For instance, scientists have been using electrodes placed on the head to run a mild electrical current through the brain, a procedure known as transcranial direct-current stimulation (tDCS).Research shows that tDCS, which is painless, may increase brain plasticity, making it easier for neurons to fire.This, in turn, improves cognition, making it easier for test subjects to learn and retain things, from new languages to mathematics.Already there is talk of implanting a tDCS pacemaker-like device in the brain so recipients do not need to wear electrodes.A device inside someone’s head could also more accurately target the electrical current to those parts of the brain most responsive to tDCS.[Smart genes] would allow us to do so many different things.The sky’s the limit.Anders Sandberg, Oxford University’s Future of Humanity Institute

According to many futurists, tDCS is akin to an early steam train or maybe even a horse-drawn carriage before the coming of jumbo jets and rockets.If, as some scientists predict, full brain-machine interface comes to pass, people may soon have chips implanted in their brains, giving them direct access to digital information.