The man who forgot how to read and other stories.

World renowned neuroscientist Oliver Sacks has recently been diagnosed with a tumour behind his eye and has admitted for the first time that he has problems with face recognition, a problem which has been lifelong. In this programme, Alan Yentob discusses facial recognition with Sacks and they look at other people with the same condition. Portrait artist Chuck Close describes what it's been like having face recognition problems for his entire life. Yentob also meets crime writer Howard Engel who woke up one morning to find he could no longer read or recognise written words although he could still write. It became clear that he had had a stroke which had irreversibly damaged the word recognition parts of his brain, however he has taught himself to read in a painstaking new way by drawing the pattern of the letters with his tongue inside his teeth. The programme includes some archive footage of earlier Sacks programmes, including his study of Danny who was born with Usher Syndrome, a condition which meant he was born deaf and would gradually lose his sight. Yentob goes to meet him today to see how his condition has progressed. We see how people with neither sight nor hearing can learn to communicate with tactile sign language. Neurobiologist Sue Barry has only recently been able to perceive things in three dimensions as she was born without stereo vision, which she acquired suddenly in her forties. Following treatment for his tumour, Sacks has lost his stereoscopic vision. He speaks movingly about how this loss has affected him.