Geoff Lean was in a coma for a month, during this time he could hear and feel everything but it wasn't until he woke up from the coma that he realised he had also unconsciously absorbed visual information through his eyes.

Aleks investigates Blindsight, one of the most curious phenomenon's in cognitive neuroscience and helps to explain how Geoff was able to see without seeing. Milena Cunning went into hospital a sighted person but when she awoke from a coma her world was completely black. A stroke had destroyed the part of the brain that allowed her to see, she later discovered that she had Blindsight. A condition which results in a loss of visual experience yet allows information unconsciously to reach the brain. It suggests there is a great deal that we are doing independently of consciousness awareness. We are able to automatically perform without conscious sight or thought. This is highlighted when we become familiar with a piece of technology it becomes automatic, we need little conscious input to use it.

Aleks discovers we are able to steer our way through the world on auto pilot especially if we are performing a habit, an automatic behaviour stored in our unconscious. We all experience a form of Blindsight, like driving and having a conversation , our attention is on the conversation, so we are not conscious of actually driving. Our automatic use of the technology, the car, is stored in our unconscious mind.

Professor Nillie Lavie from UCL says that what Blindsight shows us about our ability to unconsciously see coupled with how we are presented with information online influences not only how much we are subliminally influenced in a digital world but the type of information we unconsciously pick up on and absorb.

Produced by Kate Bissell.