Neuroscientist Professor Susan Greenfield says today's developing brain is being worryingly reshaped by excessive visual stimulation -- the effect of a culture driven by screens. Biotechnology, nanotechnology, even the internet are all impacting on our brains and could be heralding future generations with different abilities, agendas and even ways of thinking. Her prediction is that we might be standing on the brink of a cataclysmic mind-makeover never before seen...