Hi Craig Weinberg 

Sorry, everybody, I was snookered into believing that they had really 
accomplished the impossible.
The killer argument against that is that the brain has no sync signals to 
generate
the raster lines.


[Roger Clough], [rclo...@verizon.net]
1/6/2013 
"Forever is a long time, especially near the end." - Woody Allen
----- Receiving the following content ----- 
From: Craig Weinberg 
Receiver: everything-list 
Time: 2013-01-05, 11:37:17
Subject: Re: Subjective states can be somehow extracted from brains via 
acomputer




On Saturday, January 5, 2013 10:43:32 AM UTC-5, rclough wrote:

Subjective states can somehow be extracted from brains via a computer. 


No, they can't.
 


The ingenius folks who were miraculously able to extract an image from the 
brain 
that we saw recently 


http://gizmodo.com/5843117/scientists-reconstruct-video-clips-from-brain-activity
 

somehow did it entirely through computation. How was that possible? 


By passing off a weak Bayesian regression analysis as a terrific consciousness 
breakthrough. Look again at the image comparisons. There is nothing being 
reconstructed, there is only the visual noise of many superimposed shapes which 
least dis-resembles the test image. It's not even stage magic, it's just a 
search engine.
 


There are at least two imaginable theories, neither of which I can explain step 
by step: 



What they did was take lots of images and correlate patterns in the V1 region 
of the brain with those that corresponded V1 patterns in others who had viewed 
the known images. It's statistical guesswork and it is complete crap.

"The computer analyzed 18 million seconds of random YouTube video, building a 
database of potential brain activity for each clip. From all these videos, the 
software picked the one hundred clips that caused a brain activity more similar 
to the ones the subject watched, combining them into one final movie"

Crick and Koch found in their 1995 study that


"The conscious visual representation is likely to be distributed over more than 
one area of the cerebral cortex and possibly over certain subcortical 
structures as well. We have argued (Crick and Koch, 1995a) that in primates, 
contrary to most received opinion, it is not located in cortical area V1 (also 
called the striate cortex or area 17). Some of the experimental evidence in 
support of this hypothesis is outlined below. This is not to say that what goes 
on in V1 is not important, and indeed may be crucial, for most forms of vivid 
visual awareness. What we suggest is that the neural activity there is not 
directly correlated with what is seen."


http://www.klab.caltech.edu/~koch/crick-koch-cc-97.html

What was found in their study, through experiments which isolated the effects 
in the brain which are related to looking (i.e. directing your eyeballs to move 
around) from those related to seeing (the appearance of images, colors, etc) is 
that the activity in the V1 is exactly the same whether the person sees 
anything or not. 

What the visual reconstruction is based on is the activity in the 
occipitotemporal visual cortex. (downstream of V1 
http://www.sciencedirect.com/science/article/pii/S0079612305490196)


"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." 
https://sites.google.com/site/gallantlabucb/publications/nishimoto-et-al-2011


So what they did is analogous to tracing the rectangle pattern that your eyes 
make when generally tracing the contrast boundary of a door-like image and then 
comparing that pattern to patterns made by other people's eyes tracing the 
known images of doors. It's really no closer to any direct access to your 
interior state than any data-mining advertiser gets by chasing after your web 
history to determine that you might buy prostate vitamins if you are watching a 
Rolling Stones YouTube.



a) Computers are themselves conscious (which can neither be proven nor 
disproven) 
    and are therefore capable of perception. 


Nothing can be considered conscious unless it has the capacity to act in its 
own interest. Computers, by virtue of their perpetual servitude to human will, 
are not conscious.
 


    or 

2) The flesh of the brain is simultaneously objective and subjective. 
    Thus an ordinary (by which I mean not conscious) computer can work on it 
    objectively yet produce a subjective image by some manipulation of the 
flesh 
    of the brain. One perhaps might call this "milking" of the brain.   


The flesh of the brain is indeed simultaneously objective and subjective (as 
are all living cells and perhaps all molecules and atoms), but the noise 
comparisons being done in this experiment aren't milking anything but the hype 
machine of pop-sci neuro-fluff. It is cool that they are able to refine the 
matching of patterns in the brain to patterns which can be identify 
computationally, but without the expectation of a visual image corresponding to 
these patterns in the first place, it is meaningless as far as understanding 
consciousness. What it does do though is provide a new hunger for invasive 
neurological technologies to analyze the behavior of your brain and draw 
statistical conclusions from...something which promises nothing less than 
utopian/dystopian level developments. 

Craig
 


[Roger Clough], [rcl...@verizon.net] 
1/5/2013   
"Forever is a long time, especially near the end." - Woody Allen 

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