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Reached Via a Mind-Reading Device, Deeply Paralyzed Patients Say They Want to Live (technologyreview.com)

Posted by msmash on from the groundbreaking dept.

Neuroscientists have designed a brain-reading device to hold simple conversations with "locked-in" patients that promises to transform the lives of people who are too disabled to communicate. Details of four patients who were able to communicate using what is being touted as a groundbreaking system were made public this week. From a report on MIT Technology Review: Now researchers in Europe say they've found out the answer after using a brain-computer interface to communicate with four people completely locked in after losing all voluntary movement due to Lou Gehrig's disease, or amyotrophic lateral sclerosis. In response to the statement "I love to live" three of the four replied yes. They also said yes when asked "Are you happy?" Designed by neuroscientist Niels Birbaumer, now at the Wyss Center for Bio and Neuroengineering in Geneva, the brain-computer interface fits on a person's head like a swimming cap and measures changes in electrical waves emanating from the brain and also blood flow using a technique known as near-infrared spectroscopy. To verify the four could communicate, Birbaumer's team asked patients, over the course of about 10 days of testing, to respond yes or no to statements such as "You were born in Berlin" or "Paris is the capital of Germany" by modulating their thoughts and altering the blood-flow pattern. The answers relayed through the system were consistent about 70 percent of the time, substantially better than chance.

10 of 180 comments (clear)

  1. Seventy Percent by Anonymous Coward · · Score: 5, Insightful

    Sorry to be the skeptic, but 70% of the time isn't really that high. it means that the machine can read your thought 40% of the time and then the remaining 60% is a coin flip.

    And this assumes no biases introduced into the process. We've seen in the past that ways of reading a paralyzed persons thought have turned out to either be scams, or well-intentioned people unconsciously affecting the results of the readings.

    Now, I really hope we find ways to accomplish what this researchers are claiming, but I am skeptical.

    1. Re:Seventy Percent by omnichad · · Score: 5, Insightful

      it means that the machine can read your thought 40% of the time and then the remaining 60% is a coin flip.

      That's not how probabilities work. It's true that it's better by 20% than a coin flip, but the rest of your conclusions are completely wrong.

    2. Re:Seventy Percent by Immerman · · Score: 3, Insightful

      True, but frequency ordering would get horribly tedious fast. Something more like a binary tree would be much more efficient - you can identify any letter in the alphabet with only 5 yes/no questions: Does the next letter come before N? - yes. Before H? -no Before K? -yes Before I?-yes Your letter is H. Next letter...

      Of course with a binary search you *always* need to answer log2(N) questions (or one less, if you for a non-power-of-two number of options), and we could do much better using an unbalanced tree where the most frequently used letters required answering fewer questions.

      Probably you'd want to navigate something like a static Huffman coding tree. As I recall (can anyone confirm?) an optimal coding of US English averages around 2.5 bits per letter, so on average you'd only need about 15 answers per six-letter word. For added convenience you could also add one or more "escape characters" to allow fast access to a palette of common phrases.

      It never ceases to amaze me how crude many such communication devices are. I could understand doctors ignoring decades of information theory as outside their field of expertise, but the programmers who actually write the software have no excuse. I mean yes, there's going to be a learning curve as you learn your way around your Huffman tree, but if you're stuck communicating through a computer for the rest of your life, I'd think it would be worth the effort. Though I could understand picking something a little suboptimal just to avoid running into those 13+bit letters in the middle of a sentence.

      And of course, if your equipment can distinguish between more than just two states, most such encoding trees can be trivially extended to 3- or more-way trees to drastically reduce the average number of nodes you need to traverse

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
  2. Interesting, but I'm not sure I trust it by scubamage · · Score: 4, Insightful

    This is neat research, but I want it much more strongly vetted. It reminds way too much of the facilitated communication mess we encountered several years ago.

    1. Re:Interesting, but I'm not sure I trust it by Anonymous Coward · · Score: 5, Insightful

      As they hooked up the device and turned it on, I felt an immense sense of relief. Finally, after all these years of staring at the bleak beige ceiling tiles.

      "Do you want to live?" the doctor asked.

      In my mind, I shouted, "No!" No! A million times no! Release me from this dead body so that I can move on to the summerland! No! Let me die!

      The doctor turned to my wife and told her, "He says that he wants to live! We should be able to keep him alive for another good 30 years."

      I can't move my mouth, and I must scream.

    2. Re:Interesting, but I'm not sure I trust it by MBGMorden · · Score: 4, Insightful

      You say that as someone who isn't enduring it.

      To many people anything less than what they have now is completely unbearable. To the rich they think if they were poor they'd kill themselves - despite many poor people living happy lives. To the young many think that they'd rather die than grow old - even though "old" is a moving target that keeps getting a little farther out as you age.

      The will to live is strong - those without it don't pass on their genes as readily. Don't presume to know whether they'd want to live unless you're in their situation.

      --
      "People who think they know everything are very annoying to those of us who do."-Mark Twain
    3. Re:Interesting, but I'm not sure I trust it by Anonymous Coward · · Score: 2, Insightful

      Personally I'd rather I get results from a scientific study than creative writing . . .

  3. Re:Harsh by Anonymous Coward · · Score: 2, Insightful

    Eh, RepublicanCare ("The World's Greatest Health Plan") will go more like this:

    Doctor: Do you have money to pay us for keeping you alive?
    American patient: Yes
    Doctor: Okay, this one can live. Follow up in one week for repeat testing.

  4. Re:Success rate by AthanasiusKircher · · Score: 3, Insightful

    70% doesn't seem high enough to make any decisions.

    To make legal decisions on care or something? Probably not. But it MIGHT be evidence that we're on the right track to communication.

    And how was this controlled for confirmation bias, like has been discredited for other techniques where the person that reads the results also knows the answers, like e.g. dog training and lie detectors?

    This is a valid question. I skimmed the actual study, but I don't have time right now to dig through the jargon and see how much these results are likely to be due to confirmation bias.

    Here's the actual study. Does someone who knows more about these sorts of measurements want to sort out whether or not there were adequate procedural constraints to prevent confirmation bias?

    Without doing double blinds, 70% seems like a horribly bad result, and no more than what would be expected from confirmation bias.

    That's just nonsense. You can't tell whether confirmation bias is present by the level of success! That's not how stats work. In some cases, confirmation bias could easily produce a 95% or even 100% success rate. In other cases, it would be barely better than chance. You can only tell confirmation bias by looking at procedure and data analysis techniques.

    And in any case, I'm surprised at the statistical ignorance shown by many posts in this thread. 70% success where 50% is chance may or may not be a significant finding -- if you do it with 10 questions (or coin flips or whatever), it's probably not significant. But if you ask a million questions or flip a coin a MILLION times and see 70% heads or whatever, it's pretty strong evidence of a pattern. (Would you place a 1:1 wager and gamble against heads on a coin after a million flips like that?)

    But again, whether the result shows strong statistical significance from data analysis is a different question from whether confirmation bias could be present in the procedure.

  5. I don't want to die. by Anonymous Coward · · Score: 5, Insightful

    This bullshit about how we all have to grow old and die has got to fucking stop. Humanity need to quit dragging its feet and fucking cure aging. Our species has waited long enough. It is time for the dying to stop.

    For god's sake, get on it!