Thursday, March 10, 2011

# 6 What is “Coherence” and how does the emWave™ or StressEraser™ measure it ?

Coherence is a tricky concept to master because it is used in several different ways in the literature of HRV.  To facilitate understanding I’ll explain “coherence” from the perspective of someone opening up and beginning to use an emWave/StressEraser.

Auto-coherence of the Heartwave. – Breathing deeply and rhythmically, the display of the heart-rate will be a smooth, regular, undulating wave.  A  “sine-wave”.

Given it’s regularity the parts of the wave are all “organized, consistent, and logical” with each other.  It is coherent with respect to itself, or “auto-coherent”.  The HRV device calculates exactly how regular or “auto-coherent” the waveform is.  This gets represented as low (red on the emWave, one box on the StressEraser), medium (blue/two boxes) or high (green/three boxes) “Coherence”.  Achieving “High Coherence” (Auto-coherence) means that there is the potential to achieve other types of Coherence that have profound effects on the mind and body. But you’re not there yet.

Physiological Coherence-The body contains many oscillators, that is, systems that cycle.  For example the heart beat, breathing, blood pressure and brain waves. When two or more systems are synchronized they are said to be “coherent”. When many systems in the body are synchronized the person is in a state of “physiological coherence”.  To achieve this state takes ten to twenty minutes for most people beginning to use HRV.  Why?

Imagine a middle school orchestra.  If the conductor  keeps regular time (auto-coherence) then as the orchestra continues to play, the instruments will fall into synch.  The drums get in synch with the conductor which helps the bass get in synch  which helps the strings get into synch etc. until the entire orchestra is synchronized or “coherent”.

In the body, the heart and respiration get in synch which then allows the pressure sensitive baro-receptors to get in synch which then allows the brain (thalamus and cortex) to get in synch.  This is a sequential process that occurs over time.

Individual Coherence- After Physiological coherence has been achieved it is possible to see the manifestations at the behavioral level.  The person is more “coherent” –e.g. ideas are expressed more clearly, actions are more fluid and take less energy, and life in general proceeds more smoothly.

Take Home Point. – When you start to score “High Coherence” in an HRV session your mind-body is not yet in a state of “Coherence”.   If you continue to score “High Coherence” and allow the different “players” in your body to sequentially get in synch over ten to twenty minutes you will then be in the “Coherent” state.  And you will know that not because of a score, but rather because of how you feel.

1 comment:

  1. Yes. Yet feelings being subjective it's a bit of a slippery slope sometimes. As a practitioner and hrv emwave user I see this regularly. Great post though. One point I'd like to suggest. A flaw w Heartmath is rating our hrv as if red is bad, green is good has been somewhat of an issue. People need to feel successful, especially kids.. so I've altered the descriptions to red means some excitement and green less exciting yet healthful calm. That has helped A LOT! :) I know the post wasn't about that, just wanted to add it while here..