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Non-Invasive Computer Control Through Brainwaves
mikael writes "An article on the BBC website is reporting that U.S. scientists have managed to develop a 'thinking cap' which allows a computer to receive commands from the electrical activity of a person's brain alone. Comprised of 64 electrodes, this cap allowed two users to control a cursor through pure thought alone, rather than through eye movements or other physical gestures." Unlike some previous efforts, this one doesn't require anything to be implanted in your brain.
My wife (working on her PhD in psychology) was part of a program where children diagnosed with Attention Deficit Disorder would play PlayStation games with a special controller in order to teach them how to strengthen their focusing skills.
The controller was tied to a machine which monitored the level of a certain brainwave (I don't remember which) and if the levels fell outside predetermined parameters the controller would cease to function properly. This helped teach the kids how to maintain focus while performing a task that required constant attention. The 'brain interface' part looked like a baseball cap with lots of little sensors inside, no neurosurgery required.
I tried it myself (I do not have ADD) and it was interesting how difficult it seemed at first to 'grasp' the required level, and how second hand it became after a few minutes of play (obviously the patients took quite a bit longer). It was a neat alternative / addition to drug therapy. I'd bet there is a lot of value in this more accurate control interface for future treatment.
The work is pretty neat. They put a sock thing on your head and measure your brainwaves. Apparantly not everyone can be trained to use the system. There was a long screening process where they looked for people with brain patterns that they could read. I signed up for the screening but I was never called; I guess they got all the volunteers they needed. My friend went in for the screening; they make you wear the reader thing on your head while you concentrate on a dot moving through a very simple maze. Evenutally you get to try to control the dot; that's as far as my friend reached. I know that eventually they move you up to an actual "Armitron" toy that they wired up to the monitors. It is very cool research.
This stuff isn't geared to replacing your keyboard and mouse. The hook is the promise of developing the technology for better artificial limbs; but think about it. If a disabled person can control their own artificial arm with brainwaves; why not a big crane? Why not a crane on a battleship or out in orbit?
(Jonathan R. Wolpaw and Dennis J. McFarland. Control of a two-dimensional movement signal by a noninvasive brain-computer interface in humans. PNAS published December 7, 2004, 10.1073/pnas.0403504101)
From the methods and diagrams in the article looks like the slower mu oscillations moved the cursor in the horrizontal axis and the vaster beta osicllations moved the cursor in the vertical axis.
2^5
Actually, there are 128 electrode arrays, which are used quite frequently in cognitive neuroscience research. (see here for example.) However, they take longer to put on (you have to make sure each electrode makes a good connection with the scalp) and the increased spatial resolution (which is minimal since signal is quite smoothed by going through the skull) is not necessary for an application like this one.
This is not new, by the way. There were some studies done back in the early 90s using only two electrodes where people learned to move a cursor around on a screen. Just one on the left hemisphere and one on the right, and you hook it up so that different relationships between the activity at the two sights controls the different parameters of movement on the screen.
See Wolpaw, JR., McFarland DJ, Neat GW, Forneris CA. An EEG-based brain-computer interface for cursor control. Electroencephalogr Clin Neurophysiol. 1991 Mar;78(3):252-9
Have you ever just had fun playing with your brain?
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If you do it right you can trick your brain into thinking you have another limb or two.
I recall seeing a documentary about a doctor that cured a patient of problems with a "phantom" limb. The patient had lost a hand, had problems with feeling as if it was still there, but in an uncomfortable position. The doctor fixed it by making a simple box that created a mirror image of the missing limb, and telling the patient to place his hands in the box. The mirror image tricked the patient's brain into thinking the hand was still there and allowed him to move it around. Here's a link I found.
There was also some connection between missing limbs and tactile senses on other parts of the body. Apparently, the human body maps onto the surface of the brain. In some cases, when people lose a limb, the unused sensory area on the brain gets confused with nearby areas that correspond to different parts of the body. Here's a link.
As for what you are talking about - tricking the brain about your limbs - there is some mention of that as well.