心跳變異生理反饋：如何及為何能發揮作用？(下) | Heart rate variability biofeedback: how and why does it work?

心跳變異生理反饋：如何及為何能發揮作用？(下) | Heart rate variability biofeedback: how and why does it work?

心跳變異生理反饋：如何及為何能發揮作用？

Heart rate variability biofeedback: how and why does it work?

 

其他潛在治療作用機制

由於HRV生理反饋顯然對涉及各種生理系統的病症（疼痛、焦慮、抑鬱、慢性阻塞性肺病、血壓控制、運動表現等）有幫助，因此除了感壓感反射之外，很可能還涉及多種機制以產生各種影響。副交感神經傳入的刺激和影響，大部分尚未受到實證關注，但它們都相當值得進行研究，這些可能機制包括：

 

副交感神經傳出影響

副交感神經活動通常是“放鬆反應”的一個組成部分。HRV反饋刺激副交感神經反射可能會產生具放鬆特點的身體自主活動，進而直接對抗壓力效應。可能發生此一情況的一種方式是被稱為“強化對抗（Accentuated Antagonism）”的機制。副交感神經的音調在休息時主導了交感神經。在正常生理條件下，突然而來的副交感神經刺激會抑制強直性交感神經的啟動及其在休息和運動時的作用，這種反應就是前面所提到的”強化對抗” （Olshansky et al., 2008, p. 863）。根據推測，副交感傳出系統的這一方面可以透過HRVB訓練得到加強，這可能可以抑制交感神經向肌筋膜激痛點的輸出（Hubbard and Berkoff, 1993; Gevirtz et al., 1996; Hubbard, 1998）。倫敦Aziz研究小組（Hobson et al., 2008）的研究也證實，當酸進入胃時，緩慢呼吸幾乎可以立即讓食道疼痛閾值急劇下降。

 

提升氣體交換率

由於諧振頻率呼吸期間呼吸與心率之間存在0°相位關係，改善氣體交換可能有助於患有呼吸系統疾病的人，甚至可能降低患有壓力引發過度換氣（Stress-Induced Hyperventilatory）反應者的呼吸動力。

 

冥想效果

心率變異性生理反饋涉及密切關注呼吸的細微差別。這與正念冥想練習中的做法非常相似。這裡的途徑主要是精神上的：也就是個體不能在專注放鬆呼吸的同時去擔心一天當中的各種問題。

 

呼吸道的機械彈性

對哮喘的影響可能是深呼吸伸展了肺部上皮組織作用間接發生的。已知在肺可靈激發試劑（methacholine）檢驗過程中，僅單次深吸即可降低哮喘患者氣道對試劑反應性（Pellegrino et al., 1996; Marchal et al., 2002）。

 

抗炎作用

副交感神經系統與炎症系統有著密切相互作用，因此副交感神經通路增加（一般經由副交感神經電刺激產生）與血清中的各種炎症細胞激素含量降低相關（Borovikova et al., 2000; Tracey, 2002）。一項研究已發現高血壓患者接受HRV生理反饋治療後的C反應蛋白有所減少（Nolan et al., 2012）。另一項研究中則是在實驗內將健康受試者暴露於炎症細胞激素脂多醣當中（Lehrer et al., 2010）。一般來說，交感神經和副交感神經的活性都會被脂多醣所阻斷。雖然並未發現HRV生理反饋誘導下讓炎症細胞激素減少，但發現炎症自主神經效應受到極大調節，表示有接受HRV 生理反饋的個體存有更大的彈性。

 

結論

本文試圖總結有效性的可能機制，建立假設討論感壓反射增加即為自主神經穩態改善或複雜性增加的可行標誌。對於此一結論進行一系列證據回顧，這些證據經由本文實驗室及其他研究者證實，因此可推測與此類機制相結合下，副交感神經傳入系統的刺激也可能發揮作用，特別是在消極情感障礙當中。

 

利益衝突聲明 : 作者聲明本研究是在不存在任何可能被視為潛在利益衝突的商業或財務關係情況下進行。

 

 

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