sozobe wrote:I'm going to have to look this stuff up, but here is my off-the-cuff memory of how neural pathways et al work:
There is an actual building process, that results in the "eureka!" lightbulb moment when a new connection is forged. I think that could work in tandem with pathways which are not being used falling into dormancy.
If I understand the idea correctly, it's more a matter of comparative viability among possible pathways than it is about pathways which exist or don't exist.
sozobe wrote:(by the way, dreams are thought to help with this pathway building, but that's another thread)
That's interesting. I wonder if the random and less focused aspect of dreams allows the neurons to fire in a more balanced fashion, thus opening otherwise less uses pathways.
rosborne, nope, that's not quite what I was getting at. (Again, no claims as to scientific accuracy yet, just what I remember from a few years ago.)
I think that what you bring up -- neural pathways being there, and being used or not -- and what I am speaking of are not mutually exclusive, at all. But what I am getting at is more that in addition to that, completely new pathways are built. It's not JUST that all possible pathways are there and are used or not. Actions and various learning techniques contribute to the building of a connection, until the connection is made, and a new pathway exists.
I'll go look around a bit now, see what I can come up with.
sozobe wrote:rosborne, nope, that's not quite what I was getting at. (Again, no claims as to scientific accuracy yet, just what I remember from a few years ago.)
I think that what you bring up -- neural pathways being there, and being used or not -- and what I am speaking of are not mutually exclusive, at all. But what I am getting at is more that in addition to that, completely new pathways are built. It's not JUST that all possible pathways are there and are used or not. Actions and various learning techniques contribute to the building of a connection, until the connection is made, and a new pathway exists.
I'll go look around a bit now, see what I can come up with.
Hi Soz, I think we're talking about the same thing here and using different terminology.
For example, when you say "a neural pathway is built", exactly what is that? Is a new neuron grown, or a new dendrite extruded, or it is just that an impulse has moved across at a place never (or rarely) used before.
To me a new neural pathway is built every time an impulse travels it for the first time. But how often an impulse goes that way may have more to do with how we "feel" about it (eureka moments).
sozobe wrote:Neural pathways were on their way, but no connections had been made yet. If I'd stopped at that point, they would have just shriveled again. But I kept going, kept going, the pathways inched (well, of course, some measurement much smaller than an inch) forward, the visual pathway say inching toward the language pathway, and then voila!
I think a better metaphor is: walking through countryside filled full of long grass. Consider the grass to be the space between neural nodes. When you start off walking you leave behind a light trail. If you went back a week later you wouldn't be able to find it again - entropy as stolen it! However, if you use it everyday you might be able to find your previous path, you might not. However, if you use the same path every five minutes, that is your brain is being triggered every five minutes, entropy won't have a chance to act and you'll be able to find the path again. With heavy use the path comes wider and better established. If later, however, a shortcut suddenly appears the old clear path will slowly become grown over with grass and eventually lost and forgotten. In rare cases people do forget their first languages with lack of use.
Iain
I forget the terminology. Useta know it. Will re-acquaint myself.
Found this, to start with:
Quote:The initial establishment of topographic mapping within developing neural circuits is thought to be shaped by innate mechanisms and is primarily independent of experience. Additional refinement within topographic maps leads to precise matching between presynaptic and postsynaptic neurons and is thought to depend on experiential factors during specific sensitive periods in the animal's development. In male zebra finches, axonal projections of the cortical lateral magnocellular nucleus of the anterior neostriatum (lMAN) are critically important for vocal learning. Overall patterns of topographic organization in the majority of these circuits are adult-like throughout the sensitive period for vocal learning and remain stable despite large-scale functional and morphological changes. However, topographic organization within the projection from the core subregion of lMAN (lMAN(core)) to the motor cortical robust nucleus of the archistriatum (RA) is lacking at the onset of song development and emerges during the early stages of vocal learning. To study the effects of song-related experience on patterns of axonal connectivity within different song-control circuits, we disrupted song learning by deafening juvenile zebra finches or exposing them to loud white noise throughout the sensitive period for song learning. Depriving juvenile birds of normal auditory experience delayed the emergence of topographic specificity within the lMAN(core)-->RA circuit relative to age-matched controls, whereas topographic organization within all other projections to and from lMAN was not affected. The projection from lMAN(core) to RA therefore provides an unusual example of experience-dependent modification of large-scale patterns of brain circuitry, in the sense that auditory deprivation influences the development of overall topographic organization in this pathway.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&dopt=abstract&list_uids=11826123
"Yes, but the implication of *why* it's not as easy is the interesting part, don't you think?"
I thought they already knew why - maybe not. In any case, that's a far cry from saying that the ability to learn subsequent languages is destroyed. If any of the neural passages required to learn language were in any way lost, than it wouldn't be possible to fully learn any language after that point, yet adults have studied and become fluent in second and third languages. There is also a book I read that indicates that adults can learn languages like babies do - simply by listening to the languages being spoken, without supplimentary lessons. It just takes a little longer and requires a bit more concentration. If you're interested, the book is called "Who is Fourier?" It's actually sort of a math book about the mathematical nature of phonetics, published by the Transnational College of Lex in Japan, where they use this method of language aquisition to teach their students. I don't know if they have a website or not, I'll have to go look.
Fresco, I think one of the proporties of a pidgin is that it doesn't have a very structured grammar, isn't it?
"There is an actual building process, that results in the "eureka!" lightbulb moment when a new connection is forged."
Actually, I think I remember something exactly like this when I was learning to read. Mind you, I could already speak - I don't remember learning that.
Sozo, are you saying that not only are parts of the brain destroyed, they regenerate? That's an interesting idea. Is there a book or something about that?
Yes, nice metaphor, Iain. I think what we're trying to figure out now is whether the path is there, marked by stones obscured by the grass perhaps, or if it is newly created. I tend towards newly created, but still looking.
Forget the caltech guy's name, just asked my hubby, when he tells me (he knew him better) I'll be able to look him up online and that should take me to the good stuff pretty quick. Wish I remembered anything about the New Yorker article, as that was what helped me understand the technicalities. (Dendrites et al.)
rosborne979 wrote:To me a new neural pathway is built every time an impulse travels it for the first time. But how often an impulse goes that way may have more to do with how we "feel" about it (eureka moments).
I'm working on the wikipedia project which is a very large encyclopedia, or in other words a very large network of information. Before I started working on it there was already a large body of knowledge, and sometimes through various clicks I'm able to establish a logical link between two entries. The entries have existed for sometime, but there needs to be a conscious effort (in this case me) to explore the area (akin to thinking) before a link can be established. And at the point we have Eureka!
Come have a look for yourself:
www.wikipedia.com
Iain
So, are you saying that new connections are formed, or that unused ones never die? I'm confused.
rufio wrote:I thought they already knew why - maybe not. In any case, that's a far cry from saying that the ability to learn subsequent languages is destroyed.
Correct. Nobody ever said this, nor was it implied.
You said the connections were partially destroyed - if that were the case, than a second language would never be as good as a first. But this has been shown otherwise. Clearly, either nothing is destroyed, or anything that was destroyed is retrievable later.
rosborne,
The neurogenesis-related theory I had was initially derived from discussions on IQ. As a child my discovery of the difference between gaining knowledge and improving intelligence was followed by wondering whether intelligence can be improved. One of the things I mentioned to rufio was that even if we decide that the "hardware" doesn't change the ability to learn can still change but way back then that thought led me to question whether the hardware did as well.
In my learning process there were "shortcuts" that once learned made my thinking and learning faster, that challenged the perception that learning could not just add knowledge but also change the capacity to learn. Now the very basic question of whether language changes the way we think can be answered with a resounding yes, but then the even more interesting (to me) question is if the change can be not just systematic but physical and since I was a child I believed that neurogenesis conditional upon stimulation existed. To connect this to language I need to go further back to when I started noticing the effect of learning systems.
As a child I witnessed what the use of techniques to stimulate neural development can do. Whether or not the improvements were physical or not I did witness marked improvements in the young children I saw subjected to them. Use of flashcards were used, both to teach language and to develop spatial cognition. The use of flashcards with random dots on them were interesting. I've seen one year old children recognize a flashcard with 86 or 70 or 99 dots on them at a glance. As a one year old I could do it but a few years later it was a marvel to me that those stupid babies (to a three year old babies are stupid, I.e. not as smart) could. They were trained to recognize spatial patterns that the adults training them could not recognize.
To finally make the connection between my long-winded anecdotal evidence and this topic I noticed as a child that language makes a marked difference. I was living in Japan, and the children were being shown Japanese flashcards as well. When witnessing younger children's training I noticed that the ones who were shown Japanese flashcards seemed to do better with the number dots. I took this to mean that the very "visual" Japanese writing had helped with spatial recognition. And since then this has fascinated me. Other studies have broached the subject of oriental languages and spatial cognition but with the flashcards I saw evidence that, though anecdotal, was striking to the memory.
The development through training was fascinating to watch. Anywho, later on I was made to memorize things daily. Rote became a large learning process in committing large texts to memory and with other learning (e.g. spelling's "Trace, Copy and Recall" methods). I started to look for shortcuts in learning and then began to wonder if what you learn can change your ability to learn.
The obvious answer is YES. The obvious example is that a learned learning system can enable the learning of some things that would otherwise be impossible. Now the last step in the IQ debates I had was the one rufio touched on. About whether "potential" changes.
The arguments were all predicated on the notion that the hardwire doesn't change. But the big difference between the mind and the computer in the analogies made is that in humans, the hardwire is self generating and does change. But does the mind? I long believed that it changes, even when the axiom that the brain cells do not regenerate was accepted. But to this day that axiom is being used as the basis for arguments that are therefore outdated because neurogenesis is a reality.
For example, dlowan tried to kill my buffalo theory based on the previously universal acceptance of the axiom that the brain cells do not regenerate. But this is simply false. Neurogenesis is something I have long believed and is finally getting some play in the scientific community. My theory started with the childhood discovery that intelligence and knowledge are different things, and then to wondering at whether intelligence can be improved, then to realization that learning shortcuts can make improvements, and then to wondering if there can be a physical change, and then to believing there could.
Recently more scientists are believing it, and I hope to see more and more validation of neurogenesis because I think it will be big. I think neurogenesis is a huge key to development and I think neurogenesis is influenced by sensory input.
This site is already mentioned in the
PORTAL of this webside, like a couple of other interesting websites as well :wink:
sozobe wrote:
I'll go look around a bit now, see what I can come up with.
What you are talking about is 1998 and Elizabeth Gould (sp?).
To amend my newly created comment a bit, I don't think that the brain is this big blob of nothing when a baby is born... there is a lot there. I am liking the quote above in terms of explaining baseline and then how experience affects the brain (writing fast sorry will clarify later)
rufio wrote:So, are you saying that new connections are formed, or that unused ones never die? I'm confused.
I think what they were saying is that all (or a vast majority) of the physical, neural (or dendritic) connections are built early in life, and that the more often an impulse travels down a particular path, the easier it is for the next impulse to do the same. The unused ones don't completely shrivel up and die, but they are less likely to recive an impulse when compared to a well used connection.
rufio wrote: Sozo, are you saying that not only are parts of the brain destroyed, they regenerate? That's an interesting idea. Is there a book or something about that?
This has been groundbreaking knowledge in the scientific community for a few years now.
A Google search will lead you to hundreds of studies.
rufio wrote:You said the connections were partially destroyed - if that were the case, than a second language would never be as good as a first. But this has been shown otherwise. Clearly, either nothing is destroyed, or anything that was destroyed is retrievable later.
He was talking anout neural connections he said nothing about not being able to learn other languages.
So they are still there, and not "destroyed" like you said originally.
Craven, I'm sure your childhood intuition can't be wrong. You should write some books on how God came down and told you it was so.
Anyway, I thought this was a free exchange of information. I could search for everything on google, I just don't have the time.
rufio wrote:You said the connections were partially destroyed
Incorrect. I said unused, or less used. I never said destroyed.
rufio wrote: - if that were the case, than a second language would never be as good as a first. But this has been shown otherwise. Clearly, either nothing is destroyed, or anything that was destroyed is retrievable later.
Correct. Nothing is destroyed. Unless of course your car hits a tree or something, then a lot can get destroyed
Best Regards,
