site logo

Factors Determining The Efficiency Of The Nervous System

DEVELOPMENT AND NUTRITION.--Ignoring the native differences in nervous

systems through the influence of heredity, the efficiency of a nervous

system is largely dependent on two factors: (1) The development of the

cells and fibers of which it is composed, and (2) its general tone of

health and vigor. The actual number of cells in the nervous system

increases but little if at all after birth. Indeed, it is doubtful

r Edison's brain and nervous system has a greater number of cells

in it than yours or mine. The difference between the brain of a genius

and that of an ordinary man is not in the number of cells which it

contains, but rather in the development of the cells and fibers which

are present, potentially, at least, in every nervous system. The

histologist tells us that in the nervous system of every child there are

tens of thousands of cells which are so immature and undeveloped that

they are useless; indeed, this is the case to some degree in every adult

person's nervous system as well. Thus each individual has inherent in

his nervous system potentialities of which he has never taken advantage,

the utilizing of which may make him a genius and the neglecting of which

will certainly leave him on the plane of mediocrity. The first problem

in education, then, is to take the unripe and inefficient nervous system

and so develop it in connection with the growing mind that the

possibilities which nature has stored in it shall become actualities.

UNDEVELOPED CELLS.--Professor Donaldson tells us on this point that: At

birth, and for a long time after, many [nervous] systems contain cell

elements which are more or less immature, not forming a functional part

of the tissue, and yet under some conditions capable of further

development.... For the cells which are continually appearing in the

developing cortex no other source is known than the nuclei or granules

found there in its earliest stages. These elements are metamorphosed

neuroblasts--that is, elementary cells out of which the nervous matter

is developed--which have shrunken to a volume less than that which they

had at first, and which remain small until, in the subsequent process of

enlargement necessary for their full development, they expand into

well-marked cells. Elements intermediate between these granules and the

fully developed cells are always found, even in mature brains, and

therefore it is inferred that the latter are derived from the former.

The appearances there also lead to the conclusion that many elements

which might possibly develop in any given case are far beyond the number

that actually does so.... The possible number of cells latent and

functional in the central system is early fixed. At any age this number

is accordingly represented by the granules as well as by the cells which

have already undergone further development. During growth the proportion

of developed cells increases, and sometimes, owing to the failure to

recognize potential nerve cells in the granules, the impression is

carried away that this increase implies the formation of new elements.

As has been shown, such is not the case.[1]

DEVELOPMENT OF NERVE FIBERS.--The nerve fibers, no less than the

cells, must go through a process of development. It has already been

shown that the fibers are the result of a branching of cells. At birth

many of the cells have not yet thrown out branches, and hence the fibers

are lacking; while many of those which are already grown out are not

sufficiently developed to transmit impulses accurately. Thus it has been

found that most children at birth are able to support the weight of the

body for several seconds by clasping the fingers around a small rod, but

it takes about a year for the child to become able to stand. It is

evident that it requires more actual strength to cling to a rod than to

stand; hence the conclusion is that the difference is in the earlier

development of the nerve centers which have to do with clasping than of

those concerned in standing. Likewise the child's first attempts to feed

himself or do any one of the thousand little things about which he is so

awkward, are partial failures not so much because he has not had

practice as because his nervous machinery connected with those movements

is not yet developed sufficiently to enable him to be accurate. His

brain is in a condition which Flechsig calls unripe. How, then, shall

the undeveloped cells and system ripen? How shall the undeveloped cells

and fibers grow to full maturity and efficiency?