Imagine not recognising your mother when she walks past you – not because you can’t see her, but because you can’t distinguish her face from the thousands that you come across every day. This lecture is a glimpse into the fascinating world of prosopagnosia, or ‘face blindness’, and the challenges it poses to people living with the condition – and those close to them. While brain damage is known to cause prosopagnosia, recent discoveries show that it can also come about if people fail to develop the necessary neural processes. These individuals have never suffered any damage to their brain and astonishingly some of them have no problem recognising objects. Now consider what it is like when this condition runs in families and what is actually going on in the brain to bring about this remarkable condition.Lecture given on 19 October 2006