Your Mental Radar

Very little is known about the precise way our minds function. There is even considerable objection to the use of the word "mind" because it implies something existing at a higher level than the sum of its parts. In its common-language usage, however, the term gives us a convenient handle, but we must not imagine that a mind is a thing.

A convenient way to instruct about what happens in mental activities is to employ an analogy. Assuming that the mind contains some sort of complex radar is obviously risky, yet there must be a mechanism slightly comparable to radar (plus a lot of other things).

In the brain alone, there are billions of neurons; each neuron consists of an extremely long and thin, wire-like, complex strand, and a bulky cell body near one end [see part (A) of Fig. 10 on page 75] which has the function of maintaining the long fiber and, if necessary, in the case of neurons outside the brain, organizing a replacement (regeneration) if the distant part of the fiber dies, due to accident.

The neurons are not piled or jammed into the brain and spinal cord helter-skelter. They are highly organized into layers and bands of vary­ing kinds and functions. In the growth of a human embryo, the basic neural cells arrange themselves in the foundations later to become brain and spinal cord. As the foetus grows larger, the cells send out the processes or fibers which ultimately run to specific areas of the body. For some time, the cells are too underdeveloped to carry messages. But long before birth many of them are mature enough. When only an inch long, the foetus will respond to tickling with a hairy bristle. As time goes on, more and more neurons mature. Eventually, the neurons are fully developed and carry on their complicated functions of adjusting the child to its surroundings in a way that insures personal survival. Most of the elemental acts of life are built into the infant, requiring no learning: the motions of muscles of the intestine, reflexes for breathing, and other motions of the parts of the body essential to survival. How far instincts or built-in behavior extend into later life is not clear. We will omit reference to instincts in humans.

But most of the neurons are not fixed in their connections. A huge number, in fact, make connections with several others through brush-like hairs. There is not a full contact, actually, but the hair-like processes of two neurons come together in a tiny area-of-nearness (synapse, Fig. 10.) // is these areas-of-nearness that are so important in the control of one's behavior and in learning. It is here that something happens to permit a message to jump over, or deny it permission to pass. That "something" we can more or less "train." In some way, the threshold which would pre­vent the continuation of the impulse across the synapse has to be lowered if the message is to go through.

As time goes on, the aimless motions become gradually narrowed down by higher controls until the muscles work more and more in harmony and on call. How this happens is not understood. It would seem as if a volun­tary decision were made not to move muscles aimlessly. But there is grow­ing evidence to lead us to think the decisions themselves are not made voluntarily but rather as a result of other impulses coming into the picture, either from outside the body by way of the sense organs that relate us to the outside world, or from within. These other impulses check a message coming in, apparently by pre-set conditions, and allow it to continue (or stop it) according to previous experience plus the particular situation of the moment. In other words, the system as a whole is neither entirely automatic (as it appears to be in insects, where instincts are all-powerful, with built-in reflexes, and the neurons are inflexibly joined in more-or-less predetermined patterns), nor entirely subject to free choice. This flexi­bility of some choice found in man and other higher animals permits a certain modification of behavior.

This freedom of some choice is the basis of our tremendous capacity to learn. We could, by changing the conditions in the millions of areas-of-nearness, redirect the impulses that come in to go to any one of dozens of millions of alternate pathways, depending upon the situation of the moment.

Learning can thus be defined, in its simplest sense, as the directing of impulses into pathways that accomplish muscle motions (or secretions) leading to (1) survival of the person. (2) cooperative activities with others, and (3) higher mental activities called thought and reflection. In thought and reflection, the muscle motions seem to be sub-threshold motions of the tongue muscles, not quite expressed as motion.

By this means, over a long period of time, the individual reacts to what goes on around and inside him, step by step, lesson by lesson, growing, changing, profiting by past experience and making more and more re­fined or selective motions accordingly. The decision as to what is or is not rewarding is made on the basis of past reinforcements that gave pleasure and avoided pain.

If one wishes to control the learning process, he pre-sets the little flags beforehand, and that is part of studying. In a simple case, we might pre-set a flag with the symbol for water, H2O, and connect it with certain pathways leading to the name "water" and then to the properties of water — its wetness, density, and any number of things, including how it reacts with other compounds. The pre-set flag now awaits the scanning of the radar with its template of that symbol.

Presently, in an exam, the symbol H2O is picked up by the visual sense. It comes in, is perceived, and placed on the radar template. The radar begins to scan, and when it comes around to the flag bearing H2O, it trips the trigger, and the pre-set pathways to the properties, etc., are auto­matically followed out. This is a great over-simplification of the many checks and counter-checks which actually exist, but it will serve to assist in interpreting the do's and don'ts of studying.

Let us take another example: By observation, you note that the gas gauge on your car reads "nearly empty." You pre-set a flag bearing a re­semblance to a service station. You push this to the back of your mind, and continue driving, conversing and paying no further attention to the gasoline situation. After a few miles, a gas station appears in the distance. The picture of the station, as with all views appearing on the ever-chang­ing radar templates of pictures continuously pouring in, with its pumps and brand signs, is perceived, placed on the radar template, and the radar then sweeps over the surface of your mind. Upon matching up with the flag you pre-set, the trigger is tripped, and a message goes along the wires (neurons) until it arrives at the memo to get the tank filled.

To recall means to cause to return to one's attention the name of some­thing or the many things connected with the name of something. To recognize means to perceive the identity of something previously known, when confronted with it. In essay exams, recall is demanded almost all the way. In objective exams of the simpler types, recognition is asked for. In other words, in an essay exam, you are given a few words or sentences and invited to call forth in an organized way what you know of these things. In a simple objective exam, you are asked to check the identity (or lack of identity) of some word or other symbol. In a complex objective exam, you must rearrange what you know, from clues, to be able to recognize the right answer. This rearrangement process is thinking.