Consciousness, in mice and men and flatworms

Deutsch: Phrenologie
Deutsch: Phrenologie (Photo credit: Wikipedia)

Of all emergent phenomena consciousness is the most mysterious, probably because we don’t seem to have a handle on the concept. We don’t understand how it arises and probably not much about what it comprises and how it works. We know that it, apparently, can be switched on and off, as when we go to sleep or are sedated or knocked out by some accident or other.

It is only marginally under our control. In general terms we can be conscious or awake, but not conscious of anything specific. We can be in a reverie or day dream, or we can be doing something semi-automatically, like driving. But we can “snap to” and be conscious of something specific, as when some event happens while driving that needs our full attention. Or the door bell snaps us out of our reverie, or we notice a cloud that looks like a dog, or cat, or, more likely, a sheep!

English: We're following the leader! What caus...
English: We’re following the leader! What caused the car in front to brake? Was it a horse and rider? Was it someone coming off the public footpath on the brow of the hill? That’s the pleasure of nose-to-tail driving on the A158. It just keeps your brain alert all the time! (Photo credit: Wikipedia)

Even when we are fully awake and concentrating on the idiot who just pulled out in front of us, we perform actions of which we are not fully aware, such as change down a gear or put on the brakes. We are aware of these actions to some extent as they are not fully automatic, like the movement of our legs when we walk, but we don’t have to think about which pedal to press or how to move the gear lever to change gear, as we did when we were learning to drive.

Washoe
Washoe (Photo credit: Wikipedia)

I might have said before, in a previous post, that I don’t think that it is feasible that consciousness is only found in mankind. Chimpanzees share 98.8% of our genes, so it reasonable that they share many of our abilities and they can certainly use tools and reason. It is unlikely that consciousness is an expression of something in the 1.2% of the genes that are unique to humans. Chimpanzees show fear and happiness , they sulk, they get angry and show other emotions. While the expression of emotions doesn’t prove that they are conscious, I find it hard to imagine a conscious entity would not express its consciousness through emotions, and that a non-conscious entity would show any emotions.

Computer mouse
Computer mouse (Photo credit: Pockafwye)

If chimpanzees are conscious animals as we are, then it follows that other animals are conscious entities to some extent or other. Some people believe that it has been demonstrated that most animals have consciousness, but I consider to be very likely, but not yet proved. Even a mouse, a “Wee, sleekit, cow’rin, tim’rous beastie” as Robert Burns put it, demonstrates its fear, and with its own species, anger. It is unlikely that a mouse is *as* aware as a human or even a chimpanzee, and it would be very difficult to find self consciousness in a flatworm though.

English: The planarian Schmidtea mediterranea
English: The planarian Schmidtea mediterranea (Photo credit: Wikipedia)

But then again, consciousness is related to mind and to the brain, and the brain is the major part of the “Central Nervous System” in mammals. It is possible that the more complicated a brain the more consciousness a animal possesses. Even a flatworm possesses a very simple brain-like structure called a ganglion. So, maybe, a flatworm posses a spark of consciousness, an atom of awareness of the most rudimentary sort.

English: Main regions of the vertebrate brain,...
English: Main regions of the vertebrate brain, shown for a shark and a human brain (the human brain is sliced along the midline). The two brains are not on the same scale. (Photo credit: Wikipedia)

Or there may be some threshold below which consciousness is impossible. A simple eyespot, such as flatworms possess cannot form an image. To form an image a much more complicated eye structure is required, so there must some limit of animal complexity at which vision can be said to be possible. A fuzzy limit, maybe, but a limit nevertheless.

If consciousness is truly an emergent phenomenon of the brain, the what properties of the brain could enable consciousness? Just as the chemical and electrical properties of water molecules are what enable the emergent property of wetness, some features of the brain and its shadow partner, the mind, must lead in some way to the phenomenon of consciousness.

English: Two water molecules
English: Two water molecules (Photo credit: Wikipedia)

The most obvious characteristic of the brain that really differentiates the brain from other organs is the concentration of neurons, billions of them, each connected to thousands of others by synapses. The number of connections is immense, but sheer complexity in itself does not imply consciousness.

In the case of emergent phenomena in general, it seems to me that it is easier to work from the top down as it were, the macro and consider what micro properties could feasibly cause the phenomenon. If we look at the wetness of water and consider that water is made up of molecules with physical, chemical and electrical characteristics we can at least speculate that the wetness of water is at least partly caused by the way that the molecules stick to and move across other molecules in a surface such as the skin. The water molecules are able to stick and let go and move over other molecules in a way that wets a surface, and forms a concave meniscus in a tube in a characteristic way.

English: Pendle Water, Nelson, Lancashire At t...
English: Pendle Water, Nelson, Lancashire At the South end of Victoria Park, Pendle Water flows out of the park, for a couple of miles to join the Lancashire Calder, which after a few miles westward, itself will flow into the River Ribble and hence to Preston and the Irish Sea and the Atlantic Ocean. Who knows where the water molecules that we see here passing in December 2008 will have got to by now? (Photo credit: Wikipedia)

In  comparison mercury atoms have different electrical chemical and physical characteristics. They don’t form molecules in the same way, and while they slide over one another, they don’t stick to other molecules and let go in the way that water molecules do. Consequently mercury atoms don’t wet surfaces like water molecules do and a mercury meniscus is convex not concave.

Close-up of a mercury-filled maximum thermomet...
Close-up of a mercury-filled maximum thermometer. The break in the column of mercury is visible. (Photo credit: Wikipedia)

So, we can work out, in rough terms, why water is wet, by comparing water and mercury, and noting their micro-properties. Can we achieve the same with the phenomenon of consciousness? Well, the brain is a computation engine of sorts, and so maybe we can compare it to a computer. Computers are not (yet) conscious and brains contain minds which are conscious. Can we make any guesses based on that?

Babbage difference engine
Babbage difference engine (Photo credit: tolomea)

You can probably tell from the questioning way that I am discussing this topic that I don’t have any firm opinions on the matter. There are a couple of differences that I will point out though.

Computers are highly organised and computational functions and memory functions are completely separate, physically and computationally. A computer is also clock driven, with each operation taking up exactly the same number of “clock ticks” each time it is performed. In contrast, while a brain does have areas in which functions seem to reside, and a particular area may “light up” every time one raises a finger for example, memory seems to be more diffuse in its location, as compared to a computer.

English: Thalamus. Part of the brain. MRI image.
English: Thalamus. Part of the brain. MRI image. (Photo credit: Wikipedia)

Secondly, a brain’s “architecture” changes over time, whereas a computer’s does not. A brain may make new connections (which may have something to do with memory), while a computer stays as it was when built.

Thirdly, a brain is enormously more complex than any computer yet built, at least in terms of the number of interconnections in it and its ability to re-wire itself with new connections.

Synaptical transmission (chemical). A: Neuron ...
Synaptical transmission (chemical). A: Neuron (Presynaptic) B: Neuron (Postsynaptic) Mitochondria Synaptic vesicle full of neurotransmitter Autoreceptor Synaptic cleft Neurotransmitter receptor Calcium Channel Fused vesicle releasing neurotransmitter Neurotransmitter re-uptake pump (Photo credit: Wikipedia)

I don’t know if these differences are significant in terms of explaining the problem of consciousness. I suspect that they are at the root of the problem, but I could be totally wrong. It may be the “programs” that run in the brain and computer that make the difference, but that just moves the issue to another arena.

And I’ve run out of space. I could touch on the “android” question, but I’ll leave that for now.

English: This is a photograph of EveR-2, a fem...
English: This is a photograph of EveR-2, a female android developed by the Korea Institute of Industrial Technology and demonstrated to the public in October 2006. It is 165cm tall and weighs 60kg. (Photo credit: Wikipedia)
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