Literature student turned neuroscientist, Prof David Eagleman, tells Jim Al-Khalili about his research on human perception and the wristband he created that enables deaf people to hear through their skin. Everything we see, taste, smell, touch and hear is created by a set of electro-chemical impulses in the dark recesses of our brain. Our brains look for patterns in these signals and attach meaning to them. So in future perhaps we could learn to ‘feel’ fluctuations in the stock market, see in infra-red or echo-locate like bats? Each brain creates its own unique truth and David believes, there are no real limits to what we humans can perceive.