Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Medical MRI Mind Reading claim (newspaper)

  1. Sep 22, 2011 #1
    http://www.smh.com.au/technology/sc...structs-videos-from-brain-20110923-1ko5s.html

    bg-pair2-420x0.jpg

    ::I can't locate the primary source::

    Didn't want to put this in skepticism or another sub section.. too interesting. Move if wrong thanks.
     
  2. jcsd
  3. Sep 22, 2011 #2
    Here's what it sounded like to me: the scanner picks up some sort of information from the brain which is then fed to a computer. The computer is then given a multiple choice of video clips to match the information to. It picks one and superimposes that clip onto the information somehow to create the image we were shown. Not as interesting as it seems at first.
     
  4. Sep 22, 2011 #3
    Why are the images all fuzzy :s

    Why can't they just pull up the actual image that they're guessing why do they have to "recreate" it?

    Thanks.
     
  5. Sep 23, 2011 #4

    Ygggdrasil

    User Avatar
    Science Advisor

    Here's a link to the primary source, for those interested in reading the paper: http://www.cell.com/current-biology/fulltext/S0960-9822(11)00937-7?switch=standard

    Abstract:
    Quantitative modeling of human brain activity can provide crucial insights about cortical representations [1,2] and can form the basis for brain decoding devices [3,4,5]. Recent functional magnetic resonance imaging (fMRI) studies have modeled brain activity elicited by static visual patterns and have reconstructed these patterns from brain activity [6,7,8]. However, blood oxygen level-dependent (BOLD) signals measured via fMRI are very slow [9], so it has been difficult to model brain activity elicited by dynamic stimuli such as natural movies. Here we present a new motion-energy [10,11] encoding model that largely overcomes this limitation. The model describes fast visual information and slow hemodynamics by separate components. We recorded BOLD signals in occipitotemporal visual cortex of human subjects who watched natural movies and fit the model separately to individual voxels. Visualization of the fit models reveals how early visual areas represent the information in movies. To demonstrate the power of our approach, we also constructed a Bayesian decoder [8] by combining estimated encoding models with a sampled natural movie prior. The decoder provides remarkable reconstructions of the viewed movies. These results demonstrate that dynamic brain activity measured under naturalistic conditions can be decoded using current fMRI technology.
     
  6. Sep 23, 2011 #5

    Pythagorean

    User Avatar
    Gold Member

    Not quite, they are actually predicting based only on neural activity. But they are associating (through Bayesian method) that neural activity with elementary motions and then reconstructing the movie they're actually watching with the elements of motion.

    They do this by training the voxel definition(s?) on each individual subject.

    The neurons they're recording are encoding motion, not a static image, so rather than having a bank of colors (that comes standard with every computer nowdays), they need a bank of motions (which does not come standard with computers). They gathered that bank of motions from youtube (and they were not the same clips the subjects actually saw, they are just a bank of elementary motions).

     
    Last edited: Sep 23, 2011
  7. Sep 24, 2011 #6
    Yes, I see from your explanation I misunderstood the "bank" to be much simpler than it actually is, and therefore misunderstood what the result demonstrated. It is more interesting than I thought. Thanks for clarifying.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: MRI Mind Reading claim (newspaper)
  1. The Mind (Replies: 2)

  2. Need MRI (Replies: 3)

  3. MRI question (Replies: 10)

Loading...