Blink: A Horizon Guide to the Senses

Touch, sight, smell, hearing and taste - our senses link us to the outside world. Dr Kevin Fong looks back through 40 years of Horizon archives to find out what science has taught us about our tools of perception - why babies use touch more than any other sense, why our eyes are so easily tricked and how pioneering technology is edging closer to the dream of replacing our human senses if they fail. (BBC FOUR)