A question: can you predict Alzheimer's by a careful analysis of someone’s writing? An English professor has suggested there are tell-tale signs of early Alzheimer's in Agatha Christie’s book, Elephants Can Remember. AFP/Getty Images hide caption

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Magritte's 1964 painting The Intimate Newspaper gets us thinking: Who is this? A familiar friend or a complete stranger? Rene Magritte/Corbis hide caption

itoggle caption Rene Magritte/Corbis