2007-03-29
Storyteller
Telling stories is an important part of our life. It’s a daily activity I wrote about before. See Stories and The emperors new clothes. Now, I just came across some interesting research. Dr. Michael Gazzaniga has located our storyteller in the left hemisphere of the brain. In his research with split-brain patients he discovered that they would tell stories with facts that were known by the left brain and made up a story for the actions done by the right brain.
Dr. Gazzaniga and Dr. LeDoux showed P.S. a picture of a chicken claw in his right eye and a snow-covered house in the left eye. P.S. pointed to a chicken with his right hand and a snow shovel with his left.
''I'll never forget the day we got around to asking P.S., 'Why did you do that?''' said Dr. Gazzaniga. ''He said, 'The chicken claw goes with the chicken.' That's all the left hemisphere saw. And then he looks at the shovel and said, 'The reason you need a shovel is to clean out the chicken shed.'''
Dr. Gazzaniga hypothesized that P.S.'s left hemisphere made up a story to explain his actions, based on the limited information it received. Dr. Gazzaniga and his colleagues have carried out the same experiment hundreds of times since, and the left hemisphere has consistently acted this way.
''The interpreter tells the story line of a person,'' Dr. Gazzaniga said. ''It's collecting all the information that is in all these separate systems that are distributed through the brain.'' While the story feels like an unfiltered picture of reality, it's just a quickly-thrown-together narrative.
Experiments on split-brain patients reveal how readily the left brain interpreter can make up stories and beliefs. In one experiment, for example, when the word walk was presented only to the right side of a patient’s brain, he got up and started walking. When he was asked why he did this, the left brain (where language is stored and where the word walk was not presented) quickly created a reason for the action: 'I wanted to go get a Coke.'
So storytelling is on the left side. It’s generating an ‘afterthought’. But does this also imply that our cognition and our consciousness are in this same area? Is all linguistic processing in this area? What about this woman who could still write with her left hand.
Kathleen B. Baynes of the University of California at Davis reports another unique case. A left-handed patient spoke out of her left brain after split-brain surgery - not a surprising finding in itself. But the patient could write only out of her right, nonspeaking hemisphere. This dissociation confirms the idea that the capacity to write need not be associated with the capacity for phonological representation. Put differently, writing appears to be an independent system, an invention of the human species. It can stand alone and does not need to be part of our inherited spoken language system.
Did her writing still have a storyline? Or was she just writing down what she heard? It could be that the story telling is not specific for the left. But that only the speech part is. That is not really surprising. It would give problems if both hemispheres control speech. That would be speech with a double tongue.
Ah!! Still so many questions. But I getting more convinced that our storyteller is important to give meaning to our life. Or is it just telling stories, because it is the only thing it can do. Just like apples falling from the tree? Life has a meaning, because the storyteller tell so?
Dr. Gazzaniga and Dr. LeDoux showed P.S. a picture of a chicken claw in his right eye and a snow-covered house in the left eye. P.S. pointed to a chicken with his right hand and a snow shovel with his left.
''I'll never forget the day we got around to asking P.S., 'Why did you do that?''' said Dr. Gazzaniga. ''He said, 'The chicken claw goes with the chicken.' That's all the left hemisphere saw. And then he looks at the shovel and said, 'The reason you need a shovel is to clean out the chicken shed.'''
Dr. Gazzaniga hypothesized that P.S.'s left hemisphere made up a story to explain his actions, based on the limited information it received. Dr. Gazzaniga and his colleagues have carried out the same experiment hundreds of times since, and the left hemisphere has consistently acted this way.
''The interpreter tells the story line of a person,'' Dr. Gazzaniga said. ''It's collecting all the information that is in all these separate systems that are distributed through the brain.'' While the story feels like an unfiltered picture of reality, it's just a quickly-thrown-together narrative.
Experiments on split-brain patients reveal how readily the left brain interpreter can make up stories and beliefs. In one experiment, for example, when the word walk was presented only to the right side of a patient’s brain, he got up and started walking. When he was asked why he did this, the left brain (where language is stored and where the word walk was not presented) quickly created a reason for the action: 'I wanted to go get a Coke.'
From The Ethical Brain by Michael Gazzaniga
So storytelling is on the left side. It’s generating an ‘afterthought’. But does this also imply that our cognition and our consciousness are in this same area? Is all linguistic processing in this area? What about this woman who could still write with her left hand.
Kathleen B. Baynes of the University of California at Davis reports another unique case. A left-handed patient spoke out of her left brain after split-brain surgery - not a surprising finding in itself. But the patient could write only out of her right, nonspeaking hemisphere. This dissociation confirms the idea that the capacity to write need not be associated with the capacity for phonological representation. Put differently, writing appears to be an independent system, an invention of the human species. It can stand alone and does not need to be part of our inherited spoken language system.
From The Split Brain Revisited by Michael S. Gazzaniga
Did her writing still have a storyline? Or was she just writing down what she heard? It could be that the story telling is not specific for the left. But that only the speech part is. That is not really surprising. It would give problems if both hemispheres control speech. That would be speech with a double tongue.
Ah!! Still so many questions. But I getting more convinced that our storyteller is important to give meaning to our life. Or is it just telling stories, because it is the only thing it can do. Just like apples falling from the tree? Life has a meaning, because the storyteller tell so?
# posted by Sander @ 23:50 
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Hi Sander
(Let's start by bragging a bit) I once asked Gazzaniga a question after he gave a talk (in Nijmegen). Upon which he he said: That is a good question. You might be interested in this moveie. Upon which he showed a movie that had nothing to do with my question - he had planned to show the movie regardless of the content of the question. Next - he said: enough hard questions, let;s get to the bar.
I don't really like Gazzaniga. But I do have a cool movie of one of his split-brain patients, I got it from the web somewhere - I'll have to look it up.
Anyway, actually, Gazzaniga feels that our storyteller sort of fools us into thinking that there is somebody up there in our head 'pulling the strings'. This is the person we usually refer to as "I" or "me". This person, the one that uses our inner thought and, more broadly, constitutes our consciousness, leads us to believe that s/he is the one that is "doing" the things we do.
Whereas *in fact* it is our brain that is doing those things even before the storyteller has had a chance in constructing the story in which our conscious self *decides* to do the act.
Read again:
We already are executing an action even before our conscious self *decides* to act that action.
There is considerable evidence for this. Gazzaniga told us about chess players who decided in split-second and then go on to tell lengthy stories about the reasons for acting the way they did. Munching over all these considerations in real-time would have made reactiontimes much slower for these players than they actually were.
But Gazzaniga himself is not the main player in this area (although he would like to be so I guess) Early work on the 'illusion' of conscious will was already done by Libet and recently there was a good book on it by Wegner
So, not only is the storyteller important, it is also necessary in order not to get us completely depressed about realising that we are in fact not in control of our own actions - which would make life rather pointless in a way - which brings us back to your own conclusion
(Let's start by bragging a bit) I once asked Gazzaniga a question after he gave a talk (in Nijmegen). Upon which he he said: That is a good question. You might be interested in this moveie. Upon which he showed a movie that had nothing to do with my question - he had planned to show the movie regardless of the content of the question. Next - he said: enough hard questions, let;s get to the bar.
I don't really like Gazzaniga. But I do have a cool movie of one of his split-brain patients, I got it from the web somewhere - I'll have to look it up.
Anyway, actually, Gazzaniga feels that our storyteller sort of fools us into thinking that there is somebody up there in our head 'pulling the strings'. This is the person we usually refer to as "I" or "me". This person, the one that uses our inner thought and, more broadly, constitutes our consciousness, leads us to believe that s/he is the one that is "doing" the things we do.
Whereas *in fact* it is our brain that is doing those things even before the storyteller has had a chance in constructing the story in which our conscious self *decides* to do the act.
Read again:
We already are executing an action even before our conscious self *decides* to act that action.
There is considerable evidence for this. Gazzaniga told us about chess players who decided in split-second and then go on to tell lengthy stories about the reasons for acting the way they did. Munching over all these considerations in real-time would have made reactiontimes much slower for these players than they actually were.
But Gazzaniga himself is not the main player in this area (although he would like to be so I guess) Early work on the 'illusion' of conscious will was already done by Libet and recently there was a good book on it by Wegner
So, not only is the storyteller important, it is also necessary in order not to get us completely depressed about realising that we are in fact not in control of our own actions - which would make life rather pointless in a way - which brings us back to your own conclusion
Hmmmm Jelle.... do you have (neurofysiological) proof of your statements?
I do not agree with the things you write here. The *in fact* is a little to self confident for me. As long as there is no _proof_ this "theory" it stays an unproven theory. We for *a fact* don't know what "conscious self" is related to in the brain let alone the human body.
Can you give me some references to the evidence you are talking about?
The evidence I know of is neurofysiological and is only related to reaction time not to any concept of consciousness. Evidence is for me is more than a lot of people who are accepting an idea or concept.
Futhermore much of the processing before an action is taken goes in paralel in the brain. So it is very difficult to talk about "before" and "after" in terms of constructing ideas and acting on them.
Love to get a reaction on this :-)
Greets,
Bob
I do not agree with the things you write here. The *in fact* is a little to self confident for me. As long as there is no _proof_ this "theory" it stays an unproven theory. We for *a fact* don't know what "conscious self" is related to in the brain let alone the human body.
Can you give me some references to the evidence you are talking about?
The evidence I know of is neurofysiological and is only related to reaction time not to any concept of consciousness. Evidence is for me is more than a lot of people who are accepting an idea or concept.
Futhermore much of the processing before an action is taken goes in paralel in the brain. So it is very difficult to talk about "before" and "after" in terms of constructing ideas and acting on them.
Love to get a reaction on this :-)
Greets,
Bob
With respect to our consciousness I am wondering if there is even a theoretical possibility give strong proofs. I've got a feeling that there is a problem with self-reference that reminds me of Gödels incompleteness theorems.
There is either no proof, or the proof results in an inconsistency.
Looking into this I found a reference to Minds, Machines an Gödel that addresses the point of computability of the mind. But I think I need some more training to understand this problem. Could you guys give a review for a layman?
Another interesting point to think about is the singleness of consciousness. Am not aware of a situation with multiple consciousnesses...
I still don't know whether how strong the relation is between our storyteller and our consciousness... Are they related? Are they the same?
Maybe not. You can be aware of something that you are not able to put into words.
Finally I think that our storyteller is not just babbling. It's making up stories to make sense out of the things that happen. But the fact of giving meaning to something also leaves an imprint in our subconsciousness. Next time in the same situation we might react differently, just because of the story we created last time. It's a slow feedback mechanism.
There is either no proof, or the proof results in an inconsistency.
Looking into this I found a reference to Minds, Machines an Gödel that addresses the point of computability of the mind. But I think I need some more training to understand this problem. Could you guys give a review for a layman?
Another interesting point to think about is the singleness of consciousness. Am not aware of a situation with multiple consciousnesses...
I still don't know whether how strong the relation is between our storyteller and our consciousness... Are they related? Are they the same?
Maybe not. You can be aware of something that you are not able to put into words.
Finally I think that our storyteller is not just babbling. It's making up stories to make sense out of the things that happen. But the fact of giving meaning to something also leaves an imprint in our subconsciousness. Next time in the same situation we might react differently, just because of the story we created last time. It's a slow feedback mechanism.
Hi,
Well, I don't know myself whether I accept the conclusion by Libet and Wegner (google on either of these two together with consciousness, bobob, Wegner wrote a book on it: the illusion of conscious will), but "facts" are that we have motor preparation for acts that we have not yet 'decided to execute' in the first place. Which is intriguing at the least.
Anyway the relation between consciousness and the brain is to me rather straightforward: if you take away my foot I am still here, if you take away my brain I'm gone. According to Dennett the question then becomes whether I am in my brain or still in my body, I guess I am no longer existent at all once you seperate the vehicle and it's control system. I do not believe in reincarnation and life after death, perhaps this is what you refer to, but that is beyond proof anyhow so it makes little sense to discuss that mixed with science-based arguments. But perhaps I'm too simple on this one.
Sander:
> more training to understand this problem. Could you guys give a review for a layman?
Iris knows some about noncomputability. I could refer you to her email if you really want to read up on it.
> Another interesting point to think about is the singleness of consciousness. Am not aware of a situation with multiple consciousnesses...
This is discussed in Edelman and Tononi 2000 a universe of consciousness. It is one of their criteria to decide whether consciousness is present or not (unicity). Read the oft-cited review (not!) of their book by me and Gert-Jan: Dijk & Bleeker, in Cog Sys Research: Review of ... A universe of consciousness
>
Maybe not. You can be aware of something that you are not able to put into words.
So there is a difference between consciousness and awareness, i guess?
> Finally I think that our storyteller is not just babbling. It's making up stories to make sense out of the things that happen. But the fact of giving meaning to something also leaves an imprint in our subconsciousness. Next time in the same situation we might react differently, just because of the story we created last time. It's a slow feedback mechanism.
This is completely true, I agree on this. Especially your last sentence: slow feedback mechanism. But it would mean that it doesn't act *now*, it only acts implicitly, in learning/adaptation. Another mechanism might be that explicit cognitive deliberation (rational analysis) might help to suppress strong emotions and inhibit unwanted impulses (the prefrontal cortex might do this).
Well, I don't know myself whether I accept the conclusion by Libet and Wegner (google on either of these two together with consciousness, bobob, Wegner wrote a book on it: the illusion of conscious will), but "facts" are that we have motor preparation for acts that we have not yet 'decided to execute' in the first place. Which is intriguing at the least.
Anyway the relation between consciousness and the brain is to me rather straightforward: if you take away my foot I am still here, if you take away my brain I'm gone. According to Dennett the question then becomes whether I am in my brain or still in my body, I guess I am no longer existent at all once you seperate the vehicle and it's control system. I do not believe in reincarnation and life after death, perhaps this is what you refer to, but that is beyond proof anyhow so it makes little sense to discuss that mixed with science-based arguments. But perhaps I'm too simple on this one.
Sander:
> more training to understand this problem. Could you guys give a review for a layman?
Iris knows some about noncomputability. I could refer you to her email if you really want to read up on it.
> Another interesting point to think about is the singleness of consciousness. Am not aware of a situation with multiple consciousnesses...
This is discussed in Edelman and Tononi 2000 a universe of consciousness. It is one of their criteria to decide whether consciousness is present or not (unicity). Read the oft-cited review (not!) of their book by me and Gert-Jan: Dijk & Bleeker, in Cog Sys Research: Review of ... A universe of consciousness
>
Maybe not. You can be aware of something that you are not able to put into words.
So there is a difference between consciousness and awareness, i guess?
> Finally I think that our storyteller is not just babbling. It's making up stories to make sense out of the things that happen. But the fact of giving meaning to something also leaves an imprint in our subconsciousness. Next time in the same situation we might react differently, just because of the story we created last time. It's a slow feedback mechanism.
This is completely true, I agree on this. Especially your last sentence: slow feedback mechanism. But it would mean that it doesn't act *now*, it only acts implicitly, in learning/adaptation. Another mechanism might be that explicit cognitive deliberation (rational analysis) might help to suppress strong emotions and inhibit unwanted impulses (the prefrontal cortex might do this).
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