I missed it when the press ran with it earlier this year, but thanks to the Star Trek website, I’m up to speed on Air Force efforts to substitute electricity for caffeine. The intent is to use mild (and the emphasis should be on mild) electric shocks to keep airmen and women alert and attentive.
Efforts are still quite preliminary, but research scientists interviewed have claimed that noninvasive stimulation of the right areas of the brain have enabled subjects to respond better cognitively than a control group that had been awake for comparable amounts of time. The techniques used are taken from electrical stimulation procedures used for some psychiatric conditions. (The levels of electricity are much, much lower than what had been used in so-called electroshock therapy. At 1-2 milliamperes, the shocks are just perceptible.)
One challenge the researchers still have to address is determining which areas of the brain need stimulation in order to achieve the increased alertness and cognitive function. The research has focused on subjects who work in persistent data monitoring, and researchers are optimistic that a working device may be achievable in five years or so. Whether or not something like this could (or should) be available commercially is a question for another day.