Technical Terms - Glossary

Achievement Score: Is the sum of your individual Coherence Scores, tabulated during the length of a session.
Click here to learn more about achievement scores.

Heart Coherence: Coherence refers to your internal order or harmony. Increased Coherence enables better internal balance, greater health, and new levels of creativity, resilience and productivity.

Coherence Score: A measure of the degree of Coherence in the heart rhythm pattern. A Coherent heart rhythm is a stable regular repeating rhythm resembling a sine wave at a single frequency between 0.04-0.24 Hz (3-15 cycles per minute). The scoring algorithm continuously monitors the most current 64 seconds of heart rhythm data and updates the score every 5 seconds.

The more stable and regular the heart rhythm frequency is, the higher the Coherence Score. Scores range from 0-16. With practice and regular use you will begin to notice your normal Coherence Score level and how it fluctuates when you have more or less focus and when you experience greater levels of inner balance. Use your score range as your guide to setting the Challenge Level and Achievement Goal.

Coherence Score Guide

0.5	Basic – good beginner level
1.0	Good
2.0	Very good
3.0+	Excellent

Challenge Level: These settings are thresholds for the levels of Coherence that determine if you are in low (red), medium (blue) or high (green) Coherence. There are four different Challenge Levels; 1, 2, 3, and 4. As your Coherence Score rises you shift from one range (low, med or high) to the next. The Coherence Score threshold between the three ranges is gradually increased at a rate of 15% for each higher Challenge Level 1 ‐ 3 and 30% between 3 ‐ 4. The following table and figure shows the threshold setting for each Challenge Level. Coherence and Achievement Scores are not affected by the Challenge Level Setting.

Coherence Over Time: A graphical display that charts your Coherence Scores over the entire length of the session. The chart is updated every 5 seconds with each new score. The background of the chart reflects the Coherence Level Thresholds for the current Challenge Level Setting; red = low, blue = medium, green = high. When you achieve higher levels of Coherence Scores, the plot window will auto scale and the red and blue portions will get smaller.

Coherence Ratios: A session summary of the amount of time, as a percentage of the total session length, in each of the three Challenge Level ranges. For example, in the session below the Coherence Ratio Display shows 48 low, 29 medium, and 23 high. This score will be affected by your challenge level settings.

Coherence Technique: Click here to understand, review and practice the Quick Coherence Technique.

Heart Rate Variability (HRV):  The normally occurring beat-to-beat changes in heart rate. Analysis of HRV is an important tool used to assess heart-brain interactions and autonomic nervous system dynamics (function, synchronization and balance). HRV is considered a key indicator of aging, cardiac health, resilience and overall well-being.

Power Spectrum: A mathematical transformation of the heart rhythm data into its frequency components. The slowest (low) frequencies are shown on the left hand side of the graph and faster (high) frequencies on the right. As the heart rhythm becomes more Coherent the frequency distribution becomes more concentrated into a signal peak. The Spectrum is updated every 5 seconds.