The human brain is still largely an unsolved mystery. We only marginally understand how it works and are even less able to predict how it will behave in certain situations. One of the most frustrating of those situations is the coma. Anecdotes abound of people in comas who unexpectedly wake from them, much to their doctors' surprise. But what if doctors could get ahead of that surprise with a predictor of whether or not a patient will regain consciousness? A team of Belgian scientists have proposed just such a clue.