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Human consciousness, awareness or whatever?

  1. Dec 15, 2012 #1
    Its a tough question to ask and I am looking for a scientific answer.
    How can we talk in our mind? I mean when we think about something it feels as if we are talking in our head. They are multiple arguments going on in our head and you can listen to it. What is it?

    This question arose when I was thinking how differently computers and humans process inputs?
    Computers just look at the input and give out the output accordingly(the way they have been programmed)
    I supposed that humans behaved the same way. There is a certain stimulus and we behave accordingly.
    But we "understand" what is happening while a computer does not. What is this understanding?

    I hope someone gets and gives me some answer. I don't even know if my question makes sense!
  2. jcsd
  3. Dec 15, 2012 #2
    You're asking what's probably the second biggest question in neuroscience, and no one has definitively answered it. The activity of verbal mental modeling, thinking, is extremely complex and many different parts of the brain contribute to the process. Two exceptionally important areas are Broca's Area and Wernicke's area, without which we can't form language.

    And your question is closely tied to the biggest one in neuroscience, "How are we aware?" What's the mechanism by which we are conscious of our thinking? How does consciousness arise from the activity of neurons?

    At this early stage there are only many hypotheses and speculations.
  4. Dec 15, 2012 #3


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    Do some initial research on Wernicke's and Broca's areas for some insights on speech generation. Auditory hallucinations are interesting in this regard (hearing the voices by not realizing they come from you).

    As for consciousness in general, still a big open subject.
  5. Dec 15, 2012 #4


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    I think the OP is referring to how we talk to ourselves without speaking out loud, not auditory hallucinations.

    Unless he is hearing many voices arguing at once... In which case, I suggest that he see a psychiatrist as soon as possible.
  6. Dec 16, 2012 #5


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    Yeah, I was just pointing out what can happen when the system fails. A specific kind of auditory hallucination where you're talking to yourself and don't know it (perhaps the feedback connection from Brcas area is broken.. So you hear stuff being generated from Broca's area, but don't get the sensation of generating it yourself.)

    Anyway, I recall that Broca's area is active during schizophrenic auditory hallucinations. It's also associated with speech generation in general brain function.
  7. Dec 16, 2012 #6


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  8. Dec 16, 2012 #7
    Broca's area and Wernicke's area could quite possibly have nothing to do with the OP question (talk in our mind), and of course conciousness. I tend to look at it as Broca's and Wernicke's as mechanical, moving parts...in compared to a state of conciousness and "talkin in the head" as talking in the head could be done with someone that has no knowledge of language, this person can still talk in his/her head.

    It's such a fabulous question, and I hope we answer this holy grail of neuroscience in my life time.

    You never know... It could be more of a question of Physics :)
    Last edited: Dec 16, 2012
  9. Dec 17, 2012 #8
    nukeman is correct.
    Lateralization of function has loss considerable ground viewed from recent research.
    Which is inadequate to answer the question posed here.
    The question is more a question of physics.

    A wave theory - the one I have in mind has a median for propagation (mechanical vibration) - explains all of the cognitive human existence and experiences.
    Recent research from Norway offers a 'new way to organize' human existence.
    They label this 'sense of location' - of which there are at least five such senses and asserted are as many as ten such senses.

    This explains all forms of Synesthesia without lateralization of function.

    A good start to make sense of a good question.

    The 'talk' (information) of any vibration your senses are able to resolve, send and imprint upon your brain doesn't need the extra 'meaning' assigned (associated) from the sounds of the future language you will acquired after birth.
  10. Dec 17, 2012 #9
    Nobody has made progress on this question since George Berkeley wrote his 1710 piece "A TREATISE CONCERNING THE PRINCIPLES OF HUMAN KNOWLEDGE". You can read the whole thing in one evening, spend a lifetime catching up to his insights, no one has made it passed him yet. He wrote this in his early 20's and it remains one of the most amazing works on this planet.

    The whole thing can be read on-line here.
  11. Dec 17, 2012 #10
    No. Without language there is no talking. You can still process information visually, which would constitute a form of thinking, but it wouldn't be proper to call this "talking".

    You ought to read "My Stroke of Insight" by Jill Taylor. She was a neuroscientist who had her left hemisphere pretty much disabled when an AVM burst. First she developed receptive and expressive aphasia and within a couple days all internal talking went silent. It took her years to recover and her first hand account of what the experience was like is astonishing.

    "The most notable difference between my pre- and post-stroke cognitive experience was the dramatic silence that had taken up residency inside my head. It wasn't that I could not think anymore, I just didn't think in the same way. Communication with the external world was out. Language with linear processing was out. But thinking in pictures was in. Gathering glimpses of information, moment by moment, and then taking time to ponder the experience, was in."

    pp 75-76
  12. Dec 18, 2012 #11


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    Broca's area certainly has something to do with internal dialogue[1][2]. Whether you look at them as internal moving parts is not particularly relevant. Insight can still be gained by studying the nuclei involved in internal speech. In fact, mechanisms/functionality are probably all we can talk about inevitably. Phenomenology will always be subject to... well, subjectivity.

    Consciousness, as I indicated in post #3, is a (separate) huge subject. There are several interesting frameworks being developed. Off the top of my head, I know of three that have been published[3][4][5].

    The problem with discussions on consciousness is it's such a vast subject with several key factors, but each individual tends to emphasize a different factor as being consciousness. I personally think The Hard Problem is the key aspect of consciousness and I also don't think it will really ever be solved. We could imagine a hard problem for gravity and electromagnetism. We don't know why or how are charge exists. Once we get to fundamental laws, we just accept them as the are. There's not much more we can do. I imagine it will be the same with consciousness. We'll learn more about it and the mechanisms involved, but we'll never actually solve the hard problem.


    [1] Hinke RM, Hu X, Stillman AE, Kim SG, Merkle H, Salmi R, Ugurbil K. (1993). Functional magnetic resonance imaging of Broca's area during internal speech. Neuroreport. 1993 Jun;4(6):675-8.

    [2] Morin, A. (2005). Possible Links Between Self-Awareness and Inner Speech Theoretical background, underlying mechanisms, and empirical evidence. Journal of Consciousness Studies, Volume 12, Numbers 4-5, pp. 115-134(20).

    [3] Friston, K. (2010). The free-energy principle: a unified brain theory? Nature Reviews Neuroscience 11, 127-138.

    [4] Crick, F. and Koch C. (1998). Consciousness and Neuroscience. Cerebral Cortex, 8:97-107.

    [5] Varela F, Lachaux JP, Rodriguez E, Martinerie J. (2001). The brainweb: phase synchronization and large-scale integration. Nat Rev Neurosci. 2001 Apr;2(4):229-39.
  13. Dec 18, 2012 #12


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    I'm not sure where you saw an argument for strict lateralization. There are certainly lateralization tendencies in the brain, but that's irrelevant to my post that nukem responded to. Not really sure what the point is in the rest of your post.
  14. Dec 18, 2012 #13
    Do some initial research on Wernicke's and Broca's areas for some insights on speech generation.

    This is where I saw the argument for strict lateralization.
    With over 60 types of synesthesia and counting lateralization is becoming irrelevant.
  15. Dec 18, 2012 #14


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    Why don't you explicitly tell me what you think is wrong with the sentence and avoid using jargon? Lateralization can mean different things (left/right or across individuals). Anyway, you shouldn't need jargon if you have a clear point.
  16. Dec 19, 2012 #15
    Wernicke's and Broca's areas are areas called lateralizations of functions.
    You recommend these areas for 'some insights on speech generation' to be found there.
    What are the insights on speech generation to be found there?
    Your point is: there are insights on speech generation to be found by doing initial research on
    Wernicke's and Broca's areas.
    My point is: state the insights on speech generation you found doing initial research on Wernicke's and Broca' areas.
    Why are these specific regions associated speech generation?
    What happens to these areas when these functions are shifted to other areas of the brain?

    All forms of synesthesia are shifted areas of function.
    What that tells you is whatever consciousness or awareness or whatever is...
    that can be shifted as well.

    Let's hear about your insights.
  17. Dec 19, 2012 #16


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    You're not using lateralization right (perhaps I am misunderstanding)... the areas themselves are not called lateralizations. "Lateralization of function" is a concept. The concept that functions are lateralized across left-right brain. I made no such assertion that functions must be lateralized. Wernicke's and Broca's areas aren't lateral from each other.

    All of cortex is remarkably similar to each other in terms of structural organization, certainly. So each part can theoretically do what the other part can in terms of processing. However, inputs and outputs allow particular regions of cortex to become "wired" one way or another, so in terms of functional organization, there's certainly validity to associating speech generation with Broca's area.

    Obviously, there's exceptions.. and damage to Broca's area at an early enough age will lead to the functionality being developed elsewhere. However, if you present a lesion to Broca's area after the region has developed for functionality (i.e. in a neurotypical adult) you will certainly tamper with their ability to generate speech!

    The insights that can be gained is to look at the inputs and outputs to Broca's area and consider them as what speech generation is made up of. This, of course, is a difficult task, but not impossible. Broca's area is probably made up several nuclei itself, each of which can have more specific processing contributions (in a neurotypical adult, of course... do I really have to say that every time?)

    I am between homes, currently. My internet connection is slow and I don't have access to the literature here, so I can't be more descriptive.

    For now, perhaps this can give you some deeper insight. It describes the Wernicke-Geschwind model, in particular (which is useful, but like any model, has deficiencies). Thankfully, the link provides other models to address some of these deficiencies:

    Why should consciousness (or even language generation) just be in one spot in the brain?

    Gaining insight from a section of the processing stream and associating functionality with a region of the brain is not the same as saying that these functions exist only in this part of the brain.

    Can you back this up with some literature? I remember hearing that the neurobiology of synesthesia was still an open question and that one hypothesis was that there was cross-wiring occurring between different sensory processing regions. There was another hypothesis that I don't recall from the talk. Perhaps you are more informed than I.
    Last edited: Dec 19, 2012
  18. Dec 19, 2012 #17


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    "Neuroscience for Kids" maintained by Washington University (don't let the title fool you) says:

  19. Dec 19, 2012 #18

    This came out frequently in the links posted in the huge synesthesia thread. There doesn't seem to be any evidence for physical "cross-wiring". Testing shows the experiencer has to cognitively apprehend the stimulus before the second sense kicks in.
  20. Dec 19, 2012 #19


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    What's the evidence of concurrents? I see the assertion, but wikipedia doesn't divulge the method.

    Scholarpedia is generally more thoroughly referenced, and you might interpret some of its references as "evidence":

    but Scholarpedia also tends to be idiosyncratic sometimes since the original authors write the Scholarpedia articles (this one is written by Ramachandran who references his own work, so possible conflict of interests).

    Anyway, Ramachandran distinguishes between (at least, didn't read it all) two different synesthetes: "lower synesthetes" and "higher synesthetes". You can probably guess by the names which name refers to which of the theories each of us has introduced in this thread.

    Anyway, we're getting off topic.
  21. Dec 19, 2012 #20
    This article goes into more depth:

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