The following video (in German) is particularly good.
The following is a link to the original French version
Showing posts with label Psychology. Show all posts
Showing posts with label Psychology. Show all posts
Sunday, 19 June 2011
Spinosa and understanding
Spinosa had it right before almost everybody. And yes, understanding is the way. Saying to a child that sugar is bad for its teeth is not the way. We need to explain them how sugar feed the bacteria that produce the acid that dissolve the enamel of the teeth...
The following video (in German) is particularly good.
The following video (in German) is particularly good.
Wednesday, 6 April 2011
Book Review: Sight Unseen (M.goodale, A. Milner) Part II:Doing without seeing
Now you will be surprised! You remember that Dee was unable to see the shape of things? Well, as it turns out, if you show her a pencil, she is unable to say what it is, let alone if it is held vertically or horizontally. However, ask her to grasp it and she will grasp it just like anybody else! With the same "on the fly" right orienting of her hand and with the same "on the fly" narrowing of her thumb - index distance! Just like if she could see it!
Just as surprising: She can walk around in a landscape full of obstacles without ever stumbling on any! She avoids them all like you and me!
The authors presented her a mailbox which opening was rotatable so as to enable orienting it in any chosen direction. When Dee was asked to hold an envelope and to rotate the envelope in such a way as to match with the opening of the mailbox: She failed lamentably. She seemed to orient her envelop randomly. But when asked to post the envelop through the slit: she succeeded easily, orienting correctly her hand just like you and me!
The authors asked her to grasp various objects while captors where posed at various parts of her hand so as to be able to analyze finely her moves. She grasps things in the exact same way as anybody else: adapting the orientation of her hand on the fly and adjusting the thumb-index distance to the size of the object! Objects that she cannot "see" and which dimensions she is unable to guess!
As it turns out, Dee has the part of her vision controlling her actions intact but has the part of her vision constructing her perceptual representations damaged. She is living evidence that part of our vision driven actions are unconscious. We do not need to be aware of the orientation of a slit to be able to slide something in it. However, we do need to be aware of the orientation of said slit to be able to describe it!
We have many independent visually controlled processes in our brain. Many of them (grasping things, walking around avoid things, ...) still work even when, like Dee, we have lost the ability to consciously see these things!
In my next post, you will see how some people have the exact opposite problem than Dee.
Just as surprising: She can walk around in a landscape full of obstacles without ever stumbling on any! She avoids them all like you and me!
The authors presented her a mailbox which opening was rotatable so as to enable orienting it in any chosen direction. When Dee was asked to hold an envelope and to rotate the envelope in such a way as to match with the opening of the mailbox: She failed lamentably. She seemed to orient her envelop randomly. But when asked to post the envelop through the slit: she succeeded easily, orienting correctly her hand just like you and me!
The authors asked her to grasp various objects while captors where posed at various parts of her hand so as to be able to analyze finely her moves. She grasps things in the exact same way as anybody else: adapting the orientation of her hand on the fly and adjusting the thumb-index distance to the size of the object! Objects that she cannot "see" and which dimensions she is unable to guess!
As it turns out, Dee has the part of her vision controlling her actions intact but has the part of her vision constructing her perceptual representations damaged. She is living evidence that part of our vision driven actions are unconscious. We do not need to be aware of the orientation of a slit to be able to slide something in it. However, we do need to be aware of the orientation of said slit to be able to describe it!
We have many independent visually controlled processes in our brain. Many of them (grasping things, walking around avoid things, ...) still work even when, like Dee, we have lost the ability to consciously see these things!
In my next post, you will see how some people have the exact opposite problem than Dee.
Monday, 21 March 2011
Book Review: Consciousness explained.Part VII. The evolution of consciousness
Daniel Dennett proposes the following evolutionary scenario for consciousness:
1) In the environment on earth before the appearence of life, some molecules acquired the ability to replicate (Richard Dawkins would call them replicators). This creates a point of view from which the world's events can be roughly partitioned between the favorable to this replication, unfavorable to it or the neutral".
2) "As soon as something gets into the business of self-preservation, boundaries become important, for if you are setting out to preseerve yourself, you don't want to squander effort trying to preserve the whole world: you draw the line."
3)Next in line comes a certain ability to react to direct stimuli upon contact. E.g. engulfing food you touch or coiling away from harmful things you touch. This is the most rudimentary type of nervous response. It is a very crude way to predict the future. If I don't recoil, I will get eaten/destroyed/damaged.
4)Next, comes short range anticipations like the ducking reflex that permits to avoid being hurt be a projectile. Such reflexes are hard wired, including in humans (newborn infants have it). An interesting fact Dennett points out is the ability of many animals (from fish to humans) to be particularly sensible to the presence of a vertical axis of symmetry in its visual field. This is presumably caused by the fact that in our evolutionary past the most likely item in our environment having such an axis would have been a predator, a prey or a mate facing you. He argues that the fact that such alarm mechanisms are so crude, has the advantage of being fast and economical at the cost of many false alarms (the vision of a quasi symetrical tree for instance). For such a trick to be selected by evolution, it only has to give to its owner a slightly higher than otherwise chance to survive or to mate.
5) Once such a signal is detected, a further evolutionary advantage is achieved by a discrimination process capable to determine (at least in a crude way) if the first crude signal was a predator, a prey or a mate. In some fish, the vertical symmetry signal triggers an "orienting response", i.e. a swift interuption of ongoing activity. Dennett says that we have many such subsystems running unconsciously and performing specialized tasks.
When an alarm signal is recieved, e.g. due to the perceiving of symetry, our system stops and all our senses are open to maximize the input of information. If the alarm is confirmed, we get a rush of adrenaline and we react by e.g. fleeing. He says monst animals have such a system and he sees such "orienting responses" as a precursor to what we call our state of conscious awareness.
6) The animal acquired the ability to trigger such an "orienting reponse" also as a consequence of internal stimulis (not only external inputs such as symetric objects).
7) "Regular vigilance" turned into "regular exploration" where the animal frequently acquire information for its own sake, just in case it turns out useful in the future. E.g. primates with their saccaded eye movements scan uninteruptly their environment.
That's already a nice start I think...
1) In the environment on earth before the appearence of life, some molecules acquired the ability to replicate (Richard Dawkins would call them replicators). This creates a point of view from which the world's events can be roughly partitioned between the favorable to this replication, unfavorable to it or the neutral".
2) "As soon as something gets into the business of self-preservation, boundaries become important, for if you are setting out to preseerve yourself, you don't want to squander effort trying to preserve the whole world: you draw the line."
3)Next in line comes a certain ability to react to direct stimuli upon contact. E.g. engulfing food you touch or coiling away from harmful things you touch. This is the most rudimentary type of nervous response. It is a very crude way to predict the future. If I don't recoil, I will get eaten/destroyed/damaged.
4)Next, comes short range anticipations like the ducking reflex that permits to avoid being hurt be a projectile. Such reflexes are hard wired, including in humans (newborn infants have it). An interesting fact Dennett points out is the ability of many animals (from fish to humans) to be particularly sensible to the presence of a vertical axis of symmetry in its visual field. This is presumably caused by the fact that in our evolutionary past the most likely item in our environment having such an axis would have been a predator, a prey or a mate facing you. He argues that the fact that such alarm mechanisms are so crude, has the advantage of being fast and economical at the cost of many false alarms (the vision of a quasi symetrical tree for instance). For such a trick to be selected by evolution, it only has to give to its owner a slightly higher than otherwise chance to survive or to mate.
5) Once such a signal is detected, a further evolutionary advantage is achieved by a discrimination process capable to determine (at least in a crude way) if the first crude signal was a predator, a prey or a mate. In some fish, the vertical symmetry signal triggers an "orienting response", i.e. a swift interuption of ongoing activity. Dennett says that we have many such subsystems running unconsciously and performing specialized tasks.
When an alarm signal is recieved, e.g. due to the perceiving of symetry, our system stops and all our senses are open to maximize the input of information. If the alarm is confirmed, we get a rush of adrenaline and we react by e.g. fleeing. He says monst animals have such a system and he sees such "orienting responses" as a precursor to what we call our state of conscious awareness.
6) The animal acquired the ability to trigger such an "orienting reponse" also as a consequence of internal stimulis (not only external inputs such as symetric objects).
7) "Regular vigilance" turned into "regular exploration" where the animal frequently acquire information for its own sake, just in case it turns out useful in the future. E.g. primates with their saccaded eye movements scan uninteruptly their environment.
That's already a nice start I think...
Saturday, 19 March 2011
Do you find this video relaxing?
Put the audio level low. This is an experimental video making use of our "orienting response reflex" by presenting to us new information every 2.5 seconds. During the "orienting response" which is a mental state in which most animal find themeselves when presented with something new, our heart rate is decreased and our brain blood vessels dialtes in order to increase our brain readiness to acquire information in order to react vis-à-vis this "something new". This vidéo is from ansgar1965 and is experimental (not tested, you are the cobayes. So what do you think? is it relaxing?)
Sunday, 13 March 2011
Consciousness Explained: the contribution of a reader
I received an interesting comment from a reader (Jason Weber) that shed some more light on this book:
"I definitely suggest reading Sweet Dreams
: it is very well written."
: it is very well written." -I will order it…and read it in two or three years probably
"I took a look at your blog and enjoyed reading Part V of your book review."
-Glad to hear that.
"I have a question and a few comments if you do not mind. First off, what page did you find the quote for Dennett's alternative explanation for delay in consciousness?"
- p.164, 3rd§, line 2 : « Orwellian alternative »
"I ask because this sounds more like an "Orwellian revision" than Dennett's model for consciousness.
As I understand it, he does not support either an Orwellian or Stalinesque explanation, "...and the question Orwellian or Stalinesque? (post experiential or pre-experiential) need have no answer" (Dennett, Time and the Observer, http://ase.tufts.edu/cogstud/papers/time&obs.htm )."
-You are right that Dennett does not support either Orwellian or Stallinesque alternatives. I think I was wrong when I said that it is “his alternative explanation”. Actually he simply remarks that there is an Orwellian alternative to the Stallinesque model. Which I suppose makes his point that both explanations are possible, which is pointing to his multiple draft model.
"Thank you for bringing your blog to my attention, because I had forgotten how vehemently Dennett disagreed with Libet on the interpretation of those experiments."
-Strangely enough, I myself already read twice this part of the book and also forgot about it. Then I heard again about Libet type experiments and got quite excited about them, without realizing that I read a critique of them in Dennett. This really justifies my present effort to document what I understand from this book.
"Those experiments are very interesting to me and I had taken them at face value for a while."
-They are very interesting to me too. I am sympathetic to the idea that actions are decided before to be consciously felt as being decided…although I feel my confidence shaking a bit while reading this book.
"Your blog helped me to focus on some mistakes I had made. I do think that the unconscious parts of the brain plays a role in determining consciousness…"
-me too. I agree with Dennett that consciousness is probably distributed in the brain and that each location that get conscious, was not necessarily so the instant before. No single area for consciousness experience (I would have said otherwise six months ago. I might still change my mind ).
"…but that Libet's results and interpretations need a closer examination. Dennett provides that, so let me try to clear up exactly what Dennett does not like about Libet's experiments....
Daniel Dennett's criticisms of Benjamin Libet's famous experiment on intentionality:
In principle, I do not believe that Dennett disagrees with the notion that unconscious parts of the brain cause consciousness."-you are right
"He disagrees that attaining an absolute timing of conscious events from verbal reports is possible because consciousness does not happen in a centralized location in the brain.
That is the disagreement. Dennett notes that the representations of visual events occur, "...in various different parts of the brain, starting at the retina and moving up through the visual system...brightness...is represented in some places and times...location in others...and motion in still others" (Consciousness Explained, p.165).
Consciousness comes from many parts of the brain. For instance, he does not seem to believe that a single neuron or a single system in the brain possesses the state of consciousness all the time."
-It seems to me that it is indeed his position but I have a hard time understanding why the lack of a central location for consciousness prevents absolute timing of conscious events. Even if a conscious event appears distributed in space or at a location only temporarily made conscious, timing seems still possible.
"It follows that unconscious parts of the brain cause consciousness or change to the state of consciousness."
-indeed
"Dennett disagree with Libet because of his interpretation that the unconscious parts send there messages to a central conscious part of the brain."
-ok, I would need to re-read this part to check that it is indeed what Libet thinks and not Dennett’s interpretation of what Libet thinks. I think that even by abandoning the Cartesian theater, it is still coherent to interpret the results of the experiment by saying that the conscious “feeling” that a decision is made is felt after the decision. E.g. the decision is made due to a certain number of neurons being turned on at various locations…and 350 ms later we feel it because these locations changed “state” or maybe (my hypothesis) because this event “get burned” thereby creating a memory (at these same locations, e.g. by strengthening connections).
"Dennett states that, "...cognition and control -- and hence consciousness -- is distributed around in the brain, no moment can count as the precise moment at which each conscious event happens" (Consciousness Explained, p. 169). If measuring the absolute timing of a conscious event is possible, then we must assume that consciousness happens in one place and at one time in the brain."
-Not one place, only one time. No? Even if spatially distributed, it could be simultaneous or within a time relatively short compared to the delay observed by Libet.
"Dennett's model differs, not because unconscious agents cause consciousness but, because consciousness is not thrown together in one spot in the brain (e.g. the pineal gland). For Dennett, different systems contain different parts of the stories that make up consciousness but there is no place where representations come together to form a central conscious story of events."
-That is well understood.
"The most telling quote from Dennett in the chapter of Consciousness Explained that discusses Libet's experiment is this,
-I like this idea. It makes sense to me. I think consciousness intensity and memorization intensity are linked. Being conscious could be what it “feels” to memorize.
"The state change Dennett mentions is key: it is not that he believes that every part of the brain that has the capacity for consciousness is always conscious. I take it that he means that those parts change state from unconscious to conscious but do not do so until they receive enough clout to contribute to the distributed conscious experience. As different parts of the brain become conscious, the story changes; I think that is what Dennett means by multiple drafts."
-I think you are right and I think I now understand better this chapter. Thanks! I will re-read it nevertheless to be sure my new understanding fits with what he writes.
"Chapter six is difficult to understand so I hope I am properly representing Dennett's theory above. Feel free to correct me or to ask questions. Thank you,"
"Thank you for bringing your blog to my attention, because I had forgotten how vehemently Dennett disagreed with Libet on the interpretation of those experiments."
-Strangely enough, I myself already read twice this part of the book and also forgot about it. Then I heard again about Libet type experiments and got quite excited about them, without realizing that I read a critique of them in Dennett. This really justifies my present effort to document what I understand from this book.
"Those experiments are very interesting to me and I had taken them at face value for a while."
-They are very interesting to me too. I am sympathetic to the idea that actions are decided before to be consciously felt as being decided…although I feel my confidence shaking a bit while reading this book.
"Your blog helped me to focus on some mistakes I had made. I do think that the unconscious parts of the brain plays a role in determining consciousness…"
-me too. I agree with Dennett that consciousness is probably distributed in the brain and that each location that get conscious, was not necessarily so the instant before. No single area for consciousness experience (I would have said otherwise six months ago. I might still change my mind ).
"…but that Libet's results and interpretations need a closer examination. Dennett provides that, so let me try to clear up exactly what Dennett does not like about Libet's experiments....
Daniel Dennett's criticisms of Benjamin Libet's famous experiment on intentionality:
In principle, I do not believe that Dennett disagrees with the notion that unconscious parts of the brain cause consciousness."-you are right
"He disagrees that attaining an absolute timing of conscious events from verbal reports is possible because consciousness does not happen in a centralized location in the brain.
That is the disagreement. Dennett notes that the representations of visual events occur, "...in various different parts of the brain, starting at the retina and moving up through the visual system...brightness...is represented in some places and times...location in others...and motion in still others" (Consciousness Explained, p.165).
Consciousness comes from many parts of the brain. For instance, he does not seem to believe that a single neuron or a single system in the brain possesses the state of consciousness all the time."
-It seems to me that it is indeed his position but I have a hard time understanding why the lack of a central location for consciousness prevents absolute timing of conscious events. Even if a conscious event appears distributed in space or at a location only temporarily made conscious, timing seems still possible.
"It follows that unconscious parts of the brain cause consciousness or change to the state of consciousness."
-indeed
"Dennett disagree with Libet because of his interpretation that the unconscious parts send there messages to a central conscious part of the brain."
-ok, I would need to re-read this part to check that it is indeed what Libet thinks and not Dennett’s interpretation of what Libet thinks. I think that even by abandoning the Cartesian theater, it is still coherent to interpret the results of the experiment by saying that the conscious “feeling” that a decision is made is felt after the decision. E.g. the decision is made due to a certain number of neurons being turned on at various locations…and 350 ms later we feel it because these locations changed “state” or maybe (my hypothesis) because this event “get burned” thereby creating a memory (at these same locations, e.g. by strengthening connections).
"Dennett states that, "...cognition and control -- and hence consciousness -- is distributed around in the brain, no moment can count as the precise moment at which each conscious event happens" (Consciousness Explained, p. 169). If measuring the absolute timing of a conscious event is possible, then we must assume that consciousness happens in one place and at one time in the brain."
-Not one place, only one time. No? Even if spatially distributed, it could be simultaneous or within a time relatively short compared to the delay observed by Libet.
"Dennett's model differs, not because unconscious agents cause consciousness but, because consciousness is not thrown together in one spot in the brain (e.g. the pineal gland). For Dennett, different systems contain different parts of the stories that make up consciousness but there is no place where representations come together to form a central conscious story of events."
-That is well understood.
"The most telling quote from Dennett in the chapter of Consciousness Explained that discusses Libet's experiment is this,
"Couldn't consciousness be a matter not of arrival at a point but rather a matter of representation exceeding some threshold of activation over the whole cortex or large parts thereof? On this model, an element of content becomes conscious at some time t, not by entering some functionally defined and anatomically located system, but by changing state right where it is: by acquiring some property or by having the intensity of one of its properties boosted above some threshold"(p. 166)."
-I like this idea. It makes sense to me. I think consciousness intensity and memorization intensity are linked. Being conscious could be what it “feels” to memorize.
"The state change Dennett mentions is key: it is not that he believes that every part of the brain that has the capacity for consciousness is always conscious. I take it that he means that those parts change state from unconscious to conscious but do not do so until they receive enough clout to contribute to the distributed conscious experience. As different parts of the brain become conscious, the story changes; I think that is what Dennett means by multiple drafts."
-I think you are right and I think I now understand better this chapter. Thanks! I will re-read it nevertheless to be sure my new understanding fits with what he writes.
"Chapter six is difficult to understand so I hope I am properly representing Dennett's theory above. Feel free to correct me or to ask questions. Thank you,"
ase.tufts.edu
Two models of consciousness are contrasted with regard to their treatment of subjective timing. The standard Cartesian Theater model postulates a place in the brain where "it all comes together": where the discriminations in all modalities are somehow put into registration and "presented" for sub
ShareHere is part of a message of reply from Jason:
"...This might help to illuminate why Dennett is suspect of absolute timing of subjective experience:
In the last paragraph, I say that the "....state change Dennett mentions is key..." That is not exactly true. In fact, he warns that this view could lead us back to the Cartesian Theater, "...if it is claimed that the real...timing of such mode shifts is definitive of subjective sequence" (Dennett, Consciousness Explained, p. 166). His key point in chapter six of the book is that the, "...temporal sequence in consciousness is...purely a matter of the content represented, not the timing of the representing (Dennett & Kinsbourne, Time and the Observer, http://ase.tufts.edu/cogstud/papers/time&obs.htm ). Let's imagine an analogy to explore this point: mom is coming to visit you. Let's say that she decides Friday that she is coming to visit you on Monday. She sends you an email detailing her decision. Unfortunately, you do not check your email all weekend. Then, when Monday comes, you are utterly surprised to see your mom's smiling face when you open your front door. You then check your email and discover the news or your mother's decision to visit that day. The timing was such that you did not find out the news that your mother was visiting on Monday until she showed up on your doorstep. However, the decision was made and the message was sent earlier (i.e. Friday). This is why Dennett & Kinsbourne indicate that, "...temporal... details do not tell us directly about the contents of consciousness" (Time and the Observer, http://ase.tufts.edu/cogstud/papers/time&obs.htm ). Just because a message is sent does not mean we instantly become aware of it subjectively.
On your comment: "-ok, I would need to re-read this part to check that it is indeed what Libet thinks and not Dennett’s interpretation of what Libet thinks."
--I think you are correct that it is Dennett's interpretation of what Libet thinks.
-Thank you very much for your comments, they were helpful. Thank you also for accepting me posting your message on this blog.
Christophe
Book Review: Consciousness Explained (D. Dennett): Part VI:The Precognitive Carousel
Dennett reports an experiment made by Grey Walter. It consisted in presenting a carousel projector for showing slides to patients having electrodes implanted in the motor cortex of their brain. The patients were given a controller with a button for them to push on when they wanted to switch from one slide to the next. Actually, the controller was a dummy controler and the slides where changed in function of the signal received by the electrodes. The results? The patients experienced that the slide projector was anticipating their decisions. The slides would change just before they had decided to change them. This again seems to point to consciousness arising after that the decision is made. Dennett however once again express his view that timing of conscious events is not possible. an opinion of him that I still need to study further before to accept it or to reject it.
I received an interesting message on Facebook from a reader (Jason Weber). I will probably post it as a note to chapter V.
I received an interesting message on Facebook from a reader (Jason Weber). I will probably post it as a note to chapter V.
Wednesday, 9 March 2011
Book Review: Consciousness Explained (D. Dennett): part V : Delay of consciousness
In the 80's, Libet reported an experiment where subjects (wearing scalp electrodes) were asked to flex one hand at the wrist while noting the position of a moving spot at the precise time they formed the intention to flex. Afterwards, said subjects reported where the spot was at the moment they decided to flex their hand. The electrical measurements performed by the electrodes permited to determine that the subjects flexed their wrist 350 to 400 ms before the time indicated by the subject as being his time of intention to flex.
This experiment seems to indicate that we are conscious of the decisions made by our brain AFTER they have been made.
It seems to me that Dennett does not like this conclusion (although he does not express it explicitly) which seems to contradict the intuition that our conscious acts control our bodily motions.
He considers this kind of explanation as being stalinesque (i.e. presuming that the brain delays consciousness in order to be able to presents all the facts it wants to present in the order it wants them to be presented).
He points out that there is an alternative explanation: "the subjects were conscious of their intentions at an earlier moment, but this consciousness was wiped out of memory (or just revised) before they had a chance to recall it". He calls this kind of explanation "Orwellian" because history is re-writen after the facts.
Finally, he also points out that yet another explanation which is that "an element of content becomes conscious at some time t, not by entering some functionally defined and anatomically located system, but by changing state right where it is: by acquiring some property or by having the intensity of one of its properties boosted above some threshold."
Dennett seems to doubt very much the possibility to equal the time of reporting of the subject with the time of conscious experience.
Personally, I would call on Ockham's razor with such an issue: stick to the simplest hypothesis until proven otherwise. Hence, as far as I am concerned, this experiment seems to indicate that consciousness arises after the facts. Clinical cases like the case of Mrs. Dee in "sight unseen" are also pointing toward such an explanation.
I think Dennett doubly dislikes the results of this experiment. 1) as mentioned earlier, it places consciousness after the events and 2) it looks like we are watching a movie of our live in a cartesian theater (he despises the idea of the cartesian theater).
[this page has been amended on 12/03 after a reader pointed to me some errors of interpretation. Thanks to Jason]
Tuesday, 8 March 2011
My own opinion on "consciousness"
Consciousness and memory
I will try to explain what is my vision of what I think consciousness might encompass. I am sure I do not understand fully what consciousness is (otherwise I would not be reading and thinking so much about it). I however partly developed and partly stole ideas that, put together, gives me a hypothesis of what consciousness could be.
It all started I think in 2007 when I was driving back from a patent law course in Antwerp. It was dark, there was nothing on the radio and I thought "you have no opinion whatsoever on what consciousness could be. Why don't you try to make yourself one by developing it from first principles?"
And so I started to think about what was necessary for experiencing consciously something? I started to reason: "if I hear something (e.g. a word) I can be conscious of it. Why?" How do I know that I heard it? Answer:"because it is in my memory and I can retrieve it. If it was not there, I would not know I heard it".
Then I thought "OK! So what happens exactly when I hear a word, e.g. the word 'abracadabra'?"
I thought that I first hear each sound of the word and that my brain "recognises" it. So I first hear the beginning of a "a", then the end of a "a" then the beginning of a "b" and so on.
But what would happen if I did not have a good memory? I might forget the beginning of the word at the time I am hearing the end of the word and this word would not make sense to me but I would nevertheless be conscious. However if you ask me 10 seconds after having telling me the word "abracadabra" whether I heard it (actually I would not even understand your question and I would not be able to answer it... but let say for the sake of this thought experiment that my memorisation capacity was brought back to normal before you asked me this question), I would answer "no" since I would have forgotten this word already.
Now let's decrease my memory even further to a time span of let say one millisecond. I would hear the beginning of a "a", then forget it, than I would here the middle of the "a", then forget it, then I would hear the end of a "a", then forget it. I would have some kind of rolling consciousness with a very short time span. This would be so far from what we experience as human conscious beings that we can hardly still call that a conscious state.
What would we experience if our short time memory had a time span infinitesimally short? Or no memory at all? I claim that this would equal to not being conscious.
From this thought experiment, I concluded that without memory, no consciousness.
Puropose or cause of consciousness
I then proceeded to think "aha! Memory is necessary for consciousness. Could it be that consciousness evolved together or after memory? Could it be that consciousness serves a purpose linked to memory or that being conscious is what it feels like to memorise?".
I then realised that we can be more or less conscious. We can be very aware of something or almost not aware at all of this thing. For instance, I was driving since half an hour but I was only barely conscious of the road. At other times I am very conscious of the road. So what could be the purpose of something varying in intensity and potentially serving memory?
I thought BINGO! Consciousness with its varying levels of intensity could serve as labels! Consciousness of something with a particular level of intensity could be a "label" informing the memorisation processes of the brain on the importance of said thing. It could also be the other way around. Maybe we just experience stronger consciousness feeling for stronger memories.
For instance, you see a free lion in front of you: you will be VERY conscious of its presence and your brain will record very deeply (and forever) this information instantaneously in your long term memory.
Another example: you see a small stone on the road. Your eyes saw it. This information entered your short term memory but you will not be very conscious of it at all. As a result, your memorisation processes having received the "low consciousness" label associated with this stone, you will quickly forget it and you will never ever be able to recall it.
Actually, we are at any given time bombarded with thousands of inputs, both internal and external. Our senses are incessantly receiving information. If we had to memorise all of them vividly and for ever, our memory would be full in no time. We therefore need to rank information by order of importance, in other words: we need a filter. This filter might or might not be consciousness.
This information is important for our survival (e.g. uncaged lion) or our reproduction (e.g. sexy lady/man)? Our brain attaches the label "very conscious" to it and it gets written deep into our memory.
Is this information unimportant (e.g. one tic of a clock amongst many)? Our brain attaches the label "barely conscious" to it and this information will quickly be forgotten.
Actually, we could very easily replace the word "consciousness" by the word "attention" in the last part of my analysis above.
Also, I could make sense of the same insights by making the alternative hypothesis that a label (or filter) (which is not "consciousness" but well "attention") is attached to each input and what we "feel", i.e. what we are "conscious" of is the process of memorisation. When something is memorised, we are conscious of it. When it is deeply memorised, we feel deeply conscious of it.
Another facet of what I think consciousness is comes from experiments in experimental psychology which all tend to indicate that our brain already knows we will move our wrist before that we are ourselves aware that we will move our wrist (Libet et al, 1983). I think this kind of experimental results fit nicely with my vision above because when your arm moves, it is best for you to keep in memory that it did! As a result, this information is engraved in your memory and you are simultaneously conscious of it.
You are conscious of many things your body experience but you are feeling it "after the facts".
This vision of consciousness is also compatible with my vision of free will (there is no free will).
We are spectators of our own lives. Just like when we go to the movie: sometimes we really think we are living it. Well, we also really think that we are in charge of ourselves...but we are not. The illusion is however almost perfect. This illusion falls apart e.g. when lesion to the primary visual cortex occurs.
Imagine that in the future we would be able to watch a movie while simultaneously feeling and thinking absolutely all what the actor feels and think. We would very easily be convinced that WE are the actor and that the actor that WE are has free will.
Later I would like to make a post on these psychological experiments I referred to. I also would like to speak about split brains, phantom limbs, rubber hands, and Mrs. Dee (a woman whose brain has been damaged and whose case is detailed in the book "sight unseen").
I will try to explain what is my vision of what I think consciousness might encompass. I am sure I do not understand fully what consciousness is (otherwise I would not be reading and thinking so much about it). I however partly developed and partly stole ideas that, put together, gives me a hypothesis of what consciousness could be.
It all started I think in 2007 when I was driving back from a patent law course in Antwerp. It was dark, there was nothing on the radio and I thought "you have no opinion whatsoever on what consciousness could be. Why don't you try to make yourself one by developing it from first principles?"
And so I started to think about what was necessary for experiencing consciously something? I started to reason: "if I hear something (e.g. a word) I can be conscious of it. Why?" How do I know that I heard it? Answer:"because it is in my memory and I can retrieve it. If it was not there, I would not know I heard it".
Then I thought "OK! So what happens exactly when I hear a word, e.g. the word 'abracadabra'?"
I thought that I first hear each sound of the word and that my brain "recognises" it. So I first hear the beginning of a "a", then the end of a "a" then the beginning of a "b" and so on.
But what would happen if I did not have a good memory? I might forget the beginning of the word at the time I am hearing the end of the word and this word would not make sense to me but I would nevertheless be conscious. However if you ask me 10 seconds after having telling me the word "abracadabra" whether I heard it (actually I would not even understand your question and I would not be able to answer it... but let say for the sake of this thought experiment that my memorisation capacity was brought back to normal before you asked me this question), I would answer "no" since I would have forgotten this word already.
Now let's decrease my memory even further to a time span of let say one millisecond. I would hear the beginning of a "a", then forget it, than I would here the middle of the "a", then forget it, then I would hear the end of a "a", then forget it. I would have some kind of rolling consciousness with a very short time span. This would be so far from what we experience as human conscious beings that we can hardly still call that a conscious state.
What would we experience if our short time memory had a time span infinitesimally short? Or no memory at all? I claim that this would equal to not being conscious.
From this thought experiment, I concluded that without memory, no consciousness.
Puropose or cause of consciousness
I then proceeded to think "aha! Memory is necessary for consciousness. Could it be that consciousness evolved together or after memory? Could it be that consciousness serves a purpose linked to memory or that being conscious is what it feels like to memorise?".
I then realised that we can be more or less conscious. We can be very aware of something or almost not aware at all of this thing. For instance, I was driving since half an hour but I was only barely conscious of the road. At other times I am very conscious of the road. So what could be the purpose of something varying in intensity and potentially serving memory?
I thought BINGO! Consciousness with its varying levels of intensity could serve as labels! Consciousness of something with a particular level of intensity could be a "label" informing the memorisation processes of the brain on the importance of said thing. It could also be the other way around. Maybe we just experience stronger consciousness feeling for stronger memories.
For instance, you see a free lion in front of you: you will be VERY conscious of its presence and your brain will record very deeply (and forever) this information instantaneously in your long term memory.
Another example: you see a small stone on the road. Your eyes saw it. This information entered your short term memory but you will not be very conscious of it at all. As a result, your memorisation processes having received the "low consciousness" label associated with this stone, you will quickly forget it and you will never ever be able to recall it.
Actually, we are at any given time bombarded with thousands of inputs, both internal and external. Our senses are incessantly receiving information. If we had to memorise all of them vividly and for ever, our memory would be full in no time. We therefore need to rank information by order of importance, in other words: we need a filter. This filter might or might not be consciousness.
This information is important for our survival (e.g. uncaged lion) or our reproduction (e.g. sexy lady/man)? Our brain attaches the label "very conscious" to it and it gets written deep into our memory.
Is this information unimportant (e.g. one tic of a clock amongst many)? Our brain attaches the label "barely conscious" to it and this information will quickly be forgotten.
Actually, we could very easily replace the word "consciousness" by the word "attention" in the last part of my analysis above.
Also, I could make sense of the same insights by making the alternative hypothesis that a label (or filter) (which is not "consciousness" but well "attention") is attached to each input and what we "feel", i.e. what we are "conscious" of is the process of memorisation. When something is memorised, we are conscious of it. When it is deeply memorised, we feel deeply conscious of it.
Another facet of what I think consciousness is comes from experiments in experimental psychology which all tend to indicate that our brain already knows we will move our wrist before that we are ourselves aware that we will move our wrist (Libet et al, 1983). I think this kind of experimental results fit nicely with my vision above because when your arm moves, it is best for you to keep in memory that it did! As a result, this information is engraved in your memory and you are simultaneously conscious of it.
You are conscious of many things your body experience but you are feeling it "after the facts".
This vision of consciousness is also compatible with my vision of free will (there is no free will).
We are spectators of our own lives. Just like when we go to the movie: sometimes we really think we are living it. Well, we also really think that we are in charge of ourselves...but we are not. The illusion is however almost perfect. This illusion falls apart e.g. when lesion to the primary visual cortex occurs.
Imagine that in the future we would be able to watch a movie while simultaneously feeling and thinking absolutely all what the actor feels and think. We would very easily be convinced that WE are the actor and that the actor that WE are has free will.
Later I would like to make a post on these psychological experiments I referred to. I also would like to speak about split brains, phantom limbs, rubber hands, and Mrs. Dee (a woman whose brain has been damaged and whose case is detailed in the book "sight unseen").
Saturday, 5 March 2011
Book Review: Consciousness Explained (Daniel C. Dennett): part IV (his model of consciousness)
The main purpose of Dennett's book is to 1) refute the carthesian theater model of consciousness (see image below), and 2) introduce his own new model instead. He calls his new model the multiple drafts model.
The Cartesian Theater:
A representation of the carthesian theater model of consciousness is depicted below:
In this picture, we can see the head of a man looking at an egg being fried in a frying pan. Inside this man's brain, a screen is present where the vision of the man is projected for a smaller man to look at. The smaller man (or homonculus) is a methaphor for a central part in the brain where "consciousness happen".
The carthesian theater model assumes that their is a central "organ" in the brain where what happens is what you are conscious of. Its most naive form is the idea that a spectator must be present in the brain in order for the senses inputs to be experienced. Descarte for instance considered the pineal gland to be such a center from where the input of the senses could be transduced from mechanical signals (Descarte was not aware of the electrical nature of these signals) to spiritual meanings for the soul's benefit.
The Multiple Draft Model:
In this model, there is no centre where everything has to converge in order to be experienced. On the contrary, different conscious events are generated at different places in the brain. Each element within an event is discriminated only once. For instance, if you see a cow, the brain discriminate the presence of a large object, then it notice it is an animal, then that it is a cow. The discrimination and its fixation in the memory is enough for the phenomenum to be conscious (if probed).
What will be conscious will depend of the time of the probing. If you probe too early, you will only experience the diffuse presence of a large object. If you probe very late, you will have forgotten everything.
There is no need for the discriminated element to be sent or linked to a central theater. The conscious experience will originate from the locus of the discrimination. Also, each element is constantly updated/modified (e.g. interpreted, refined, partly erased, ...) due to interaction with the rest of the brain (pre-existing memories, new inputs, ...).
The multiple draft model makes"writing it down" in memory criterial for consciousness.
This can be best understood by looking at the color phi phenomenom at the bottom of this post (I do not insert it here because it is a moving image that would disturb your reading). To most people, the color phi phenomenom is experienced as a red spot traveling from left to right and changing color midway to become green. However (and you can easily convince yourself thereof by hiding one of both spots), it is in fact nothing of the sort. It is simply two fixed spots, one red and one green, the first blinking out of phase with respect to the second.
When experiencing the color phi phenomenom, the brain does not need to place intermediate spots after having experienced the second spot because there is no part of the brain present to "watch" these intermediate spots, your brain (i.e. you) just "knows" that the spot moved.
When remembering past events, you don't feel them happening again, you just know they happended. For instance, if you try to remember with as much details as possible the pain you experienced the last time you knocked your toes against an obstacle, you will not experience real pain, you will just realize that you "know" what kind of pain it was (which intensity, which location...).
His model makes a lot of sense but what remains unclear to me is the following:
At any given time our brain is processing a lot of inputs: external inputs from our various senses and internal inputs. We clearly do not feel conscious of them all. Cerrtainly, we do not feel conscious of many of them "simultaneously". Dennett seems however to say that whenever an object of our phenomenology is discriminated by our brain, it is "conscious".
On another hand he alludes to the notion of probing. Probing that would determine what is reported as conscious. He seems to make a difference between what is conscious and what we report as conscious experience when asked (i.e. probed) to report.
What I don't get is what he exactly means by his notion of "probing". I get it only partialy. I get it when by probing he means triggering a report from the conscious subject: e.g. asking the guy what he sees/feel. However, we are not constantly being asked to report on our internal states and we feel nevertheless conscious in these apparently "non-probed" times.
Of course, I suspect that his notion of what the probing is is more subtle than that. I suppose that internal inputs and external inputs can themeselves serve as "probes".
Maybe this notion is better explained in the rest of the book.
Once very important phrase he wrote is "The multiple draft model makes"writing it down" in memory criterial for consciousness".
I fully agree with the fact that writing something down in memory is critical for consciousness!
I have my own partial theory on consciousness and I should maybe explain it here before to continue Dennett's book. In view of the bold sentence above, I suspect that his views and mine overlap largly.
The Cartesian Theater:
A representation of the carthesian theater model of consciousness is depicted below:
In this picture, we can see the head of a man looking at an egg being fried in a frying pan. Inside this man's brain, a screen is present where the vision of the man is projected for a smaller man to look at. The smaller man (or homonculus) is a methaphor for a central part in the brain where "consciousness happen".
The carthesian theater model assumes that their is a central "organ" in the brain where what happens is what you are conscious of. Its most naive form is the idea that a spectator must be present in the brain in order for the senses inputs to be experienced. Descarte for instance considered the pineal gland to be such a center from where the input of the senses could be transduced from mechanical signals (Descarte was not aware of the electrical nature of these signals) to spiritual meanings for the soul's benefit.
The Multiple Draft Model:
In this model, there is no centre where everything has to converge in order to be experienced. On the contrary, different conscious events are generated at different places in the brain. Each element within an event is discriminated only once. For instance, if you see a cow, the brain discriminate the presence of a large object, then it notice it is an animal, then that it is a cow. The discrimination and its fixation in the memory is enough for the phenomenum to be conscious (if probed).
What will be conscious will depend of the time of the probing. If you probe too early, you will only experience the diffuse presence of a large object. If you probe very late, you will have forgotten everything.
There is no need for the discriminated element to be sent or linked to a central theater. The conscious experience will originate from the locus of the discrimination. Also, each element is constantly updated/modified (e.g. interpreted, refined, partly erased, ...) due to interaction with the rest of the brain (pre-existing memories, new inputs, ...).
The multiple draft model makes"writing it down" in memory criterial for consciousness.
This can be best understood by looking at the color phi phenomenom at the bottom of this post (I do not insert it here because it is a moving image that would disturb your reading). To most people, the color phi phenomenom is experienced as a red spot traveling from left to right and changing color midway to become green. However (and you can easily convince yourself thereof by hiding one of both spots), it is in fact nothing of the sort. It is simply two fixed spots, one red and one green, the first blinking out of phase with respect to the second.
When experiencing the color phi phenomenom, the brain does not need to place intermediate spots after having experienced the second spot because there is no part of the brain present to "watch" these intermediate spots, your brain (i.e. you) just "knows" that the spot moved.
When remembering past events, you don't feel them happening again, you just know they happended. For instance, if you try to remember with as much details as possible the pain you experienced the last time you knocked your toes against an obstacle, you will not experience real pain, you will just realize that you "know" what kind of pain it was (which intensity, which location...).
His model makes a lot of sense but what remains unclear to me is the following:
At any given time our brain is processing a lot of inputs: external inputs from our various senses and internal inputs. We clearly do not feel conscious of them all. Cerrtainly, we do not feel conscious of many of them "simultaneously". Dennett seems however to say that whenever an object of our phenomenology is discriminated by our brain, it is "conscious".
On another hand he alludes to the notion of probing. Probing that would determine what is reported as conscious. He seems to make a difference between what is conscious and what we report as conscious experience when asked (i.e. probed) to report.
What I don't get is what he exactly means by his notion of "probing". I get it only partialy. I get it when by probing he means triggering a report from the conscious subject: e.g. asking the guy what he sees/feel. However, we are not constantly being asked to report on our internal states and we feel nevertheless conscious in these apparently "non-probed" times.
Of course, I suspect that his notion of what the probing is is more subtle than that. I suppose that internal inputs and external inputs can themeselves serve as "probes".
Maybe this notion is better explained in the rest of the book.
Once very important phrase he wrote is "The multiple draft model makes"writing it down" in memory criterial for consciousness".
I fully agree with the fact that writing something down in memory is critical for consciousness!
I have my own partial theory on consciousness and I should maybe explain it here before to continue Dennett's book. In view of the bold sentence above, I suspect that his views and mine overlap largly.
Sunday, 27 February 2011
The Stanley Milgram Experiment: Obedience to Authority
This is yet another classical psychology experiment. It shows how far most poeple are ready to go when they are in a situation where authority exists. They feel easily relieved of their moral responsability and become able to perform the worst acts.
Friday, 25 February 2011
The Standford Prison Experiment
For those of you who haven't seen this video yet, it is a must see to get an glimpse at the dark side of our human nature.
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