Bright sparks: could bioelectricity make us smarter and healthier?

Electricity is involved in every aspect of life. But could the new science of bioelectricity help cure diseases and upgrade' humans?

I was back at the checkpoint. The traffic moved as normal. Bored-looking soldiers waved through civilians on foot, dusty cars and rickety trucks full of livestock and produce.

Then the Humvee in front of the gate blew up. Out of the eye-searing blast, I made out the figure of a man running at me, full-speed. He was wearing an explosive vest. I shot him.