" You don’t need that much quiet to change things, or even have to be alone. But you do have to seek out a soothing environment, and you must do it often. Japanese researchers at Chiba University found that a daily fifteen-minute walk in the woods caused significant decreases in cortisol, along with a modest drop in blood pressure and heart rate. Physiologists believe our bodies relax in hushed natural surroundings because we evolved there; our senses matured in grasslands and woods, and remain calibrated to them. "

― Michael Finkel , The Stranger in the Woods: The Extraordinary Story of the Last True Hermit