COHERENCE   & The New Science of Breath




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Respire I by Coherence

The Six Bridges !

Swarovski Crystal Reminder Bracelet

Swarovski Crystal Reminder Bracelet by Coherence

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Taiji Diagram

Coherence Clock

Coherence Clock by Coherence

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Horizontal        Pratyahara

Horizontal Pratyahara by Coherence

Clock & Tibetan Bell

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Tibetan Bell and Marimba by Coherence

Tibetan Bell &        Chime

Vocal Instructive        Sequence (Aqua)

2 Bells

Mountain Brook &         Chime

Single Chime

4 Bells


                                                                                                                            June 16 , 2006

The Science:


COHERENCE(TM) represents a formative “New Science of Breath(TM)". This new science is based on a breakthrough in the understanding of autonomic nervous system balance and its relationship to subtle heart and breathing rhythms.

"Coherence", refers to amplitude, frequency, and phase regularity of the intrinsic autonomic nervous system rhythm as reflected in the variability of the heart rhythm (HRV). Amplitude and frequency characteristics of this rhythm have been shown to be indicative of both physiological and psychological status. Amplitude of this rhythm is primarily a function of breathing frequency/depth whereas coherence of this rhythm is primarily a function of breathing "synchrony", for without synchronous breathing, although relative, coherence is not possible. Maximal amplitude and coherence result when heart rate variability (HRV) and breathing rhythms are synchronized. This synchrony both results-in, and is a result-of, balance between sympathetic and parasympathetic functions as well as a synergistic harmony between autonomic and somatic branches of the central nervous system. (The autonomic nervous system consists principally of two antagonistic divisions, the sympathetic division - responsible for "activating" functions, and the parasympathetic division - responsible for "deactivating" functions. Working together, sympathetic and parasympathetic divisions "autonomously" strive to establish and maintain homeostasis.)

         FIGURE 1: Breathing Rate vs. Autonomic Nervous System Emphasis                

 ("Mild", "moderate", and "severe" divisions are arbitrary.)

For adults in the state of rest or semi-activity, optimal synchrony between HRV and breathing rhythms occurs at a specific frequency, this being 1 cycle in ~12 seconds, or 5 cycles in ~1 minute. When operating at this pace, cardiopulmonary efficiency and effectiveness are maximized and in keeping with the fundamental underlying autonomic nervous system rhythm. cardiopulmonary operation at this rhythm is characterized by relatively low average heartbeat rate, maximized heart rate variability amplitude, and maximized heart rate variability coherence.

There is growing acceptance within the broad medical community that HRV amplitude is a key indicator of health status, adequate amplitude being indicative of sound health and inadequate amplitude being indicative of health risk. Furthermore, HRV "coherence" is emerging as a key indicator of autonomic nervous system balance, this balance or lack thereof manifesting in overall emotional and physiological status - coherence being strongly indicative of psychological/ physiological harmony and incoherence being equally indicative of its opposite.(7)

Referring to FIGURE 1, when in the state of rest or semi-activity, the autonomic nervous system takes its cue from the breathing frequency. Breathing at a relatively rapid pace, even while seated and otherwise relaxed, results in an autonomic shift toward sympathetic emphasis, sympathetic emphasis often being characterized as the “fight or flight” response. The degree of emphasis varies directly with the rate of breathing. Sympathetic emphasis is characterized by relatively faster average heartbeat rate, reduced heart rate variability, increased heart duty cycle, and reduced heart rate variability coherence, as well as other physiological and psychological changes.

There is an emerging understanding within the medical community that sympathetic dominance underlies many modern day maladies including anxiety and hypertension. What is not understood is the root cause of sympathetic dominance. COHERENCE asserts the theory that the root cause of sympathetic dominance is in fact suboptimal breathing. Breathing at the The Fundamental Quiescent Rhythm, brings about autonomic nervous system balance, correcting the state of sympathetic over activity and parasympathetic under activity and its consequences including internal tension, anxiety, and potentially the myriad of other psycho-physiological challenges to health and well being resulting from this imbalance. By adopting the breathing rate of 1 cycle in ~12 seconds or 5 cycles in ~1 minute as one’s “normal” resting breathing rate, autonomic balance can be realized and sympathetic dominance and its myriad affects averted. No specific claims are made regarding health benefits.

Why 1 cycle in ~12 seconds? For adults in the state of rest or semi-activity, if the breathing cycle is synchronized with the heart rate variability cycle, the resulting center frequency and primary component of the heart rate variability frequency spectrum is .085 cycles per second or 1 cycle in ~12 seconds. Because this is the "natural frequency" at which the cardiopulmonary system inclusive of nervous system aspects resonates, at this frequency, heart rate variability and coherence are maximal. You can experience this rhythm in an instructive format by clicking here. (Requires RealPlayer)

Technical Discussion:

Because the intrinsic autonomic nervous system rhythm manifests in the rate at which the heart beat rate changes, heart rate variability is a "window" into autonomic status. For this reason, to understand “coherence”, it is first necessary to understand heart rate variability (HRV). Most people are familiar with “heartbeat rate” expressed in beats per minute (BPM). Heartbeat rate refers to the absolute number of heartbeats occurring during a 60 second period.

Heart rate variability (HRV) refers to the natural variation in heartbeat rate that occurs over a period of time. For our purposes, (average) heart rate variability is expressed by the following formula:

HRV(av)= [((peak high rate 1 - peak low rate 1)+(peak high rate n -peak low rate n))/n]

To make this clear, FIGURE 2 below presents a real measurement of 13 complete heart rate variability cycles, numbered 1-13 from left to right. The X axis equals time and the Y axis equals heartbeat rate in beats per minute (BPM). For ease of analysis, a heart rate variability sample that also exhibits a relatively high degree of frequency/phase regularity or “coherence” is chosen. The gray line represents the actual heartbeat rate as it varies in time from left to right. The top peaks of the gray line represent the highest heartbeat rate in beats per minute (BPM) on a per cycle basis. Similarly, the bottom "valleys" represent the lowest heartbeat rate in beats per minute (BPM). The top and bottom red lines labeled "High" and "Low" have been added for clarity throughout the document.

FIGURE 2: Modest HRV, Relatively High Coherence (actual measurement) 

The difference between the highest and lowest heartbeat rate on a per cycle basis is depicted along the center of the graph, 12, 7, 11, 16, etc. Averaging these across all 13 samples yields an HRV(av) = 11 BPM.

The heartbeat naturally varies with the breathing cycle, this phenomena being referred to as “respiratory sinus arrhythmia” (RSA). The relationship between the heartbeat rate and the breathing cycle is such that heartbeat rate tends to increase coincident with inhalation and decrease coincident with exhalation. As such, the amplitude and frequency of the heart rate variability pattern relates strongly to the depth and frequency of respiration. Consequently, FIGURE 2 represents a modest heart rate variability with relatively shallow synchronous breathing. As noted in the figure, this HRV signature was recorded while consciously breathing at 7.5 cycles per minute.

Respiratory sinus arrhythmia and heart rate variability in general are governed by complex interactions between sympathetic and parasympathetic functions as well as neural feedback resulting from the mechanical action of the cardiopulmonary system. Respiratory sinus arrhythmia is the physiological consequence of the dynamic interaction of cardiac and pulmonary centers located in the medulla oblongata.(14)

Heart rate variability itself is the subject of much scientific interest. While science recognized the existence of HRV and RSA as early as the 1700s, until the advent of powerful computing, the tools did not exist to thoroughly characterize its action and role in vertebrate physiology. At this juncture, several decades of research aided by contemporary computing, in particular, real time fast Fourier transformation, have passed. Via numerous independent research studies, heart rate variability is emerging as a reliable indicator of stress level and age, varying inversely with both factors.(1)

FIGURE 2 demonstrates a moderate heart rate variability (HRV(av) =11 BPM). For contrast, FIGUREs 3 and 4 present HRV samples with low variability/coherence and high variability/ coherence, respectively.


FIGURE 3: Low HRV, Low Coherence (actual measurement)


FIGURE 4: High HRV, High Coherence (actual measurement)

Figures 2 and 4 are records of the same person breathing at 7.5 breaths per minute and 5 breaths per minute respectively. For completeness, FIGUREs 5 and 6 present HRV signatures while breathing at 15 and 30 breaths per minute. X and Y scales for FIGURES 1-7 are the same.

FIGURE 5: Low HRV, Modest Coherence (actual measurement)

FIGURE 6: Low HRV, Modest Coherence (actual measurement)

Another HRV example is worth noting. This is the relatively high but chaotic pattern presented in FIGURE 7. This signature is characteristic of relatively deeper asynchronous breathing. Even now , HRV(av) is difficult to calculate for chaotic signatures without sophisticated processing techniques. For this reason, most HRV investigators have their subjects employ some form of synchronous breathing so as to take advantage of respiratory sinus arrhythmia effects.

FIGURE 7: Moderate Variability With Chaotic Periodicity (actual measurement)

At this point, it is necessary to look more deeply into the relationship between heartbeat rate and breathing. Let’s examine HRV differences as they vary with breathing rhythm. For purposes of comparison, FIGURE 8 presents a sinusoidal model approximating the HRVs of FIGURES 2, 4, 5, and 6, these being represented by blue, green, orange, and red, respectively. Again, FIGUREs 2 and 4-6 are HRV signatures of the same person deliberately breathing at 4 different frequencies and otherwise seated and at rest.

FIGURE 8: Model Comparing 5, 7.5, 15, 30 Breathing Cycles Per Minute

Several things are immediately apparent:

1) HRV amplitude shrinks dramatically as breathing frequency increases.

2) The fascinating thing about this is that increasing the breathing frequency by as little as 2.5 breaths per minute results in a dramatic shift upward in HRV valleys. Contrasting the green and blue lines, 5 breaths per minute yields 60 beats per minute whereas 7.5 breaths per minute yields 77.5 beats per minute, a difference of 17.5 beats per minute!

3) Contrasting the red and green lines representing the highest and lowest breathing rates, in relative terms, rapid breathing results in the heart working on a continuous basis much faster than slower breathing. To be clear, at 30 breaths/minute the heartbeat rate varies between approximately 91 and 93 BPM, never slowing down below ~91 BPM. At 5 breaths per minute the heartbeat rate varies between ~60 and 94 BPM. 50% of the time it is below 77 BPM and ~77% of the time it is below 91 BPM.

4) The average heartbeat rate, by definition being the HRV mean, shifts upward as breathing frequency increases.

FIGURE 9 presents the same information in line graph format. Here it can be seen that above ~7.5 breaths per minute, the average heartbeat rate varies in a highly linear fashion at approximately 3 beats per minute/7.5 breaths up to 30 breaths per minute.


FIGURE 9: Line Graph Depicting Heartbeat Rate vs. Breathing Rate

The critical issue is not that more rapid breathing results in increased sympathetic emphasis. The critical issue is that rapid breathing strongly negates parasympathetic emphasis. If we once again examine the HRV corresponding to 5 breathing cycles per minute, we see that its sympathetic aspect (peak) is just as pronounced as that of 30 breaths per minute, both approximating 93-95 beats per minute. On the other hand, the valley relating to 30 breaths per minute as compared to 5 breaths per minute diminishes by over 30 beats!

If we accept that the valley represents the moment of maximal cardiopulmonary rest and relaxation and minimal arterial pressure, and that it represents the moment of minimal action on the part of the autonomic nervous system at large, then it is this rest period that is sacrificed. Given that this “signal” is communicated by the autonomic nervous system throughout the body, this rest period is sacrificed relative to the entire organism.

If we do a gross analysis comparing the increase in sympathetic emphasis vs. the decrease of parasympathetic emphasis at 5 vs. 15 breaths per minute, the breathing rate of the average adult, it would look something like this.

5 Breaths Per Minute
15 Breaths Per Minute
Delta Heartbeat Rate
% Change
(Beats Per Minute)
(Beats Per Minute)

In other words, 15 breaths per minute yields 6% less sympathetic influence (a positive effect in the context of throttling sympathetic action), and 40% less parasympathetic influence (a negative effect in the context of parasympathetic influence and autonomic nervous system balance). Note that while this heart rate variability difference is very large, there is only a 12% difference in average heartbeat rate, 5 breathing cycles per minute being 12% lower than 15 breaths per minute. For this reason, average heart beat rate belies the true condition of cardiopulmonary status, heart rate variability being a far more comprehensive measure.

Relative to FIGURE 8, note that as breathing frequency increases, heart rate variability amplitude rapidly decreases, resulting in a slightly higher average heartbeat rate but a much higher coronary "duty cycle". Secondly, as the blood carrying capacity of the cardiovascular system (i.e., vessel dimensions) is modulated by sympathetic activity, increased breathing frequency resulting in increased sympathetic emphasis results in decreased arterial capacity and higher arterial pressure. Consequently, it stands to reason that breathing frequency and depth play a key role in moderating blood pressure. Given that the average adult (at sea level) breathes between 10 and 20 times per minute(3), does suboptimal breathing not play a significant part in the present hypertension pandemic? Of what consequence is this to health and longevity?

It is very important to understand that these measurements are taken while seated and completely at rest with the exception of consciously breathing at different rates. From this observation, it appears evident that the cardiopulmonary system inclusive of central nervous system aspects, takes its cue from the breathing rate, i.e. the shorter the breathing cycle, the faster the average heartbeat rate and lower the heart rate variability amplitude. In this regard, the behavior appears highly similar to the functioning of the cardiopulmonary system during exercise, but in the exercise case the system accelerates in order meet the increasing energy requirement.

Autonomic Balance & Coherence:

Our specific interest is in understanding the state of optimal autonomic balance, this state being characterized as the harmonious equilibrium between sympathetic and parasympathetic functions as well as a synergistic harmony between autonomic and somatic aspects of the central nervous system.

The cardiopulmonary system inclusive of central nervous system aspects behaves much like an oscillator. R.I. Kitney of the Imperial College of London asserted this general concept in his paper to the First International Symposium on Cardiovascular Respiratory and Somatic Integration in Psychophysiology held in 1983.(5)



FIGURE 10: Oscillator Model of Cardiopulmonary System

The present author proposes that this hypothetical cardiopulmonary oscillating system is approximated by that of FIGURE 10. It has a natural center frequency of 1 cycle in ~12 seconds that is determined primarily by the characteristics of hypothetical oscillating and feedback-loop elements. Henceforth, this specific frequency is referred to as “The Fundamental Quiescent Rhythm, the primary underlying rhythm at which the cardiopulmonary system inclusive of autonomic nervous system aspects naturally resonates.

In this model, the oscillating element has a “sync” input by which the frequency of oscillation is firmly coupled to the frequency of respiration. Consequently, the system tends to operate at the center frequency of 5 cycles per minute but is modified by the frequency of respiration. As such, the frequency of respiration can “push” the output frequency above 5 cycles per minute or “pull” the output frequency below 5 cycles per minute.(5) This effect can be seen in FIGURES 2, 4, 5, 6, and 12, each presenting HRV measured at a different breathing frequency. While, generally speaking, the oscillator will synchronize with the breathing cycle as long as the breathing cycle is synchronous, the amplitude of the output is maximal when the frequency and phase of respiration are identical to that of the oscillator. FIGURE 4 is an actual measurement of HRV while breathing at 5 cycles per minute. The HRV of FIGURE 4 is 33 BPM while the average heartbeat rate is 77 BPM. Consequently, the HRV of FIGURE 4 is ~43% of the average heartbeat rate.

Heart rate variability is a "window" into autonomic nervous system balance and presently one of the only practical ways to observe this intrinsic autonomic nervous system rhythm. FIGURE 11 presents a spectral analysis of the heart rate variability signal while breathing at the Fundamental Quiescent Rhythm, plotting HRV frequency vs. power as averaged over a period of interest. This spectral signature is highly symmetrical, demonstrating that theassociated HRV signal possesses a high degree of spectral purity, frequencies being largely contained to a relatively narrow band around the center frequency of .085 cycles per second. This narrow band and high symmetry demonstrates that the “Q” of the hypothetical cardiopulmonary oscillator is quite high, lending further credence to its existence in fact.

This particular spectral signature is of special significance because it is representative of optimal autonomic nervous system balance, spectral components to the left of the peak being reflective of sympathetic activity and spectral components to the right being reflective of parasympathetic activity. In this case, with the exception of equal frequency components to the immediate left and right of the “monument” centerline, there are neither. (The secondary peak representing the second harmonic is a vestige resulting from the digital signal processing based measurement method.)

FIGURE 11: HRV Power Spectrum While Breathing At The Fundamental Quiescent Rhythm  (actual measurement)

Again, in order for HRV amplitude and coherence to be maximized, the breathing cycle must be highly aligned with the Fundamental Quiescent Rhythm. If the frequency of the breathing cycle occurs even slightly to either side of the 5 cycles per minute center frequency, HRV amplitude and coherence will not be maximized. An example of this is depicted in FIGURE 12 where the breathing rate is 4 cycles per minute.

FIGURE 12: HRV Distortion At Breathing Fequency of 4 Cycles Per Minute (actual measurement)

As compared to FIGURE 4, it can be seen that the HRV waveform is beginning to degrade. This distortion increases as the frequency of breathing slows below 5 cycles per minute.

The Emerging Understanding of HRV & Coherence:

HRV status is coming to be accepted as an accurate indicator of health/health risk, ample amplitude and phase/frequency regularity (coherence) being indicative of relatively low "allostatic load" (internalized stress level) and autonomic tone/balance, and low amplitude HRV and phase/frequency irregularity being indicative of its opposite. HRV amplitude is also emerging as an accurate marker of cardiovascular age.(1)

Vertebrate biology is arranged to operate in a harmoniously balanced manner, the ebb and flow of which is principally governed by sympathetic and parasympathetic functions of the autonomic nervous system.


FIGURE 13: Autonomic Nervous Function of the Cardiopulmonary System

The autonomic nervous system governs cardiopulmonary function in an oscillatory manner approximating the operation of the pendulum (FIGURE 13), inhalation being coincident with increasing heartbeat rate and exhalation with decreasing heartbeat rate. In this way, oxygen is transferred into the bloodstream upon inhalation and delivered rapidly throughout the body via an increasing heartbeat rate and increasing blood pressure. The converse is true upon exhalation. Upon consideration, it may be recognized that this relationship is ideal relative to the cardiopulmonary imperative, that being, the alternating supply of oxygen and removal of carbon dioxide from body tissues.(13) This ideal relationship, wherein cardiac and pulmonary efficiency and effectiveness are maximized, occurs at a specific frequency - that of resonance.(15)

The cardiopulmonary system is further detailed in FIGURE 14. Sympathetic and parasympathetic aspects function to govern the heartbeat rate and consequent blood pressure, as well as dilation/constriction of lung bronchi which function to alternately facilitate oxygen intake and carbon dioxide output.

logical block diagram of the primary physiological aspects of the cardiopulmonary system  

FIGURE 14: Logical Depiction of the Cardiopulmonary System

Motion of the diaphragm and intercostal muscles, which provide the mechanical action of breathing, is governed by both autonomic and somatic branches, the autonomic function facilitating the unconscious breathing process and the somatic function facilitating the conscious breathing process. The importance of this dual control is obvious, for without both autonomic and somatic control, either we would have no ability to breathe consciously, for example hold the breath, a function that is vitally important to survival, or we would have to breathe consciously 100% of the time!

Per prior arguments, the pendulum-like oscillator aspires to operate at a sinusoidal rhythm of 5 cycles in approximately 1 minute, i.e., the Fundamental Quiescent Rhythm . At this pace, sympathetic and parasympathetic functions are optimally balanced, the result being the optimized synchronization of the myriad of sympathetic and parasympathetic functions and activities throughout the body.

The ~12 second cycle, The Fundamental Quiescent Rhythm, depicted by FIGURE 15 below, consists of a sympathetic and a parasympathetic phase of activity.

depiction of the Fundamental Quiescent Rhythm and sympathetic/parasympathetic correlates

FIGURE 15: FQR & Sympathetic/Parasympathetic Correlates

The sympathetic phase manifests throughout the body as "activating", "accelerating", and "tensing". The parasympathetic phase manifests throughout the body as "deactivating", "decelerating", and "relaxing". Consequently, inhalation - activation of the diaphragm and intercostals ideally occurs coincident with the sympathetic phase, and exhalation - deactivation of the diaphragm and intercostals ideally occurs coincident with the parasympathetic phase. When exhalation occurs coincident with the parasympathetic phase, a "relaxation response" naturally occurs with each exhalation. (A key reason that people become "tense" is that this response is not elicited frequently.) In this way, autonomic balance and resulting homeostasis is achieved and maintained throughout the body at a 12 second rhythm.

Autonomic balance or lack thereof is a relative matter and for this reason it is best to conceive of it as a spectrum along which numerous psychophysiological factors lie. Research results published to date, corroborated by this authors own research and personal experience, suggest a broad spectrum of actions on the human organism. All of them appear to be of a desirable nature relative to overall health, well being, and performance. Generally speaking, the psychophysiological correlates of "balance" are those of "calm" and "relaxation" whereas those of "imbalance" are "stress" and "fight or flight".

physical comfort
physical tension
mind state
at ease
mind-body communication
free flowing
short term memory
sphere of awareness
openness to new ideas
interpersonal communication
serum pH
average heartbeat rate
blood pressure
heart rate variability
breathing rate

FIGURE 16: Psychological/Physiological Correlates of Autonomic Balance

Autonomic balance is not just about cardiopulmonary synchrony. It affects the entire organism! In The Heartmath Solution, the authors demonstrate that during the state of coherence, which is indicative of autonomic balance and cardiopulmonary resonance, the heart rate variability rhythm can clearly be seen to modulate brainwaves as measured by an electroencephalograph!(4) This author speculates that that the same is true of imbalance, but because it yields "incoherence" the EEG pattern is difficult to discern.

See the special report: Galvanic Skin Response, A Window Into Breathing and Autonomic Nervous System Function.

Achieving Balance:

Maximal autonomic balance with resulting maximal coherence requires that The Fundamental Quiescent Rhythm, as evidenced by the heart rate variability cycle, and the breathing rhythm be synchronized. Per FIGURE 15, this requires inhalation to occur on the positive going sympathetic phase of the autonomic cycle and exhalation to occur on the negative going parasympathetic phase.

Breathing frequency strongly influences sympathetic emphasis. Breathing depth strongly influences parasympathetic emphasis. When one breathes at the prescribed rhythm with appropriate depth, it results in autonomic nervous system balance and cardiopulmonary resonance. This relationship is depicted in FIGURE 17 below.

Figure 17: Breathing Frequency/Depth vs. Sympathetic/Parasympathetic Emphasis

Breathing rate strongly influences sympathetic nervous system emphasis, the higher the rate, the higher the sympathetic emphasis. Breathing depth strongly influences parasympathetic emphasis. Generally, the deeper the breathing the stronger the parasympathetic emphasis.

When breathing frequency is "Hi", by definition, depth is "Lo". This results in strong sympathetic stimulation and weak parasympathetic stimulation as depicted by the red quadrant.

When breathing frequency is "Lo" and breathing depth is "Lo", it results in low sympathetic stimulation and low parasympathetic stimulation, as depicted by the yellow quadrant. This condition is one wherein the breathing rate is not exacerbating sympathetic nervous system emphasis, but parasympathetic emphasis is not being elicited.

When breathing rate is "Lo" and breathing depth is "Hi", not only is the sympathetic function not being stimulated, but the parasympathetic function is strongly stimulated. As it is the objective to counter the tendency toward sympathetic over-emphasis, the net effect is autonomic nervous system balance.

With this in mind, there is a specific breathing frequency, with commensurate depth that yields optimal autonomic nervous system balance, this being the frequency of resonance.

There are 2 primary methods for achieving balance and cardiopulmonary resonance. The first method involves consciously synchronizing the breathing cycle with the actual heart rate variability cycle. This requires monitoring the heart rate variability cycle and synchronizing inhalation with accelerating heart rate and exhalation with decelerating heart rate. Any form of monitoring will work that allows one to clearly distinguish the accelerating phase from the decelerating phase.

The second method is based on a fundamental breakthrough, this being the fact that the intrinsic autonomic rhythm - The Fundamental Quiescent Rhythm, will synchronize with the breathing cycle if the breathing cycle is highly tuned with the natural frequency of the autonomic rhythm. In other words, if an adult in a resting or semi-active state simply breathes at the rate of 1 complete cycle (inhalation and exhalation) in ~12 seconds, the autonomic rhythm will align and "phase-lock" with the breathing cycle. With this, the optimal state of coherence is achieved and will persist as long as the breathing cycle persists at this rate. This second method is the basis of the COHERENCE Breathing Pacemaker(TM) series of audio-visual products.

In summary, COHERENCE asserts the following principles:

  1. While at rest, the adult cardiopulmonary system inclusive of central nervous system aspects, resonates at a specific frequency, 1 cycle in ~12 seconds – the Fundamental Quiescent Rhythm, this frequency being essentially the same for all adults.
  2. Human cardiopulmonary functions are organized to work most effectively and efficiently when in harmony with this rhythm.
  3. Operation at this rhythm is indicative of autonomic nervous system balance.
  4. Optimal autonomic balance - with optimal coherence, is a result of synchrony between the breathing cycle and this Fundamental Quiescent Rhythm.
  5. Rapid breathing while at rest results in autonomic nervous system imbalance, specifically a shift toward sympathetic emphasis. Increased heartbeat rate and decreased HRV amplitude are evidence of this shift.
  6. In a “healthy” individual, HRV amplitude is a function of breathing frequency and depth. Consequently, in a “healthy” individual, low HRV is indicative of suboptimal breathing.
  7. Because, while at rest, the average adult breathes at a rate of 10-20 breaths per minute, they exist in a state of persistent sympathetic emphasis.
  8. By breathing at the frequency at which the cardiopulmonary system (inclusive of central nervous system aspects) naturally resonates, one can achieve optimal autonomic balance and avert sympathetic dominance.
  9. It is desirable to achieve and maintain autonomic balance on an ongoing basis as life circumstances permit. This is the premise of COHERENCE, the company.

COHERENCE provides Breathing Pacemaker products for the purpose of synchronizing the breathing cycle with an external reference signal operating at the Fundamental Quiescent Rhythm of ~12 seconds, resulting in Coherent Breathing and optimal autonomic nervous system balance.

For those that are interested, much of this author's focus has been on the function of autonomic balance and coherence in the practice of yoga and meditation. These insights are shared in the evolving page, Yoga & Meditation.

Thank you for your interest.


1. Research on which this paper is based has been confined to a control group of 8 individuals. All measurements depicted in this document with the exception of FIGURES 3 and 8 are measurements taken on this author under differing breathing circumstances.


1. John D. And Catherine T. MacArthur Research Network on Socioeconomic Status and Health ( allostatic/notebook/heart.rate.html). Summary prepared by Ichiro Kawachi in collaboration with the Allostatic Load Working Group. Last revised 1997.

2. William Campbell Douglass, M.D., Stop Aging or Slow the Process, 2003, (ISBN 9962-636-37-X)

3. Anatomica – The Complete Home Medical Reference, 2001, Barnes & Noble, (ISBN-0-760728429)

4. Doc Childre, Howard Martin, The Heartmath Solution, 1999, (ISBN 0-06-251606-X).

5. D. Vaitl 1896, Author - R.I. Kitney, Cardiorespiratory and Cardiosomatic Psychophysiology, Heart Rate Variability in Normal Adults, Published by P. Grossman, K.H.L. Janssen, NATO ASI Series

6. Doc Childre, Rollin McCraty PhD. Psychophysiological Correlates of Spiritual Experience, Biofeedback (Winter 2001)

7. J. Pumpria, K. Howorka, D. Groves , M. Chester, J. Nolan, Functional Assessment of Heart Rate Variability: Physiological Basis and Practical Applications, International Journal of Cardiology 84 (2002).

8. I Antelmi M.D., R.S. Silva De Paula M.D.; A.R. Shinzato, C.A. Peres, A.J. Mansur M.D., C.J. Grupi M.D., Influence of Age, Gender, Body Mass Index, and Functional Capacity on Heart Rate Variability in a Cohort of Subjects Without Heart Disease, American Journal of Cardiology, February 2004, pg. 381-385.

9. H. Cammann, J. Michel, How to Avoid Misinterpretation of Heart Rate Variability Power Spectra, Computer Methods and Programs in Biomedicine 68 (2002).

10. M. Biagini, C. Cammarota, M. Prisco, F. Di Liberato, V. Fiori, P. Greziosi, P. Perelli, R. Romano, M. Lanza, Autonomic Nervous System Function Assessed By Analysis of Heart Rate Variability At Rest and During Exercise In Hypertensive and Normotensive Subjects, American Journal of Hypertension, Volume 17, Issue 5, Supplement 1, May 2004.

11. A.C. Guyton M.D., J.E. Hall PhD., Medical Physiology, 10th Edition (2000) ISBN: 0-7216-8677-X.

12. Sime, Wesley E., Phychophysiology of Stress and Relaxation, Department of Health and Human Performance, University of Nebraska-Lincoln,

13. Yasuma, F., Hayano, J., Respiratory Sinus Arrhythmia: Why Does the Heartbeat Synchronize with Respiratory Rhythm? - Opinions, Hypotheses, Chest - The Cardiopulmonary and Critical Care Journal, Feb. 2004.

14. D. Vaitl 1896, Author - Stephen W. Porges, Cardiorespiratory and Cardiosomatic Psychophysiology, Respiratory Sinus Arrhythmia: Physiological Basis, Quantitative Methods, and Clinical Implications, pg. 102. Published by P. Grossman, K.H.L. Janssen, NATO ASI Series

15. E. Vaschillo, B. Vaschillo, P. Lehrer, Heartbeat Synchronizes With Respiratory Rhythm Only Under Specific Circumstances, Chest - The Cardiopulmonary and Critical Care Journal, 2004.


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