Toronto (CP)Slaving over music scales is tedium incarnate for many children. But those who persevere may thank their lucky stars for it when they reach the other end of their lives.That's because music training, especially if it is commenced at a young age, may change the brain in ways that protect it against the ravages of time.That theory is being put forward by a team of Toronto-area researchers who will conduct a number of inter-related studies over the next three years to try to determine whether musical training protects the brain against dementia and other forms of cognitive decline in later life.Anne