How to talk when you can't speak: My latest Slate column
Last week, a report in Neurology outlined some rather disturbing findings: Apparently, supposedly "minimally conscious" brain-injury patients may be far more conscious than we realize. The scientists located two men who'd suffered terrible brain injuries, leaving them able to breathe on their own but otherwise unresponsive. Then the played them audiotapes of their loved ones relating cherished stories from their past. The result? The men's brain activity was amazingly close to that of "normal", fully-conscious people -- and one of the men even had high levels of visual-cortex activity, indicating that he was perhaps visualizing the memories. If this study holds water, we may need to radically rethink how we deal with the minimally conscious -- who are often abandoned and left with almost no stimulus.
Better yet, is there any way to communicate with them? This is the subject I tackled in my latest Slate column, where I looked at the state of "brain computer interfaces". An example:
One promising technique for unlocking the thoughts of paralyzed patients is to hook them up to electroencephalograms. EEGs read the electrical impulses caused by brain activity, including the "P300 wave," something like an involuntary "aha" response. When you're looking at a set of items and see something you suddenly recognize, your brain automatically kicks out an electrical spike 300 milliseconds later. You don't have to think about it; it just happens.
Psychologists Lawrence Farwell and Emanuel Donchin have turned this response into a rudimentary typing machine. The patient gets hooked up to an EEG, then looks at a computer screen that shows a six-by-six grid of the letters of the alphabet. When he focuses on a certain letter, the computer begins highlighting each column. As the column containing the chosen letter comes up, the subject's brain spits out a P300 "aha" response. When the computer repeats the same thing with the rows and gets another "aha," it gets the X and Y coordinates for the correct letter. Using this technique, people with ALS can "type" about four letters per minute. Best of all, because the "aha" response happens automatically, they don't have to learn any new skills.
You can read the rest of the piece online here for free -- and if you've any thoughts on it, feel free to post in The Fray, Slate's comment area, where intelligent discussion is always welcome!
Posted by Clive Thompson at February 15, 2005 01:38 AM
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I haven't read the piece yet -- I'm responding to your word "disturbing."
Need I point out that for anyone who has a loved one in a coma or some state similar to that, this is fabulously good news? This is what you hope is happening. Isn't it? I guess being trapped inside a lifeless body could be pretty bad, hellish, etc. -- but when you stand over your comatose bride, groom, mother, son-- you're hoping he or she hears and understands you.
Right?
Absolutely, that makes sense! However, my use of "disturbing" was intended to refer to the fact that a great majority of the minimally-conscious are presumed to be in a vegetative state, and are left with no stimulation at all. If they're actually more conscious than that, this is tantamount to horrid neglect -- and is indeed quite disturbing.