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Re-Entrant Mapping and Consciousness

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As I was never satisfied with Objectivism's explanation of consciousness and free will, I've been looking at a bunch of alternative explanations. One that I've found quite intriguing is re-entrant mapping as an explanation for consciousness and the perception of free will. Re-entrant mapping is the existence of neurons that function as observers of other neurons firing. Essentially, these neurons just watch other neurons work and are responsible for the perception of self-awareness - so the theory goes. If you pick up the most recent issue of The Economist, there is a "Survey of the Brain" that I think is really interesting. I can't recall everything in the article, but one interesting observation is that awareness of our own actions (like moving a finger) occurs something like 3 mili-seconds after the brain tells the finger to move, which has pretty far-reaching implications. Anyways, I'm clearly not an expert on this, but try and pick up a copy and read it, I'd be interested in your thoughts.

Edited by NewYorkRoark
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I don't know what you mean by "Objectivism's explanation of consciousness and free will", so I don't know what an alternative explanation would be. In what way do you consider "re-entrant mapping" to be an alternative explanation? Of course I have questions about this theory, e.g. what does it mean for a neuron to "watch" another neuron (and doesn't the concept "watch" presuppose "consciousness")?

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One that I've found quite intriguing is re-entrant mapping as an explanation for consciousness and the perception of free will. Re-entrant mapping is the existence of neurons that function as observers of other neurons firing. Essentially, these neurons just watch other neurons work and are responsible for the perception of self-awareness - so the theory goes.

Bah! there's a theory for this? Thanks for the name, now I can look up researches on the subject.

I can't recall everything in the article, but one interesting observation is that awareness of our own actions (like moving a finger) occurs something like 3 mili-seconds after the brain tells the finger to move, which has pretty far-reaching implications.

It makes sense that the awareness of the change of location of the finger would occur after it has happened: it takes time for the sensors in the muscles and tendons to transmit back to the brain the information about the change of tenssion, and it also takes time for the eyes to transmit the information to the brain as well.

Though it seems logical that planning a movement consciously will somehow shorten the delay between the time the change of location happened and the knowledge that it has (because this happens during movement that is mediated by the cerebellum).

As for the meaning of neurons that "watch over" other neurons... it doesn't imply that they have consciousness: it's metaphor that means that those "watcher neurons" are getting their input from these neurons that encode concepts. Now before you jump all over me, as far as I know it has not been observed yet that certain neurons encode concepts, but I think that there must be such neurons. And then there also much be neurons connected to those neurons that encode principles. I view the brain as a pyramid that starts from the senses and converges to build more and more big and abstract concepts and principles. And those neurons that encode principles and concepts are (so I speculate) connected to a system that analyzes the patterns of activation, while taking under account the meaning of each neuron (what it encodes and what is the meaning of different patterns of activity).

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  • 4 weeks later...
As for the meaning of neurons that "watch over" other neurons... it doesn't imply that they have consciousness: it's metaphor that means that those "watcher neurons" are getting their input from these neurons that encode concepts. Now before you jump all over me, as far as I know it has not been observed yet that certain neurons encode concepts, but I think that there must be such neurons. And then there also much be neurons connected to those neurons that encode principles. I view the brain as a pyramid that starts from the senses and converges to build more and more big and abstract concepts and principles. And those neurons that encode principles and concepts are (so I speculate) connected to a system that analyzes the patterns of activation, while taking under account the meaning of each neuron (what it encodes and what is the meaning of different patterns of activity).

You seem to be describing a bottom-up kind of awareness. But, what's the use of the top of the pyramid? That is, does the thing that calls itself 'I' and 'me' still have a function? I can't imagine it does, in your pyramid. I mean, if all the forming and analyzing of concepts and principles is done by neurons, that doesn't leave 'me' much to think about, does it?

If my meager knowledge of objectivism serves me right, awareness should be thought of as a top-down kind of thing. The top does the thinking and deciding, the lower levels do the encoding and transmitting, resulting in actions.

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You seem to be describing a bottom-up kind of awareness. But, what's the use of the top of the pyramid? That is, does the thing that calls itself 'I' and 'me' still have a function? I can't imagine it does, in your pyramid. I mean, if all the forming and analyzing of concepts and principles is done by neurons, that doesn't leave 'me' much to think about, does it?

Ahh, well... I don't understand what you are asking. To me it sounds confused. I did not say that any activity of "higher level" mental functions has to be initiated by an activity of neurons that encode lower level functions (coming from the senses).

How is "awareness" determined?

It's called psychophysics, it's a science that deals with the relation between a stimuli and a subjective sensation reported by the patient.

You can also learn about a relation between certain brain region (or 1-6 neurons) and a conscious mental experience during open brain surgery, or by recording cell activity in reponse to various stimuli from animals (like a fly).

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It's called psychophysics, it's a science that deals with the relation between a stimuli and a subjective sensation reported by the patient.
I'm aware of the discipline. My question is, what concretely are the physical correlates of "awareness", such that those properties exclusively identify that a person "is aware", and does not have another mental state. What are the scientific tests that tell you that a person is "aware that X", for such a range of propositions as "moved one's own leg", "has been stabbed", "saw a car", "heard the first four notes of 'Kurdaneh'", or "proved Fermat's Last Theorem"? I'm looking for specialized knowledge -- I thought you were a brain scientist.
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My question is, what concretely are the physical correlates of "awareness", such that those properties exclusively identify that a person "is aware", and does not have another mental state. What are the scientific tests that tell you that a person is "aware that X", for such a range of propositions as "moved one's own leg", "has been stabbed", "saw a car", "heard the first four notes of 'Kurdaneh'", or "proved Fermat's Last Theorem"? I'm looking for specialized knowledge -- I thought you were a brain scientist.

I'm not a brain scientist, and I never said I am. I don't appreciate the tone.

It is not possible to open someone's brain, look at a certain pattern of activity and determine "oh yeah, this person is currently thinking about how much he feels like having strawberry flavored ice cream".

I guess that sometime in the future it should be possible, I don't know for sure.

The brain contains neurons that are involved in non-conscious activities and also neurons that are involved in an aware activity, or conscious mental activity. As far as I know, nobody knows what physical properties distinguish between a neuron that is associated with an aware mental experience and one that simply processes information without awareness. It can only be known based on the location of the neuron in the brain, or as a result of stimulating the neuron and asking the patient to report his sensation.

On a larger scale, scientists do know that activity in the visual cortex must involve some perception of a visual image, and not with thinking about the flavor of strawberry ice cream. Likewise if you touch a person's leg you are not going to see activity in the auditory cortex, but in the region that deals with sensations of the leg.

In some areas, more can be known about the mental experience by knowing the activation patterns of neurons, because it has been studied and recorded that the neurons on a certain location are responsible for X, and fire in correlation with Y. So the location and firing rate can tell you that the person is aware of X. For example: the visual cortex is organized like a matrix, where each region is responsible for handling visual stimuli from a certain location in space. So if you record activation on location X you know that the animal is experiencing some visual image in location Y in space.

There, hope it answers your question. If not, try explaining your question further.

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I'm not a brain scientist, and I never said I am. I don't appreciate the tone.
I don't care what your problems with tone are. I thought you were in some brain-science related area, but perhaps I had you confused with some one else. That would explain the quality of your answers when it comes to this topic. My mistake.
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I don't care what your problems with tone are. I thought you were in some brain-science related area, but perhaps I had you confused with some one else. That would explain the quality of your answers when it comes to this topic. My mistake.

You have perfect knowledge of what I do. You know I am not a brain scientist. Therefor to call me by that title is an attempt to ridicule.

I put effort and time into my post and answering your question. If you have problem with the quality of the answer you can at least be polite and point out the problems in it instead of telling me that it generally sucks.

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Ahh, well... I don't understand what you are asking. To me it sounds confused. I did not say that any activity of "higher level" mental functions has to be initiated by an activity of neurons that encode lower level functions (coming from the senses).

Then how do you suppose higher level mental functions would function? You said you think there're neurons that encode concepts, and also ones that encode for principles. How do the higher level mental functions fit in the big picture?

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