Here is a brief description of a topic that I have been thinking about, on and off, since the
1980s.
Before the early 1980s my own theory of consciousness was that there is a different ‘Seat of Consciousness’ for each of the senses. After all,
we seem to taste on our tongues, smell in our noses and feel on our skin. This idea was not entirely satisfactory because:
- There does not appear to be a structure, in any of these organs, which could be the ‘Seat of Consciousness’.
- As we hear with both ears, sounds appear to come from a particular direction - outside the body.
- As we have binocular vision we experience objects outside the body, and a ‘Seat of Consciousness’ outside the body does not seem
possible
Then something happened, that gave me an idea, which seemed to explain everything. My youngest son, Marc, made friends with an elderly couple, John
and Vi. John had to go into hospital for heart surgery, and while recovering was put on very strong painkillers. These caused him to hallucinate. On one occasion he saw an armchair as a
baby elephant. Nothing spectacular like a pink elephant, just a grey armchair appeared to him as a grey baby elephant. Everyone else saw it as an
armchair so the probability was that, in the ‘real world’, it was an armchair. Where could John’s experience of it have been changed to an elephant?
- In the eyes? Unlikely. Both eyes would have to be implicated. Eyeballs are purely ‘mechanical’ in forming an image on the
retina.
- In the optic nerves? Unlikely. Although some processing may take place in the optic nerves, both optic nerves would have to be implicated
- In the brain? The only place left. Most likely.
An answer came to me in a flash of inspiration, almost in its entirety.
WE EXPERIENCE REALITY, not directly in the ‘real world' but, IN A MODEL OF THE WORLD THAT EACH OF US HAS CONSTRUCTED INSIDE HIS OR HER HEAD.
The Model
I call this inner world ‘the Model’. When we see, hear, touch, taste or smell something we do not do so directly. We experience it within the
Model. We experience the Model’s representation of it.
At first, I was rather shocked by the idea but the more I thought about it, the more all the pieces seemed to fit.
Some attributes of the Model:
- A representation of the outside world is part of the Model.
- The Model is dynamic in both time (Memory, perception of motion) and space. When you are in a small room the Model only seems to extend to the limits
of that room. When you gaze at the stars in a clear night sky the Model seems to extend almost to infinity.
- The Model is continually being updated or modified from our senses - external modification. In John’s case the painkillers had interfered with
the process that updated his Model so that he saw the armchair as an elephant.
- A representation of the body is part of the Model. This explains the ‘Seat of Consciousness’ scenario. We taste things on our tongues
etc. because a representation of the body is part of the Model. We see things as being outside the body because a representation of the outside world is part of the Model.
- The Model is also modified by memory, thought, reason, belief, imagination and emotion, which are functions of the brain and are also represented in
the Model - internal or self-modification.
- During development, in infancy, awareness of the world in general comes before awareness of the body in particular. Awareness of the body comes
before self-awareness. What I call self-awareness occurs when the ‘mind’ (the self, the id) is incorporated into the Model. This incorporation is the result of observation,
memory, thought and reason, and in most people happens as a natural part of development. In that sense, the mind is an ‘invention of the Model’ which becomes part of the
Model.
- The older we get the more we have invested in our Models. We trust them and rely on them utterly. This explains resistance to new ideas, especially
among the older generation. (Of which I now find myself to be a member)
- Where exactly are the components of the Model? Are they in specific areas of the brain such as the visual cortex, or are some of them distributed
generally across the brain? This is an area for further research.
I believe that all other vertebrates and some invertebrates have a Model, although not as sophisticated as ours. I will discuss invertebrates
including social insects at another time.
I believe that a thinking machine or a robot that is to be capable of navigating the real world needs to incorporate a version of the Model in order to be
successful.
Sometimes, when you here of an idea, or theory, you know instinctively that it is right. Examples, in my lifetime, include the role of DNA and RNA in heredity and cell function, and Plate
Tectonics. I have the same feeling about the Model.
Mike Holden - Jan 2010
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