Personal memories can be lost while the ability to communicate - or, for instance, play the piano - is not. One theory is that he has suffered a trauma which has caused amnesia, one of the methods the mind uses to retreat from a shock. Some who have heard the 'piano man', as he has been nicknamed, believe he may be a professional musician. Several weeks later he has still not spoken a word, expressing himself only through his music. Excited, hospital staff showed him into a room with a piano and he began to skilfully perform meandering, melancholy airs. He drew a detailed sketch of a grand piano.

It was only when someone in hospital had the bright idea of leaving him with a piece of paper and pencils that the first intriguing clue about the stranger's past emerged. Over the next few days he steadfastly refused, or was unable, to answer the most simple questions about who he was or where he had come from. Dripping wet and deeply disturbed, the smartly-dressed man was discovered walking along a windswept road beside the sea.

How to play amnesia on piano