The brain is constantly being bombarded with information, so how does it decide what to trust and what to ignore, without the person even being aware of it? Professor Bruce Hood gives the second of this year's Christmas Lectures - testing the limits of the memory, finding out how humans learn, how the brain takes shortcuts and why multitasking can be dangerous. Bruce makes people say the wrong thing and fail to see what is right in front of them. Can one really believe one's eyes? Possibly not. Show less