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The tailor as hacker

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!


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Bio:

I'm Clive Thompson, the author of Smarter Than You Think: How Technology is Changing Our Minds for the Better (Penguin Press). You can order the book now at Amazon, Barnes and Noble, Powells, Indiebound, or through your local bookstore! I'm also a contributing writer for the New York Times Magazine and a columnist for Wired magazine. Email is here or ping me via the antiquated form of AOL IM (pomeranian99).

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