This is getting old, it really is. Will someone do a meta-study and discover that "mental activity stimulates brain," please? Then we can all cite that once and

This is getting old, it really is. Will someone do a meta-study and discover that "mental activity stimulates brain," please? Then we can all cite that once and for all. Whatever there is to say on this topic that's actually interesting has been said in "Everything Bad Is Good for You," a book I highly recommend.