‘Yogic Breathing Helps Fight Major Depression, Penn Study Shows – Controlled Breathing Practices Show Promise in Patients Who Don’t Fully Respond to Antidepressants’, http://www.uphs.upenn.edu/news/News_Releases/2016/11/sharma/, Penn Medicine, University of Pennsylvania (NOVEMBER 22, 2016).

Rhythm-specific breathing

A promising, lower-cost therapy that could potentially serve as an effective, non-drug approach for patients battling this disease. (…)  The meditation technique, which is practiced in both a group setting and at home, includes a series of sequential, rhythm-specific breathing exercises that bring people into a deep, restful, and meditative state. (…) The next step in this research is to conduct a larger study evaluating how this intervention impacts brain structure and function in patients who have major depression.