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New Imaging Technique Helps Explain Unconsciousness

Posted by Soulskill on from the beware-the-unexpected-nap-attack dept.

smitty777 writes "A new imaging technique called fEITER (for functional Electrical Impedance Tomography by Evoked Response) attempts to explain the process of slipping into unconsciousness. The fEITER is a portable device that creates 3D imagery based on evoked potentials measured hundreds of times a second. The interesting finding from these studies is that unconsciousness appears to result from a buildup of inhibitor neurons. From the article: 'Our findings suggest that unconsciousness may be the increase of inhibitory assemblies across the brain's cortex. These findings lend support to Greenfield's hypothesis of neural assemblies forming consciousness.'"

11 of 78 comments (clear)

  1. The device is as newsworthy as the results by bughunter · · Score: 5, Insightful

    FTFA:

    The machine itself is a portable, light-weight monitor, which can fit on a small trolley. It has 32 electrodes that are fitted around the patient’s head. A small, high-frequency electric current (too small to be felt or have any effect) is passed between two of the electrodes, and the voltages between other pairs of electrodes are measured in a process that takes less than one-thousandth of a second.

    While we're still a long way away from a practical direct neural interface, this certainly looks like a step in the right direction. They've demonstrated that the measurements are possible, and at a sample rate that is useful. Certainly there's room for improvement in sensitivity, sample rate, and resolution as well as in miniaturization.

    When they can reduce this from a trolleycart -sized instrument to something one can support on one's head, then we'll see some more practical and less academic applications. (Yes, like porn. And games. And real virtual reality control of UAVs and waldoes.) Keep in mind that in the 80's, realtime Heads-Up Displays were this large and cumbersome... now look at them.

    It really is illuminating to see how little we know about the nature of consciousness and thought, and how far away we still are from technologically-aided introspection.

    --
    I can see the fnords!
    1. Re:The device is as newsworthy as the results by yarnosh · · Score: 4, Informative

      When they can reduce this from a trolleycart -sized instrument to something one can support on one's head, then we'll see some more practical and less academic applications. (Yes, like porn. And games. And real virtual reality control of UAVs and waldoes.) Keep in mind that in the 80's, realtime Heads-Up Displays were this large and cumbersome... now look at them.

      Are you, perhaps, confusing reading neural activity with sending specific information into the brain? As far as I can tell, the technology in the article is only for reading neurons activity, not altering them. And even at that, there's no indication that you can extract any real information out of the readings (thoughts, intentions, etc). It is simply an image of activity. I think you're reading WAYYY more into this technology than is there.

    2. Re:The device is as newsworthy as the results by Dachannien · · Score: 2

      And even at that, there's no indication that you can extract any real information out of the readings (thoughts, intentions, etc).

      Classifier technology is already advanced enough that making this jump shouldn't be too difficult. The real limitations are (a) the amount of data to be processed and (b) the resolution of the sensors.

  2. Explaining Unconsciousness? by sgage · · Score: 3, Insightful

    This is absurd. For a start, we don't have clue one about how to explain consciousness. Secondly, recording physical correlates to unconsciousness is not an explanation. Like so much of this stuff, it is description masquerading as explanation. Not bad as a start, perhaps, but don't call it "explanation".

    1. Re:Explaining Unconsciousness? by smitty777 · · Score: 2

      You're right, we don't have a clue how consciousness works. But this article is about the process of becoming unconscious, which is vastly different. It is significant that we can now associate precise physical components with the act of becoming unconscious. Since we are the ones putting the person under, we know that it's at least a partial explanation, which is something we didn't know before.

      --
      "Before God we are all equally wise - and equally foolish"
      Albert Einstein
  3. You're implicitly assuming dualism by Fred+Ferrigno · · Score: 3, Informative

    You're upset that the researchers don't also assume that consciousness is some other kind of thing beyond material investigation. The researchers have no need for that assumption unless and until the evidence leads them there.

  4. Re:Yes, the Cat Has My Tongue by SydShamino · · Score: 3, Insightful

    Well if neural inhibitors (which interfere with the processing of certain parts of our neural network) cause us to lose consciousness, then one could hypothesize that those parts of our neural network must play a role in consciousness. And that makes us at least a little closer to understanding it.

    --
    It doesn't hurt to be nice.
  5. Re:Yes, the Cat Has My Tongue by TrekkieGod · · Score: 3, Insightful

    I mean, a blow to the head will also cause us to lose consciousness. But it won't help us understand what makes us conscious.

    Actually, it does. It tells us that the organ responsible for consciousness resides in the head. Similarly, we've discovered a lot about what different regions of the brain are responsible for by looking at people who received brain damage to different areas and looking at what they were now unable to do as a result. You know the brain is responsible for consciousness, this can help narrow down what brain activity is involved by looking at what activity is inhibited when you're unconscious.

    --

    Warning: Opinions known to be heavily biased.

  6. Re:Yes, the Cat Has My Tongue by ceoyoyo · · Score: 2

    Well, to start with, the actual mechanism by which general anaesthetic causes unconsciousness is unknown. It's interesting to know how something we use so much actually works. And it might be interesting to know whether it works by the same mechanism that falling asleep naturally does.

  7. Re:Yes, the Cat Has My Tongue by sjames · · Score: 2

    For starters, it might allow us to develop safer anesthetics and a more effective measure of the depth of anesthesia during surgery so that patients can be given just enough without risk of awareness during the procedure.

    The current devices for that are known to have a significant margin for error.

  8. Re:Defensive Implant by TheLink · · Score: 2

    Oh yeah, I'm sure the main problem with an IED is overloading sensory brain parts, and that soldiers would be quite happy to not be unconscious after getting hit with an IED and losing a limb or three. They'd rather be able to soberly savour the reality of their situation and the consequences. So most would gladly give an arm and leg for such an implant.

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