This is the EXACT post I was asking for, deep and thoughtful, thank you !!
"John H" <john at faraway> skrev i melding news:3b22f48b_2 at news01.one.net.au...
> Speculative ideas can be fun, I generate a dozen or so each week. I also
> know that these can be damn annoying for other people. If you have an
> interesting speculation consider the following:
>> 1. Someone has thought of it before, you just haven't read enough.
> 2. Someone has thought of it before, and knows why it is a stupid idea.
> 3. No-one has thought of it before, consider seeing a psychiatrist.
How about dividing no.3 in a and b, like:
a)The thought is theoretically possible, but it requiers much time and
b)The thought is NOT possible even theoretically, and it's a waste of time
Of course I know 1 and 2, but that's why I mused and asked if anybody
knew of any kind of research that would illuminate this speculation.
Your posting proved that.
> If you genuinely believe you have a decent idea, do some work on it, read
> the relevant research, bring this into your argument(not formal
> just enough to indicate that the data does exist) so that people can see
> have done some research and are prepared to put in an effort to
> your own ideas. If you're not prepared to do this you can't expect others
> work hard on your speculations.
But I didn't expect to get so much ridicule............
> I follow this heuristic with my ideas: 90% are bad, 9% are good, 1% merit
> deep investigation. Ideas are easy, proving the same is another matter
> I learnt the hard way, when I first came to bionet.neuroscience, now
> returned after an extended absence, there were numerous quality neuros
> to help me along (F Lefever, D Sternberg, M Jones, N Medford + a few
> Unfortunately the kook show factor overwhelmed bionet.neuroscience and so
> many of these fine minds went away. A great loss to me because I have
> access to such minds and relied heavily on this forum to sharpen and
> my neuro thinking. If you're amateur like myself you're going to need
> nothing is easy here. Get used to copping flak, its inevitable and you
> quicker that way. The final goal is to find your mistakes before anyone
> does, but that doesn't happen as often as I would like. We need each other
> for that.
I'm an amatuer like yourself, but with an education in electronics - I got
away by the possibilities of extension with the brain-machine interface that
is interested in commercializing.
> As to visual training, from vague memories:
>> Some fascinating experiments were conducted in which blind individuals
> fitted with a plate on their back. This plate contained hundreds of tiny
> knobs that touched the skin to create a specific pattern representing a
> letter or whatever. Through this mechanism the individuals could be
> to 'see' the pattern.
I've read the same thing that you wrote here.
> There are currently some very experimental trials in visual replacement.
> case I vaguely remember is that of an individual fitted with a tiny video
> camera in the eyesocket. This was attached to a series of electrodes
> implanted into the rear of the skull for primary visual stimulation. The
> news report on this said the scientists claimed this will enable a person
> see eventually. My problems with this are:
I saw it on a program, were they simulated how the individual would 'see'.
It was a 4x4 vision and the 'pixels' could have either black or white
They said they were going to improve on it, but if you just stick the
electrodes into the brain; you're limiting your possibilities.
I don't want limitations.
>> The primary visual cortex is but one of multiple processing modalities.
> Upstream of this are the 'higher' visual areas, the dorsal and ventral
> streams which deal with specific aspects of vision (place and
> I think), and then there's the frontal eye fields, and the prefrontal
> also has a role in visual memory and attention(read some beautiful studies
> by Goldman Rakic on that!). Full vision is not recreating a picture in the
> mind. I don't know what it is, but it is not that. Simultaneous
> of all the relevant neural regions is my best guess but that says nothing
> and is a given ... .
I go with that, because it makes sense.
We have 3D-vision, not 2D vision; never doubted that.
Just wondered if the VC could be re-trained, or possibly extended with
stem-cells reprogrammed by vectors to serve as neuron-cells.
Thus the reference to C.J.A.Ring and E.D.Blair
>> Downstream (relative to retina) the optic nerves send projections to
> superior collicus (for saccade control among other things I think), the
> lateral geniculate nucleus, and with respect to the latter retains retinal
> geometry, as does happen in the primary visual cortex.
>> It is interesting that I have not seen any followups to the above
> experiment, my guess they are having all sorts of problems. With this
> external stimulation of the visual cortex how can visual attention be
> oriented? What about colour? Does the stimulation of the visual cortex
> create the broadest possible geometric patterns(hence the early promise)
> never allow for fine discrimination? Will the individuals ever be able to
> truly locate visual objects in geometric space?
I think they hit the wall, because they were limiting themselves.
A video-camera gives only a 2D-image while the eyes is more complicated.
They have to develope a video-camera that gives 3D-information; which is
not impossible, but difficult at best.
I don't claim that I have the solution, but one solution would be to
a video-camera are working like the eye.
Not linear as video-cameras today, but 'rounded' if you know what I mean.
>> Japanese scientists have overcome the above problems by inserting tiny
> sensitive devices into the retina and these then fire up retinal
> assemblies. Now that is a real possible solution but again we are a very
> long way from achieving the degrees of resolution that individual retinal
> cells achieve (down to 7 photons). My guess is that the greatest promise
> this technology will be for those born blind at birth, but then one would
> have little time to have the device fitted because the visual cortex will
> 'shut down' and stay that way even after intensive stimulation (Hubel's
> 'monocular' cats).
The solution would be to reprogram these cells by inserting vectors made
specifically for the VC.
>> I cannot reference this but remember reading of a 15 year old blind boy
> could ride his push bike around the block via echolocation. Apparently it
> does happen with some blind people though rarely to that level of
> proficiency. My spin on this is:
>> The auditory cortex exists primarily in two layers, its processing is
> at identifying sound source and frequency. However, in blind individuals
> there is a gradual recruitment of some visual processing areas for sound
> processing. This visual cortex is ideally designed for geometric and
> properties of objects. The stimulation of the visual cortex via sound
> probably leads to downstream activation of the dorsal or ventral stream,
> thereby allowing for much greater discrimination in sound processing.
>> Consider synaethesia (spelling!), where sensory modalities overlap - eg.
> sounds generate colours. It is believed that babies experience this, and
> studies on the Russian mnemonic(Luria's patient) indicate this as he
> to be one of the VERY FEW people who accurately recalls very early
> experiences(at circa age 5 we forget most of our childhood). At this time
> the brain has not delinaeated the various sensory modalities, that takes
> time. In some individuals this process never quite finalises.
>> Consider 'gaze tinnitus' where if an individual stares in a certain
> direction then tinnitus ensues. This may relate to ocular nerve
> to auditory cortex (there is research indicating that tinnitus arises in
> auditory cortex, not the cochlea itself). The brain is not as neat and
> as all those diagrams suggest ... .
>> Consider the recent fascinating work of Ed Taub, wherein by forcing
> individuals to use their paralzyed limb some recovery of function could be
>> Clearly then sensory modalities are far more flexible then we are
> to think. However, I cannot see the value in directly acting on the brain
> extend visual awareness for different frequencies. We have technology that
> can do that and do it much more powerfully and safely than mucking around
> with brains. Furthermore, such a technology would overload the brain, even
> if we could generate the expanded wavelength receptivity it would probably
> be at the cost of other modalities. There's no free lunch in the CNS and
> don't give me that 'but we only use 10% of our brain so why not ... . A
> myth, if you keep loading up the brain with too many tasks you'll probably
> end up with excitatory amino acid induced apoptosis and necrosis. Ask any
> poor chronic epileptic ... . Particularly re hippocampus (highest
> concentration of NMDA receptors) and the PFC.
>> In complete contradiction to my first subject I have not researched this.
> Off the top, speculative. Go for your life everyone!
>>> John H.
Great thoughts, but I have never thought that the brain limits itself (10%).
That doesn't make sense.
Who in his/her right mind would limit his/her capabilities ?
Anyway -I have to ask you if you know this for a fact - is it in the VC
the 3D-visualation/modelling exisits ?
Thanks for great post, BTW