Susan Greenfield, Baroness Greenfield, (born Hammersmith, London, 1 October 1950) is a British scientist, writer and broadcaster. She specializes in studying how the human brain works and has done a lot of research into diseases such as Parkinson's disease and Alzheimer's disease which are common in older people. She has written several books and appeared frequently on radio and television. She is very good at explaining what she does to the wide public, using words that ordinary people (non-scientists) can understand. In 1994 she gave the series of Christmas lectures on television for young children.