03/03/2010 by admin.

There is an interesting post by J. Lehrer in Frontal Cortex (here). He examines the metaphor of consciousness being the result of a ‘vote’.

Like Crick and Koch, I believe our head holds a raucous parliament of cells that endlessly debate what sensations and feelings should become conscious. These neurons are distributed all across the brain, and their firing unfolds over time. This means that we are not a place: we are a process. As the influential philosopher Daniel Dennett wrote, our mind is made up “of multiple channels in which specialist circuits try, in parallel pandemoniums, to do their various things, creating Multiple Drafts as they go.” What we call reality is merely the final draft. (Of course, the very next moment requires a whole new manuscript.)

And yet, and yet…There is the problem of the election. If this blink of conscious perception is a vote, then where is the voter? We can disguise the mystery with euphemisms (top-down attention, executive control, etc.) but the mystery still exists, as mysterious as ever. We deny the ghost, but still rely on models, metaphors and analogies in which the ghost controls the machine.

The problem as I see it is that the mechanism of the election is not the right metaphor. If things are visualized in a sequential way, it is difficult to lose the ghost. First we imagine two areas of neurons and that they are organized in similar maps, like the map of the retina in the thalamus and the one or more maps of the retina in the cortex and enlarge the number of maps to cover all the things that might be in the content of consciousness. This we suspect exists. Then we imagine that the neurons in one area communicate with those with similar map positions in the other area, and vice versa, to give feedback loops. This also we suspect to exist between the thalamus and the cortex and between separate areas of the cortex. And further we imagine that these parallel loops between two versions of the same map type are a bit sloppy so that there is a good deal of overlap. Now we have a massive set of parallel overlapping feedback loops. This resembles, not a digital computer, but an enormous analogue computer. When the input to such a network changes, there would be a short period of instability and then it would settle down to a stable state. This would be the ‘best fit scenario’, ‘the lowest energy configuration’, the ‘consistent perception’, etc. As a general idea, this could be thought of as an ‘election’ without the need for ‘voters’.

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01/03/2010 by admin.

This bit of baggage is the idea of the ‘tabula rasa’ or the blank slate which originated with John Locke in the late 1600s.

Let us then suppose the mind to be, as we say, white paper void of all characters, without any ideas. How comes it to be furnished? Whence comes it by that vast store which the busy and boundless fancy of man has painted on it with an almost endless variety? Whence has it all the materials of reason and knowledge? To this I answer, in one word, from EXPERIENCE.

This lack of human nature or of inherited mental abilities was a good argument against tyranny, bigotry, racism, sexism, slavery etc. because we were all born with equally empty brains. Only force, exploitation and bad luck can make us unequal. For a long time, behind ideas of politics, education, morality and so on, has been the assumption that the newborn brain is without structure. Of course we can still have these good things without the theory of tabula rasa. If it is actually not a correct theory we can abandon it, and still get on with democracy, universal education and other aspects of equality in our societies.

The continual return to the ‘nature verses nurture’ argument is the attempt to advance or eliminate the tabula rasa philosophy. However, the argument has already been settled.

1. Nature is important. The brain is born with an enormous amount of structure and with learning programs in place. We have some instincts is well. There is a ‘human nature’ and a long list of activities and beliefs that are found in all societies.

2. Nurture is important. Almost everything we do or think is affected by our memories. We learn through experience. The environment makes lasting changes to our brains. All those remembered facts and skills that make us unique come from experience.

3. Nature and nurture cannot be separated. It is silly to say that some mental ability is x% inherited and 1-x% acquired. Everything is an inseparable mixture of the two working together. Nothing happens due to genetics; nothing happens due to environment; everything happens due to the interaction of genetics and environment.

Alison Gopnik says:

The brain is highly structured, but it is also extremely flexible. It’s not a blank slate, but it isn’t written in stone either.

What effect does the denial of in-born structure in the brain have on the subject of consciousness? The biggest problem is about the relationship between language and consciousness. Of course, we are unsure of the detailed relationship. But trying to understand the relationship may be treated as more than a straight forward scientific question and instead treated as a political or sociological one.

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