This Simple Ancient Humming Practice has Multiple Benefits ~ John Douillard

Further Info:

https://lifespa.com/nitric-oxide-humming-brahmari-pranayama/

https://medium.com/@yelizruzgar/3-steps-to-spiritual-awakening-by-raising-your-brain-waves-to-gamma-11f93d66146a

http://www.berkeleywellness.com/self-care/preventive-care/article/why-nitric-oxide-so-important