探討禪定組和控制組之心肺交互作用與心肺相位同步分析

Abstract

本研究的目的是利用分析心率變異(Heart rate variability, HRV)、呼吸性竇性心律不整(Respiratory sinus arrhythmia, RSA)的表現和相位同步分析來探討禪定者與正常控制組的心肺交互作用。心率變異時域分析提供了評估自主神經系統在不同心理壓力階段下的訊息，頻域分析方法則是藉由低頻高頻功率比(LF/HF)來估測。在低呼吸率時，傳統的HRV分析(tHRV)方法會造成『低頻高頻功率比』的估測值過高，故本研究使用適應性頻域範圍(Adaptive frequency range, AFR)方法改進上述的缺點。量化呼吸性竇性心律不整顯示了每位受測者心律和呼吸之間的相關性。此外，我們運用本質模態函數(Intrinsic mode functions, IMF)、連續小波轉換(Continuous wavelet transform, CWT) 兩種方法，接著藉由希爾伯特-黃轉換(Hilbert-Huang Transform, HHT)獲得更為準確的瞬時相位，進而量化心肺同步現象。 本論文中所分析的對象包括兩個群組，禪定組為7位具有禪坐經驗者、控制組則為25位健康受測者。根據心率變異分析結果，多數的控制組受測者於呼吸引導階段下與禪定組受測者禪定階段下，自主神經系統有著較佳的活性且由副交感神經主導。在量化呼吸性竇性心律不整的分析中，控制組受測者於呼吸引導階段下更能維持較明顯的呼吸性竇性心律不整現象。最後在相位同步率分析中，我們發現無論是在禪定狀態(實驗組)或是呼吸引導狀態下(控制組)，受測者都有著較高的心肺同步率。因此，我們可以得出結論，禪定能很好地保持心肺相互作用。

This research is aimed to investigate the cardiorespiratory interaction of Zen-meditation practitioners (Zen-meditation group) and ordinary practitioners (control group) by heart rate variability (HRV), respiratory sinus arrhythmia (RSA) behavior and cardiorespiratory phase synchronization analysis. In the time-domain HRV analysis, it provides the information for evaluating the activity of autonomic nervous system (ANS) at different mental-stress levels. In the frequency-domain, HRV behavior is quantified by the ratio of low-frequency power to high-frequency power (denoted by LF/HF) of HRV spectrum. In traditional HRV analysis (tHRV), the ratio LF/HF is very likely to be overestimated, in this study, adaptive frequency range (AFR) method are developed to deal with the issue. Quantification of respiratory sinus arrhythmia reflects the correlation between cardiac rhythm and respiratory pattern in each subject. In addition, the cardiorespiratory synchronization phenomenon is quantified by the following schemes for comparison, intrinsic mode functions (IMF), continuous wavelet transform (CWT), and Hilbert-Huang Transform (HHT). This study involved 32 subjects, 7 Zen-meditation practitioners and 25 control subjects without any meditation experience. According to our HRV results, most subjects exhibit vigorous ANS activity with parasympathetic dominance at the Zen meditation (experimental group) or in the breathing-control session (control group). In the RSA analysis, breathing-control session induces more apparent respiratory sinus arrhythmia phenomenon in control group. Moreover, higher cardiorespiratory synchronization degree appears either at the Zen meditation or in the breathing-control session. Therefore, we may conclude that Zen meditation can well maintain the efficiency of cardiorespiratory interactions.