On the healing powers of singing
Excerpt of an article by Mads Elung-Jensen for the American Blog Radical Virgo
The number of skeletal muscles in the human body varies from about 656 to 850, depending on which expert you consult. But only one set of muscles in the human body, the vocal folds, commonly known as the vocal chords, is not controlled by the conscious brain. Phonation is controlled by the vagus nerve. Besides outputs to the various organs in the body, the vagus nerve conveys sensory information about the state of the body's organs to the central nervous system. It also acts to lower the heart rate.
So, when you speak and when you sing, you do it always by activating unconscious reflexes and impulses. But while speaking involves involuntary diaphragm usage primarily, singing involves voluntary diaphragm usage.
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