Hello, all, from Bill Powers
This is aimed mainly at our neuroscience contingent, but everyone might have something to say about it. I woke up this morning after a long struggle with a program had been ruining my sleep for some days. Yesterday I spent a few hours basically doing the same thing over and over and not getting anywhere with it. What awoke me was wondering whether every time I went through the same pointless repetition, I was actually starting a new instance of the same program to run in hy head concurrently with all the previous instances. You know how it is: you can start a program like Word and use it for a while, then for some reason leave it running, perhaps minimized, and start the same program again. Now there are two copies of the Word program in working memory, running quite independently of each other except when they have to wait for a resource to become available because the other instance or some other process is using it. I'm talking now about a process in my brain that was trying to deal with some problem in a computer program by running some brain sort of program, not the same sort that runs in PCs. I'll call brain programs "processes."
Strange thoughts, but you know me by now: speak the unspeakable, think the unthinkable, eff the ineffable.
Starting from there I wondered idly (and sleepily) what would happen if we accidentally reorganized ourselves so some higher-level-type process, as part of its operation, started a new instance or copy of itself running every time it got to a particular point. Of course that copy would do the same thing, and soon the brain would be saturated by attempts to run an infinite number of instances of the same process at the same time. Could that be how an obsessive-compulsive disorder arises? Through the process mathematicians call recursion? Or analogous to a self-replicating virus?
That then led in an unexpected direction. I noticed that this sort of problem can happen even in a perfectly-functioning brain. It's a software bug, not a hardware failure. That suggests a whole class of software malfunctions that can happen in a brain in which all the neurotransmitters and synapses and ion pumps and metabolic functions are working exactly normally. In fact, a software problem of this kind can put a strain on resources and actually cause mechanical problems at the level of brain functions. For example, consider the hardware problems that would arise if a new line of reasoning led the brain to use the appendages to reorganize itself with a bullet.
That soon led to considering the sorts of things that could be called hardware processes, and to see in a jolt of insightness (def: a feeling of having had an insight, whether or not an insight has actually happened) that practically everything we study about behavior and other brain-driven activity is the result of processes running in a brain, processes that have almost nothing to do with what the brain actually, physically, does.
Suppose you decide to figure out how a computer works. You take the motherboard out of the case, power it up, and start probing all those little solder joints where the integrated circuits are mounted on the printed circuit board. You keep careful track of inputs and outputs, recording what happens to outputs when you experimentally change one or more inputs. Do you think you would ever discover that the computer is running a program for taking the square roots of numbers entered from a keyboard? Or that the program is ELIZA (or Warren's student's version), or one of my demo programs, or is converting centigrade temperatures to Fahrenheit? Fat chance.
What you will discover by detailed examination of the computer is a population of standardized components like transistors, resistors, capacitors, inductors, diodes, and signal paths connecting the output of some components to the inputs of others. With a full complement of such components, together with reference books listing their measured characteristics, you could then design circuits to do practically anything. And going further, once you had one such design, you could probably duplicate its function using vacuum tubes or field-effect or bipolar transistors. Form and function are nearly independent of each other when it comes to signal-handling circuits.
Without implying that the brain is a digital computer, we can still see that there are levels of organization in the brain at which certain primitive operations are carried out, and other levels where those operations are combined to do things that are quite different from the primitive operations. In PCT we can name quite a few of those different operations, such as perception, comparison, and action. Comparison, for example, requires a component with two inputs and one output. One input has to be subtracted from the other, so one must be excitatory and the other inhibitory. The output carries whatever excitation isn't cancelled by inhibition. It doesn't matter much what the neurotransmitters are, except for the excitatory-inhibitory distinction.
From all this a picture started to form. What if the brain is basically a set of general-purpose components, starting out with almost no organization built in, except for a small assortment of control systems that control a few basic variables like amount of food in the mouth? A speculation suggested by available data is that everything starts out pretty much connected to everything else at least a little bit, with organization appearing by pruning out connections that do nothing or are counterproductive. We understand pretty well how that can come about through random reorganizations and selective retention.
Of course the range of circuits that can be built from a given kit of components is limited by the basic properties of the components. You can't built a microwave amplifier from audio-frequency transistors. The brain has evolved into regions and layers, each one presumably best suited by its properties for some class of circuitry, though it doesn't start out equipped with many examples of any class.
The circuitry is built mostly during the lifetime of the organism, and the building is guided from the top down, not the bottom up. Don Campbell called this "top-down determinism." Which brings me to Jill Taylor and her TED talk.
http://www.ted.com/talks/jill_bolte_taylor_s_powerful_stroke_of_insight.html
Somewhere around 18 minutes into the talk, Jill explains that we as human beings are "the life force of the universe with manual dexterity." I call this life force the Observer Self, the core of what I have proposed to be a "reorganizing system" that enables the construction of whatever control systems are needed to develop and support the life support systems (among other purposes). The blueprint for that reorganizing system is basically all that needs to be transmitted down the generations, along with suitable assortments of components arranged for easy reorganization into functioning circuits. It takes only a few billion years for such a kit to be acquired. There's been plenty of time for the current universe to be full of examples of such kits.
I think this picture has many ramifications. You can go through the tenets of almost any branch or school of psychology and find a fit with only a little reinterpretation. The blind men and the elephant again. Everybody got it wrong, but not totally wrong. At least we have been paying attention to some of the right things.
Not much really new in all this, except to me.
Best,
Bill P.
The point of the social network analogy is to try to convey how completely in the dark neurons really are, and thus that they have no recourse except to learn to "trust" the signals they get from others (and yes this is just synaptic weights). People tend to project themselves into everything, and so implicitly assume that neurons can "see" and "talk" just like us -- this leads to very incorrect fundamental assumptions about how they can function in certain cases.