GABlog

July 11, 2014

Thought Experiment

Filed under: GA — Q @ 6:45 pm

First, imagine a computer which includes complete monitoring of every internal electro-magnetic event, the transistors and memory and so on. We can see the physical arrangement and what happens in the circuits, and, initially, we can compare it to what is shown on the screen. Our task is to predict what is being shown on the computer screen simply on the basis of the computer’s internal activity. The idea here is that we can see all the switches going on and off, the ones and zeros, and we have to find the code to translate that activity into what is visible to the user. I would guess that this would be a fairly easy task for someone with the right skills. One would start by figuring out the basic ASCII computer code and then working up to the higher level codes.

Now imagine that we could somehow monitor every electro-chemical action of the human brain at any one moment and over time. The latest issue of MIT Technology Review (July/August 2014) describes some remarkable advances along this line. A new technique calls “optogenetics” provides a much more detailed view of cell activity than the fMRI. We’re still far from a complete picture, of course, and I doubt that it’s even possible to provide a complete picture of all significant brain activity in time. This is a thought experiment. Note that initially we also have access to everything the person reports is going in their consciousness. So, for example, when he or she remembers a particular event, we could compare the reported memory with the specific brain activity. Our problem then would be to try to figure out what was going on in the person’s consciousness from observing the neuro-chemical action of the brain alone.

First of all, we should note that comparing brain activity to what the person is doing, their health, and so on, would be enormously helpful for doctors trying to find cures, especially for mental health or brain-centered health problems like autism. Existing brain research, neuromania aside, has already generated valuable medical results.

But the larger question is whether we would be able to reach the point where we would be able to look at the brain activity by itself and say exactly what the person is thinking or feeling or doing. Would we be able to actually predict what the person is going to do next?

David Talbot reports on some experiments by Gabriel Kreiman which suggest that brain activity in key areas of the brain actually precede conscious decisions by “anywhere from hundreds of milliseconds to several seconds” (“Searching for the ‘Free Will’ Neuron” in MIT Technology Review July/August 2014: p.65). These results allow scientists to claim that brain events actually cause so-called “free will” choices. We should note, however, that the test results rely on the time difference between when the subject presses a button and when particular neurons “related to decision-making” fire. There is the problem that an electrical impulse from brain to finger takes time, time which might account for the supposed lag between brain activity and conscious decision. There is also the problem of identifying which particular neurons actually “cause” a decision.

Going back to our thought experiment, I assume that we would be able to learn a lot from knowing the correlation between brain activity in specific areas and conscious thoughts and feelings and perception. First of all, we could nail down specifically which parts of the brain are responsible for exactly which functions. We would be able to correlate certain patterns of brain activity with specific emotions and memories and perhaps even ideas. Eventually we would be able to predict, purely on the basis of recorded brain activity, what the person is feeling or thinking—but only, I would guess, in a general way, not precisely.

My understanding is that the brain doesn’t operate according to a fixed code like a computer. The brain is, in effect, constantly reprogramming itself. Of course, all inputs from the environment have the effect of reprogramming the brain—a la Pavlov’s dogs, and in much more sophisticated ways. But I would suggest that the brain, in effect, “consciously” and unconsciously programs itself in various ways. There’s what I call an “X-Factor” which would make it impossible to correlate brain activity precisely to the contents of consciousness.

Existing research suggests that everything that happens in consciousness (and unconsciousness for that matter) has correlated brain activity—which is not to say that this correlation operates in any predictable way. The existence of the unconscious, btw, complicates the attempt to sort out cause and effect in decision making and brain activity. It’s not clear that the unconscious operates by any kind of deterministic process. Our dreams, for example, are creative and unpredictable. In sum, I don’t think we can ever break the code that correlates brain activity to consciousness.

In evolutionary terms, consciousness is a way for an organism to negotiate its environment. I think we have to content ourselves with a functional explanation or have recourse to a spiritual one. The function of the brain in terms of the organism as a whole might help explain why we can’t break the brain-code: we have to deal with the unpredictable, and perhaps an unpredictable organ is best capable of doing so.

Finally, it’s not clear that human consciousness is qualitatively different from animal consciousness. We have a peculiar social awareness that makes for conscience and self-consciousness, but this is arguably only an expansion of consciousness to new contents.

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