Sure. Certain findings seem pretty consistent, whether from Heartmath or other people. Negative states of mind are associated with low heart rate variability, meaning that the heart does not have the normal responsiveness to situations and demands, changing as needed. Positive states of mind are associated with higher HRV, and doing HRV biofeedback increases positive states of mind. In fact, I read a book, I think by Childers in which he recommended some steady breathing technique (that increases HRV) coupled with focusing on thoughts of love towards someone. the combination had the strongest effect on increasing HRV (which is physiologically good), and is pretty much like loving-kindness meditation.
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