The answer is 12. 12 great.
Great "Seed Session", with David Byrne (a musical genius, up there with Stevie in the hero rankings) and Prof. Daniel Levitin (used to be a session musician and sound engineer, but now is James McGill professor of behavioral neuroscience and music at McGill University) having a good old natter about the neuroscience of music and all dat wicked shit man...
DB: So when you watch a performance, sports for example, you're not only watching somebody else do it. In a neurological kind of way, you're experiencing it.
DL:Yeah, exactly. And when you see a musician, especially if you're a musician yourself--
DB: —air guitar.
DL: Air guitar, right! And you can't turn it off—it's without your conscious awareness. So mirror neurons seem to have played a very important role in the evolution of the species because we can learn by watching, rather than having to actually figure it out step-by-step.