Our brains allow us to see things in a certain fashion because of the way they process information. If we were fish, we'd see things complete differently, we'd have no perception in three dimensions, we'd see in black and white and we'd be able to see all around us - but not to the front!

Flies, on the other hand, can only see things that move - or that are moving in relation to them, and a cobra can see a living thing in total darkness as it sees using infra red - it's quite frightening to think that it can strike its prey with absolute accuracy in total darkness!

The Brain Illusion Teaser is a series of tricks to catch your brain out and illustrate that what you think you see is not always correct. Guillaume puts a great deal of preparation into his lectures to make them memorable occasions, using 3D spectacles, sound and vision to illustrate his subject. "Giving students a full show is the best way to help them to remember what I have to say," he says.