"There's more deactivation of the DLPFC during happy improvisations, perhaps indicating that people are getting into more of a 'groove' or 'zone,' but during sad improvisations there's more recruitment of areas of the brain related to reward," said McPherson, a classical violist and first-year graduate student in the Harvard-MIT Program in Speech and Hearing Bioscience and Technology. "This indicates there may be different mechanisms for why it's pleasurable to create happy versus sad music." - http://www.sciencedaily.com/releases/2016/01/160104080022.htm