I think play and joy and feeling good deserve more of our time. I don't see why adults are supposed to grow out of those things. If I have a mission it's to make everyone who comes to my concerts leave feeling a heightened sense of freedom to play, sing, and enjoy themselves.
The process of creativity, absorbing aspects of life and channeling it into something shared or tangible - that's my ideal brain food. The irony to this is that the more creative I have became, the less I listen to of other peoples music.