The Parents' Review

A Monthly Magazine of Home-Training and Culture

The Brain in Relation to Education

In selecting this subject, the Education of Children, I thought I might be of some use to parents by giving a superficial account of the development of the brain. The brain is the organ in which the mind resides, and all mental operations depend on the strength and activity of that living machine. The brain is the most complex part of our anatomy. Its functions are very varied, while the component parts are as numberless as the grains of sand on the seashore. Some think the mind, or the personality, the Ego, as a vague sort of ether, which, though it may clothe us, yet is not a part of us. This may afford debatable material to the speculating metaphysician, but, to us, all things are real and earnest, and we wish to deal with facts and results rather than theories. Briefly stated, all mental action is associated with brain activity. As the brain develops, so does mind. When the brain fails through disease or age, the mind likewise disappears, whilst thought and mind are temporarily extinguished during unconsciousness, whether by sleep or by artificial means. The difficulty in this subject is to know where to begin and where to end. I must therefore give a cursory description of the nervous system, of which the brain is the highest development.

The nervous system is made up of two elements—nerve cells and nerve fibres. The nerve cells are of great variety and shape, and of course their functions are very numerous and different. Some nerve cells receive the sensations of touch or temperature, others of sight or smell, others direct motion, either voluntary or involuntary, while the highest brain cells are psychic or mental, or, we might term them, analytical. The nerve fibres also vary in structure, but they are for the purposes of carrying impulses either to or from the cells. It is important, then, to remember these two factors, nerve cells and nerve fibres.

The nerve cells in the brain form a grey layer about 2/4 to 3/8 inch in thickness, on the surface. In order to afford more room, or a larger superficial area, the brain, instead of being fairly smooth as in birds and lower animals, is in man divided up by wavy indentations, or folds, into what we term 'convolutions.' The outer surface is thus crinkled or folded on itself. Thus, the more it is folded or convoluted, the more area there is for cells and the higher brain development. Imbeciles and idiots in whom the brain does not develop have very few convolutions. The surfaces of their brains have so few clefts or folds that they resemble the brains of dogs or lower apes. These brain cells are in layers, and we can divide the layers by the shapes of the cells. Some of them are triangular, others take oval and varied shapes. The cells are bathed in a clear nourishing fluid, which exudes out of the small blood vessels. We call this fluid 'lymph.' If this fluid be fresh and healthy all goes well. If there be alcohol in the blood, the poisoned lymph produces a variety of nerve force, which is too well understood to require description. But the lymph may get saturated with injurious products as the result of improper feeding. This also modifies the brain cells injuriously—to wit, the irritability of the gouty man.

We thus see the immense importance of a proper life in every sense of the word; and if we truly realize this fact, ought we not to devote our lives to improving those whom we can influence? and first and nearest amongst these are our children.

I have recently been examining the brain of a woman who not only was a hard drinker, dying at the age of thirty-five from that cause, but also her parents had been drinkers, so that her heredity was against her. In this case the outer layer of the brain cells—those which developed last, and we infer are higher in the mental processes—had decayed and disappeared entirely; whilst most of the brain cells showed recent change for the worse, and many were shrunken, having long ceased to partake in any mental function. This poor woman's mind was a complete wreck through alcoholic poisoning.

Alcohol is one of the worst brain poisons. Its action is very subtle, and its ravages creep on gradually but with certainty. It attacks the highest intellectual centres first, impairing judgment and will-power. Next to be affected are movements of the body and speech; while in advanced cases not only every part of the brain is diseased, but also the nerves of the body. Alcohol is never a food, and very seldom a necessity; and this fact ought to be laid hold of by those who train the young. On this account it is wise and right for young people to abstain from alcohol till the age of twenty-five, so that every advantage is given to mental development, and after that period they may be allowed to judge for themselves.

The brain areas.—The surface of the brain is mapped out in areas. As already stated, the outside layer, which we call the cortex, which is the Latin for bark, is made up of layers of cells. This layer is crinkled into wavy folds or convolutions in order to afford a larger area or surface. Everyone must have seen a sheep's brain and noticed these folds. Sheep, however, are troubled with very few folds and very little intelligence. In man, the folds or convolutions are very numerous, and are supposed to represent the development of intelligence. If you imagine the inside of a skull, the cerebrum, or greater brain, occupies all that portion above the eyebrows and above the ears. At the back, below the level of the ears, we have the cerebellum, or smaller brain. Its function is not entirely unravelled. It partly has to do with steering our movements and controlling them. But the scope of this paper does not reach so far, so I will direct my remarks rather to the cerebrum. The cerebrum is mapped out into areas in connection with the functions of sight, hearing, taste, smell, touch, speech and motor cells for the movements of the muscles of the body. Finally, the anterior part of the brain has to do with attention, memory, and analysis of all the mental processes.

[insert image vol 14 pg 321-9 here]
Brain Areas—The motor and sensory areas are indicated by the names. In front of the motor areas is the Prefrontal (P.F.), "the commandment." M is the medulla or "commissariat"; all between is the "combatant force."

In the plate the word "leg" is wrongly placed, it should be more forward.

The different centres of education are indicated by their names. The impulses enter by the eye and the ear to their respective nerve roots A or B, and thence to the nerve centres. The arrows indicate the direction and course of nerve motion. The hand and speech centres send messages to the lower nerve centres or roots, which call the muscles into action.

Sight occupies the posterior part of the brain. It is a large area, for we are essentially seeing animals. It is the essence of our intellects. Sight is a very important and large function. There is one part which is limited to the seeing and understanding of written language. At times a blood clot will shut off the supply of nourishing blood to this limited area. In these cases the victims cannot read a letter or newspaper. Printed or written matter no longer conveys any ideas to their minds. Yet, presuming that the hearing centre is intact, they can understand anything that is read or spoken to them. A much larger area exists for ordinary vision, for seeing any object, or colour. I have been struck with the simile between this portion of the brain and photography. We all know that a sensitized plate or film requires a certain exposure in order to produce a good effect or picture. It is just so with these brain cells. A fleeting image, like an underexposed photograph, soon fades out of memory. Example: if you meet a person once for a short period you may not remember their features in two or three days. How different is it if you meet them daily for a month. Or, to take another example: I met an old friend recently whom I had not seen for twenty-five years, but we had lived in the same house for a year; hence, though the mental impressions or photographs might be dimmed by the hand of time, yet we recognized each other as if we had parted quite recently. But the great moral to draw from this simile is to cultivate the powers of observation, so as to grasp the details of the objects we look at. Train the young to observe accurately and, if possible, quickly, gathering in all the points as to shape, colour, size, and so forth. Those who have to educate the young should make a great point of this, as at this period the powers of focussing the attention may be stimulated and developed.

The centres for hearing lie at the sides of the brain, above and behind the temples. It is not a large area, but like the sight area is by reason of our high development split up into two parts. One part hears and records language, while the larger area records other sounds, such as music and noises.

Language in four different ways is represented in our brain. It is a highly intellectual qualification, and places us in lofty dominion above the beasts of the field, who can only utter sounds. If a human being be born without the faculty of language, then he or she may be deficient mentally, and poor thing, its intelligence may be reduced to that of the animals of the lower creation. The manifestation of language is in speech. There is a comparatively large area of the brain devoted to this faculty. It lies in the region of the left temple, in the motor area of lips and mouth. It is a singular fact that the organ of speech is on the left side. This is partly because we are essentially left-brained individuals. There are two halves of the brain, right and left, each apparently the same. But the left brain controls the right half of the body, and vice versa. As we are right-handed individuals, our left brains are more active and powerful than our right brains. There is, however, a similar speech centre in the right brain, and it is thought that it acts feebly and sometimes comes to the rescue when people get a paralysis on the left brain.

Great orators are, as a rule, well-developed in the speech area. This has often been confirmed by examination of the brains. Gambetta had a large development of this convolution, called Broca's convolution, after the name of the French physician who discovered its function.

But while Nature may endow an individual with a power over language and oratory, it does not follow that the whole intelligence is likewise favoured. Indeed, it is so often otherwise, that we sometimes describe a man's oratory as mere "gifts of the gab," in order to indicate by contrast a deficiency of his other intellectual talents.

At each side of the brain, a little above and behind the ear, are two other important centres or areas, those of taste and smell. These, however, do not call for special notice. More important is a large area occupying the middle of the outer surface of the brain on each side. This is the sensori-motor area. Here are large areas given up to receiving all the sensations of the skin, whether of heat or cold, pain or merely touch. Also, in correspondence with these cells are motor cells, which start or originate the movements of all the voluntary muscles of the limbs and body. As one would expect, the hinder part relates to the legs and trunk; then, advancing forward, one comes to areas controlling the arms, hand, neck, and face. It is in the area that controls the lips and tongue that we find the speech area.

Another point of interest is the comparative area given up to different functions. Exceptionally large in proportion is the area of the hand, as compared with the rest of the upper limb, showing that the hand and thumb are to be used as skilled instruments, in contrast to the coarser movements at the shoulder and elbow.

We have not been able by experiment or observation to unravel the frontal area of the forebrain. It was originally thought that the mind resided in this part, but we now know that mental operations involve the activity of all parts of the brain. But experiments show that the forepart of the brain has to do with the movements if the eyes and ears, which imply attention. Animals deprived of their forebrains lose all interest in surrounding objects and become listless, and will die of starvation rather than feed. Thus we are led to infer that the forebrain fixes the attention and supervises the other parts.

If a pigeon has its forebrain cut out, it sits listless and takes no notice of its surroundings, being unable to analyse them. It will die of starvation though food be close by. On the other hand, if food be placed in its beak it swallows perfectly. The reason is that the lower brain centres now come into play for this mechanical act.

If we apply the moral of this experiment to our children when we find them listless and inattentive, we know their forebrains are inactive, I might say asleep. It is then our duty to trace the cause. Is it laziness? Possibly, but probably not. Is it exhaustion? Yes, if there has been overwork or study, in which case rest is needful. Or is it debility? In most cases this is the cause. The child wants more air, more food, more rest and play. When this is overcome, the forebrain returns to activity.

While describing these brain centres, or areas, with their various functions, it must have occurred to some of you as to how these areas with their millions of cells are connected with each other. I purposely postponed this part till I had made clear the fact of various groups of cells being allotted with different functions. I would liken these brain areas and their component cells to so many electric batteries, which may be used as telephonic or telegraphic centres. As in the case of these, the cells are joined by wires, and one telephone centre is connected with so many others by other wires, so it is with the brain. There are brain fibres, which connect one cell with another, or one centre with another centre. Each brain cell has two kinds of fibres. At its outer or pointed apex it has a group of branching cells, which are often compared to the roots of a tree. These fibres are called "dendrons" (Greek—dendron, a tree). They act as receivers to the brain cell. They receive impressions from other cells, whether it be of sensation or of sight, taste, smell, or hearing. An impulse is received, stimulating that cell to its particular form of activity, with the result that a wave of nerve motion passes out of the cell by another fibre at its base, which fibre we call "an axon."

To make the subject more clear: you touch the push of an electric bell, thereby sending an electric impulse into the cell. The cell emits an electric force which rings the bell. Apply this now to the brain. If the skin of the hand be pricked or burnt, the sensation of pain is received by a sensory brain cell, and the message is sent to the motor cells of the hand. As soon as the "dendron" fibres of the motor cells receive the intelligence that pain is being experienced in the hand, they send out motor force to the hand muscles with instructions to withdraw the hand. All this is the work of an instant, and it almost paralyses the imagination to think of the millions of cells that are in constant activity during mental operations. It might easily suggest itself that with the millions and billions of nerve fibres some confusion would arise from contact. That there is confusion among the brain cells we are all of us at times painfully conscious. But Nature provided that there should be no mixture of messages, by crossing from one fibre to another. The brain fibres which carry the messages are all carefully ensheathed and insulated. Each fibre has a double sheath, and if in disease the sheath disintegrates, then loss of brain power and mental death begins in that particular cell or system, or, as we call it, neurone. "Association centres" is the term given to groups of cells and fibres, which are the latest and highest developed, and connect up different important areas or centres. They are like central telephone depots, which you ring up to switch you on to some particular office or wire. In this way we have in simple matters all the sensory nerves of the body connected with the motor cells. This is essential, so as to guide and protect all our movements.

(To be continued.)

Proofread by Leslie Noelani Laurio, December 2008