷走神經調節之心率變異與靜息態杏仁核功能性連結，成大生理所碩士論文。
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