Those of us who follow science fiction have heard of this. Its called "wireheading", and originally it was conceived of as a means of recreation, directly stimulating the brains pleasure centers with electrical current. Of course, that is not quite the same intention here, but the same principle applies. If you could become better at math or science by hooking up a couple of electrodes to your brain every other day, I think most people would do it, and many would abuse it. But what you are speaking of seems to be some form of linguistic test, I assume their were others done, though I am curious why you left out those studies.
I see no reason why this couldn't be used to treat depression, or why further study shouldn't be done with other neurological disorders. I could see someone using this as accelerated learning programs become more common. Perhaps even the treatment of addiction might benefit from a mild dose of stimulation. There don't seem to be any long term side-effects, and I think scientists occasionally have to take risks if they want to make discoveries. All we need are a few people willing to see the potential in these studies.
Lots of interesting things coming out of Bethesda these days. It seems to be a popular name as well. Too often it seems as though the brain is something we are better off not knowing about, we approach the subject with cation because we are afraid that what we learn might in some way make us aware as to the limits of our minds potential. Will we be able to cope if the brain turns out to be an antiquated piece of biological hardware? Will there be other means of unlocking the minds potential outside of trying to study the brain piecemeal, trying to connect the dots when one area lights up green and another orange?
I would hope so. Knowledge is not the bogeyman it is so often made out to be in Christian fairy tails, though it does have its consequences. (Ever heard of the rational ignorance principle?) There are so many parts of the brain that remain dormant, relative to areas such as our motor control centers, the strange duality between the right and left lobes of the brain, how one seems to favor creative thinking and the other logical thought. The frontal lobe, linked to perception, and the ever-present medula-oblingata, a word that is as fun to study as it is to say, which i am told is related to regulating aggression.
Perhaps Bethesda should be on the look out for some of that grant money that is being approved by our congress.