I agree with what Doug says, that an electrically based estimate of consciousness or unconsciousness might be possible. And as a personal adjunct, it *might* (emphasize "might") be possible, using traditional external measures of brain wave activity, to "decode" (wrong term) EEG type signals to get very crude estimates of certain simple emotional states -- extreme anger, etc.
But speaking as a professional electrical engineer, part-time physicist and amateur neuropsychologist (an area of long-term interest and limited study though not of in-depth knowledge and experience) I will simply crudely assert with utter certainty that it is absolutely not possible, even remotely, for electrical sensors on the outside of the brain -- any number of them you choose, of any type (electrostatic, magnetic, electromagnetic) and sensitivity you can obtain -- to discern the content of conceptual thought via "brain waves" sufficiently to interpret those "waves" as language and transmit them to another person (as DARPA wants to) without the words first being spoken.
Without boring anyone with an essay, the interpretation of a state of consciousness is much more than a word or phrase measured in the moment, and the physical state pertaining to consciousness is much more than electrical emanations escaping the brain. It's much less possible to discern the content of consciousness from an array of external electrical sensors than it is to follow the total sequence of calculations in a computer with an array of electrical sensors. To be less ambiguous, the possibility in either case is simply, zero.
That DARPA doesn't realize this either means A) this is just a ruse to conceal funding of much more practical activities (a common ploy), or B) they haven't a clue. Speaking from personal experience, I strongly recommend (B). In all matters pertaining to the functioning of government, the operative principle most likely to lead one to the truth is: if it looks stupid, it probably is. In the vernacular of Forrest Gump, stupid is as stupid does.
While telepathy is nonsense, there is one portion of the article which might touch on valid research. (I emphasize 'might'.) "The project has three major goals, according to Darpa. First, try to map a person’s EEG patterns to his or her individual words. Then, see if those patterns are generalizable — if everyone has similar patterns. Last, “construct a fieldable pre-prototype that would decode the signal and transmit over a limited range.” There is a now a monitor in the operating room which sums the electrical signals form the brain and converts that sum into an estimate of the patient's level of consciousness. Some anesthesiologists use it to monitor the level of conciousness to make sure that the patient is 'asleep'. (In my view, at the current state of the technology which does have errors in its estimates, it is no more valid than the customary approach.) But it does suggest to me that trying to find out if one can relate specific electrical signals from the brain to a specific thought might be a valid pursuit. A neurophysiologist would know better.
Why DARPA is a joke ...
Pentagon Preps Soldier Telepathy Push
Forget the battlefield radios, the combat PDAs or even infantry hand signals. When the soldiers of the future want to communicate, they’ll read each other’s minds.
At least, that’s the hope of researchers at the Pentagon’s mad-science division Darpa. The agency’s budget for the next fiscal year includes $4 million to start up a program called Silent Talk. The goal is to “allow user-to-user communication on the battlefield without the use of vocalized speech through analysis of neural signals.” That’s on top of the $4 million the Army handed out last year to the University of California to investigate the potential for computer-mediated telepathy.
Before being vocalized, speech exists as word-specific neural signals in the mind. Darpa wants to develop technology that would detect these signals of “pre-speech,” analyze them, and then transmit the statement to an intended interlocutor. Darpa plans to use EEG to read the brain waves. It’s a technique they’re also testing in a project to devise mind-reading binoculars that alert soldiers to threats faster the conscious mind can process them.
The project has three major goals, according to Darpa. First, try to map a person’s EEG patterns to his or her individual words. Then, see if those patterns are generalizable — if everyone has similar patterns. Last, “construct a fieldable pre-prototype that would decode the signal and transmit over a limited range.”
The military has been funding a handful of mind-tapping technology recently, and already have monkeys capable of telepathic limb control. Telepathy may also have advantages beyond covert battlefield chatter. Last year, the National Research Council and the Defense Intelligence Agency released a report suggesting that neuroscience might also be useful to “make the enemy obey our commands.” The first step, though, may be getting a grunt to obey his officer’s remotely-transmitted thoughts.