Every time you share a pint with a pal, win the lottery or have sex, a liquid chemical floods the brain, stimulating the grey matter scientists link to feeling good and a sense of reward. And, if you are Canadian, chances are the same thing happens when you hear the former theme song of CBC's Hockey Night in Canada. At least, that's one scientific way of explaining why nearly an entire nation expressed such deep loss when the public broadcaster dropped "Canada's second national anthem" after a weekend battle of copyright chicken. "I think Canadians have actually bonded to the song. They've experienced enough of a chemical reaction to it," says McGill neuroscientist Daniel Levitin. "I don't mean to make this sound spooky or mystical, but we know that when people hear music they like, and are familiar with, dopamine is released."