Heart rate dynamics in different levels of Zen meditation

doi:10.1016/j.ijcard.2009.06.058

International Journal of Cardiology

Volume 145, Issue 1, 5 November 2010, Pages 142-146

https://doi.org/10.1016/j.ijcard.2009.06.058 Get rights and content

Abstract

The dynamic interactions among physiological rhythms imbedded in the heart rate signal can give valuable insights into autonomic modulation in conditions of reduced outward attention. Therefore, in this study we analyzed the heart rate variability (HRV) in different levels of practice in Zen meditation (Zazen). Nineteen subjects with variable experience took part in this study. In four special cases we collected both HRV and respiration data. The time series were analyzed in frequency domain and also using the Continuous Wavelet Transform, which detects changes in the time domain and in the frequency domain simultaneously. The shifts in the respiratory modulation of heart rate, or respiratory sinus arrhythmia (RSA), reflect the different levels of practice among practitioners with variable experience in Zazen; in turn the modulation of the RSA may reflect changes in the breathing pattern as in the parasympathetic outflow related to the quality and focus of attention in each stage.

Introduction

In this study we investigate the heart rate variability (HRV) during Zen meditation (Zazen), in order to study the system behavior in the absence of voluntary intention. The terms “focused attention” (FA) and “mindfullness” (MM) used throughout this paper are defined as follows: FA is the attention focused on the natural breathing process and is specially used by novice Zen practitioners. MM defines a no-pointed attention state where the mind passively observes the spontaneous experience, primarily as a means to recognize the nature of emotional and cognitive patterns [1]. On this basis we consider the definition for “meditation” in [2] limited to just one aspect of a broadest term.

Section snippets

Subjects

Nineteen Soto-Zen meditation practitioners who have between 2 months and 20 years of experience (7 females and 12 males, mean age 43.78 ± 7.52 years), are represented in this study. None reported any cardiovascular disease and did not take any medication. They did not eat or take any stimulating drink in the last 2 and 24 h, respectively, before data recording. Informed written consent (in accordance with the Helsinki Declaration) was obtained from each subject.

Data collection

RR interval data were collected by

Results

The PCA separated three different groups (Fig. 1). Novice practitioners with less than 1 year of practice present a resonant peak in the VLF or LF range and were not included in the PCA (Fig. 2).

Fig. 3 shows the FFT of HRV and breathing data for subjects S6 and S8 (G1) during MM and FA. Fig. 4 shows the same data for subjects S16 and S19 (G3). Note in Fig. 3, Fig. 4 (subplots a and b) as it seems that there is a tendency towards frequencies coupling as regards the number of years the subjects

Discussion

The presence of a resonant peak in the spectrum is characteristic among novices and experienced Zen meditators. It is in accordance with [6]. Nevertheless, the novices focus on and also silently count their respirations, which probably work as a rhythmic stimulus. Other authors also found that different rhythmical stimulations elicit high-amplitude oscillations in cardiovascular functions at resonant frequencies [7], [8], [9].

With expertise the need for voluntary attention efforts to attain

Acknowledgments

The authors acknowledge Zen Master Dokushô Villalba, founder and director of the Luz Serena Temple, for his guidance and facilitation in this work; and also the community of Luz Serena and Dojo Zanmai San for their sincere collaboration. The authors of this manuscript have certified that they comply with the Principles of Ethical Publishing in the International Journal of Cardiology [13].

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Letter to the EditorHeart rate dynamics in different levels of Zen meditation

Abstract

Introduction

Section snippets

Subjects

Data collection

Results

Discussion

Acknowledgments

Trends Cogn Sci

Int J Cardiol

Int J Cardiol

Neurosci Biobehav Rev

Int J Cardiol

Power spectral analysis of heart rate variability: a noninvasive signature of cardiac autonomic function

Crit Rev Biomed Eng

Letter to the Editor
Heart rate dynamics in different levels of Zen meditation