“The positive effects of music seem to be linked to the fact that music causes neurons in the brain stem, a primitive part of the brain, to be activated in sync with the beat….. That has a cascade of chemical effects on the nervous system, typically evoking relaxation if the beat is slow and improving focus and alertness if the beat is faster.” —- http://www.cbc.ca/news/health/story/2013/04/01/health-music-as-medicine-levitin.html

No wonder playing the drums makes me so happy 🙂