Assessment of dynamic characteristics of cardiac RR intervals during meditation using Poincaré plot and sequence trend analysis
Charunayan Kamath
Journal of Cardiology & Current Research December 6, 2018 DOI: 10.15406/jccr.2018.11.00415 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Review Peer reviewed |
|---|---|
| Topics | Meditation |
| Key findings | The article proposes that meditation is a complex physiological process influencing psychological, behavioral, neural, and autonomic functions, and is regarded as an altered state of consciousness distinct from wakefulness, relaxation, and sleep. It argues that most meditation techniques affect the autonomic nervous system, with respiration central to the mind-body link, and that heart rate variability analysis is a valuable noninvasive tool for studying autonomic function, though nonlinear and nonstationary heart rate data complicate interpretation. |
Abstract
Found in cultures, spiritual traditions, and healing practices throughout the world, meditation is a mind-body practice with different approaches and variations, which began probably more than five thousand years ago. Since then it has developed and practiced to understand consciousness and improve health conditions. All these meditation techniques can be broadly classified under two categories: concentration meditation and insight meditation.1 In the former, attention is focused on the breath to still the mind. As the meditator concentrates on the breath, the mind gets absorbed in the inhalation and exhalation which may lead a state of silence mind, usually called The Samadhi state. The insight meditation involves opening the attention to become aware of the continuously passing of sensation and the feeling without getting involved into the thoughts about them.2 Meditation is a complex physiological process which affects psychological, behavioral, neural and autonomic functions and is regarded as an altered state of consciousness, different from wakefulness, relaxation at rest and sleep.3−5 Many have shown that the meditation practice leads to functional changes in physiological states of humans.6−8 It is found that most of the meditation techniques affect the ANS which in turn regulates organs and muscles thereby controlling vital functions such as heart beat, respiration, and digestion. In fact respiration is one of the autonomic functions that can be controlled and affect the functioning of the ANS.9 As an implication many of the meditation practices consider respiration, mind and body as linked, with respiration having a central role. HRV analysis is fast emerging as a noninvasive research and clinical tool for assessing cardiac and ANS function.10,11 The analysis of HRV, in general, is a difficult task due to the nonlinearity and nonstationarity of the RR interval time series. Traditional HRV analysis methods are based on linear methods in the time, frequency or time-frequency domains. Such methods have been widely used to study sympathetic and parasympathetic activities. These methods assume stationarity of the time-series within the sample, an assumption that is often violated in the heart rate series. Heart rate often changes in an asymmetric fashion and this leads to complexity in the interpretations of the results. Nonlinear methods are being explored since it has been found that nonlinear phenomena are involved in the genesis of HRV.12−14 Many studies have shown that HRV is reduced in various diseases and old age.15,16 Even in predicting mortality of survivors of myocardial infarction, reduced HRV is used as a marker.17,18 In the context of meditation, the study of HRV offers a unique approach to view into the complex mindbody connection that exists behind the regulation of life processes, such as blood circulation, and breathing. Analysis of HRV signals is important when studying the ANS because it helps in evaluating the dynamic interaction and the equilibrium between the sympathetic and parasympathetic influences on the heart rate. The sympathetic branch of nervous system increases the heart rate, resulting in shorter beat intervals. On the other hand, the parasympathetic branch decreases the heart rate, resulting in longer beat intervals. Thus the HRV can be evaluated based on beat intervals or RR intervals. Meditation, perhaps, is well suited to investigate intrinsic properties of the ANS since it involves a state of complete physical immobility and almost absence
Comparable studies
Other narrative reviews on meditation, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Mindfulness training as a clinical intervention: A conceptual and empirical review. Clinical populations | 2003 | Review | |
| Mindfulness: Theoretical Foundations and Evidence for its Salutary Effects | 2007 | Review | |
| Mindfulness Interventions | 2016 | Review | |
| Mind the Hype: A Critical Evaluation and Prescriptive Agenda for Research on Mindfulness and Meditation | 2017 | Review | |
| Mindfulness and acceptance: expanding the cognitive-behavioral tradition | 2005 | Review |