Hi Telmo Menezes
Presumably the brain works with analog, not digital, signals.
But the redisplay of the brain image requires a digital image signal.
How can that happen ?
If the recponstructed brain image has no sync signal,
how couold it display in a digital device ?
[Roger Clough], [rclo...@verizon.net]
1/8/2013
Forever is a long time, especially near the end. - Woody Allen
- Receiving the following content -
From: Telmo Menezes
Receiver: everything-list
Time: 2013-01-07, 17:34:21
Subject: Re: Re: Re: Re: Subjective states can be somehow extracted
frombrainsviaacomputer
Hi Roger,
Imagine a very simple brain that can recognise two things: a cat and a mouse.
Furthermore, it can recognise if an object is still or in motion. So a possible
perceptual state could be cat(still) + mouse(in motion). The visual cortex of
this brain is complex enough to process the input of a normal human eye and
convert it into these representations. It has a very simple memory that can
store states and temporal precedence between states. For example:
mouse(still) - cat(in motion) + mouse(still) - cat(still) + mouse(in motion)
- cat(still)
Through an MRI we read the activation level of neurons that somehow encode this
sequence of states. An incredible amount of information is lost BUT it is
possible to represent a visual scene that approximates the meanings of those
states. In a regular VGA screen with a synch signal I show you an animation of
a mouse standing still, a cat appearing and so on. Of course the cat may be
quite different from what the brain actually perceived. But it is also
recognised as a cat by the brain, it produces an equivalent state so it's good
enough.
Now imagine the brain can encode more properties about objects. Is is big or
small? Furry? Dark or light?
Now imagine the brain can encode more information about precedence. Was it a
long time ago? Just now? Aeons ago?
And so on and so on until you get to a point where the reconstructed video is
almost like what the brain saw. No synch signal.
On Mon, Jan 7, 2013 at 5:22 PM, Roger Clough wrote:
Hi Telmo Menezes
Yes, but the display they show wouldn't work if there were no
sync signal embedded in it. There's nothing in the brain to provide that,
so they must have.
[Roger Clough], [rclo...@verizon.net]
1/7/2013
Forever is a long time, especially near the end. - Woody Allen
- Receiving the following content -
From: Telmo Menezes
Receiver: everything-list
Time: 2013-01-07, 09:33:30
Subject: Re: Re: Re: Subjective states can be somehow extracted from
brainsviaacomputer
Hi Roger,
On Mon, Jan 7, 2013 at 1:28 PM, Roger Clough wrote:
Hi Telmo Menezes
Well then, we have at least one vote supporting the results.
Scientific results are not supported or refuted by votes.
I remain sceptical because of the line sync issue.
The brain doesn't provide a raster line sync signal.
The synch signal is a requirement of a very specific technology to display
video. Analog film does not have a synch signal. It still does sampling.
Sampling is always necessary if you use a finite machine to record some visual
representation of the world. If one believes the brain stores our memories (I
know you don't) you have to believe that it samples perceptual information
somehow. It will probably not be as neat and simple as a sync signal.
A trivial but important point: every movie is a representation of reality, not
reality itself. It's just a set of symbols that represent the world as seen
from a specific point of view in the form of a matrix of discrete light
intensity levels. So the mapping from symbols to visual representations is
always present, no matter what technology you use. Again, the sync signal is
just a detail of the implementation of one such technologies.
The way the brain encodes images is surely very complex and convoluted. Why
not? There wasn't ever any adaptive pressure for the encoding to be easily
translated from the outputs of an MRI machine. If we require all contact
between males and females to be done through MRI machines and wait a couple
million years maybe that will change. We might even get a sync signal, who
knows?
Either you believe that the brain encodes images somehow, or you believe that
the brain is an absurd mechanism. Why are the optic nerves connected to the
brain? Why does the visual cortex fire in specific ways when shown specific
images? Why can we tell from brain activity if someone is nervous, asleep,
solving a math problem of painting?
[Roger Clough], [rclo...@verizon.net]
1/7/2013
Forever is a long time, especially near the end. - Woody Allen
- Receiving the following content -
From: Telmo Menezes
Receiver: everything-list
Time: 2013-01-07, 06:19:33
Subject: Re: Re: Subjective states can be somehow extracted from brains
viaacomputer
On Sun, Jan 6, 2013 at 8:55
