Professor Jane Raymond, Professor of Visual Cognition at the University of Birmingham, says: “Most people trust their banknotes, are usually in a hurry, and often handle cash in places where the lighting is bad. The big problem is that the security features on most banknotes from around the world only work well when people slow down and look carefully at them under good light. So, in lots of situations, it not so hard to miss a fake banknote. Security features need to give people fast, easy-to-see signals that work under all sorts of lighting conditions.