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3 ^ofir



THE



PEDAGOGICAL

/'SEMINARY.

AN

International Record of Educational Literature,
Institutions and Progress.

edited by
G. STANLEY HALL,

President of Clark University and Professor of Psychology and Education.



VOL. VI.

1898-99.



WORCESTER, MASS.:
PUBLISHED BY J. H. ORPHA.



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LIBRARY OF THE
iELAflO CTAfJFORO JR. UNIVER8IV

SEP 4 ^WO

COPYRIGHT, 1898, BY G. .STANI^EY HAI^I^.

C



PREM OF OLIVER B. WOOD,
WORCESTER. MAM.



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*

V



THE

Pedagogical Seminary.

Founded and Edited by G. Stani^by Hai<i,.
Voi<. VI. OCTOBER, 1898. No. i.

EDITORIAL.



With the first number of a new volume, we present our
readers with two articles on subjects of general importance.

The first develops a distinction between the large fundamental
muscles that move the large joints, that unfold first and repre-
sent to some extent motions which man has in common
with the higher animals, are the last to be affected in all de-
generative motor diseases on the one hand and on the other,
the smaller muscles of face, fingers, articulation apparatus,
which are called peripheral or accessory, develop later, and are
functionally superposed upon the more central system, are quite
liable to be involved in school-bred automatisms and chorea,
represent finer, more rapid, specialized and exact movements,
and whose changing tensions are very closely connected with
thought and all psychic activities.

Mr. Burk has for the first time pointed out the relation of
this distinction to Flechsig's recent differentiation between the
projective system and the *' association fibres" of the brain,
both ends of which are in the cranium, and which connect
areas of the posterior and especially frontal areas, to the
possible functions of Vulpius* transverse fibres of the middle
layer, and also to the higher and third level of Hughlings
Jackson. He then proceeds to state the pedagogic implications
of this view point. (P. 20.)



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4 EDITORIAL.

Selecting the hand, and leaving speech development for later
and more detailed treatment, he shows how recent research gives
it a far higher function than had hitherto been conceded, as
the best index of intellectual power, and traces in some de- '
tail and with much recent new matter, its evolution from a
foot as coincident with that of intelligence, and by implication
its importance in education. On the whole, the article sum-
marizes and brings into new and very suggestive relations to
each other and to school work and educational philosophy
generally, a great variety of special investigation not readily
accessible.

In the article on Inhibition, the author briefly indicates the
views of Herbart, Benecke, Taine, Roux and others who have
studied the problem of the arrest of one function by another which
absorbs mote than its share of energy, and undertakes to ex-
plain restlessness. Suggestive as the article is, it only opens
to others a glimpse into a fiar vaster and unexplored realm,
further treatment of which may be expected in these pages.

Dr. Lukens, who had been connected with Clark University
for several years, spent the last academic year travelling in
Europe, with the purpose of seeing as many educational institu-
tions and mpn of diflferent countries prominent in pedagogical
work as possible. At the editor's request he has jotted down,
very informally, some of his observations, and expressed with
great frankness his impression of men, opinions, and methods
in a way sure to be helpful.

Many reviews and book notes are crowded out and will appear
in the next number.



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FROM FUNDAMENTAL TO ACCESSORY IN THE
DEVELOPMENT OF THE NERVOUS SYS-
TEM AND OF MOVEMENTS.



By F&BDBRic BURK, Fellow in Clark University.



Two tendepcies in educational method have ever struggled
in gueater or less opposition — one based upon the logical divi-
sions of the subject studied ; the other based upon some theory
of internal order of development in the mentality of the pupil.
Theoretic pedagogy has made the latter tendency its conten-
tion. Commenius, Rousseau, Froebel and others have gaine<i
the title of " reformer'* essentially because they attempted to
break away from a form of education determined by the logi-
cal order of subject-matter and sought to substitute for it some
theory of the psychologi9al development of the pupil as th^
regulative principle. It is not until the question is brought
under close scrutiny of experience or of theory, that the possi-
bility of an essential difference between the logical order of
subject-matter and the pedagogical order of mental develop-
ment presents itself in any convincing way.

To illustrate : in learning to read, the logical order naturally
shows us that sentences are made up of words, words of sylla-
bles, and syllables of letters ; it would seem that letters being
the ultimate logical simples would also be the ultimate peda-^
gogical simples and the point of beginning for the learner."
Such, indeed, was the method employed in schools universally
until very recent times, and it still is widely used in some
countries. But experience has shown conclusively, neverthe-
less, that in this matter at least, the avenue of least resistance
is not upon the lines of logical cleavage, but on the contrary,
it has been found that children learn to read far more readily
by beginning with words or even sentences. Thus, in this case,
the pedagogical order is almost the reverse of the logical order^
In certain other forms of instruction, experience has as de^
nitely established a conflict between the pedagogical develop-
ment of pupil and logical order of subject which makes it
doubtful that the latter is as serviceable for educational purposes
as practice has often assumed.

The educational reformers — some by theoretic deductions
and others by experience or by happy intuition — have attempted



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6 DEVELOPMENT OF THE NERVOUS SYSTEM.

to bring into clearer light a subjective order in the development
of mentality. Froebel, Herbart and many others certainly
have made many valuable contributions which have stood tests
of experience. But we have as yet no general basis in positive
science for such an order ; and it would seem natural that the
modem biological sciences — ^particularly neurology and exper-
imental psychology — should make contributions to this problem.
For the purpose of bringing together in convenient form such
scattered facts in these sciences as bear directly or indirectly
upon the problem, this study has been undertaken. The first
chapter will review the contributions in the field of recent
studies of the nervous system ; the second chapter will trace
the development of the human hand and attempt to correlate
this development with that of the nervous system. A third
will review studies upon the growth of hand motility during
the school ages.

Suggestions from the Development of the Nervous

System.

It was but natural, in the early attempts to find a relation
between the various structures of the nervous system and the
difierent degrees of mentality observable in masses of individ-
uals, that attention should have first been turned upon the
grosser forms of brain anatomy — the shape and protuberances
of the skull, arrangement of the convolutions, the size and
weight of the brain, etc. Each of these features has been
subjected to scrutinizing comparative study. Practically noth-
ing, however, of psychological significance has thus far been
obtained from any of these studies, except to render it more
doubtful that any significant relation exists between these
gross difierences which naked eye or scales may detect, and
the difierences of mentality in individuals. Large differences
in weight, for example, are shown to depend chiefly upon
variations in the amount of non-nervous material — the sup-
porting tissues, blood vessels, fluids, ajid the fatty protecting
sheaths encasing nerve fibres. Recent investigation has been
gravitating toward a solution in the finer microscopical struc-
tures of nervous tissue. While as yet the interpretation of
facts in this field is more or less doubtful, nevertheless certain
features are suggestive to psj^hology and education.

Growth of the Brain in Vmght, For the sake of complete-
ness it may be well to mention in passing the result of recent
inquiries into the periods of brain growth as determined by
weight. Vierordt from records of 415 males and 424 females,
ranging to 25 years of age, finds that maturity in weight is
practically complete at about the eighth or ninth year. The
period of most rapid increase after birth, according to this in-



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DEVELOPMENT OF THE NERVOUS SYSTEM. ^

vestigation is fix>m birth to four years of age. Mies* places the
average weight of brains of new bom males at 340 grammes
and ot females at 330. At maturity he calculates the average
as 1,400 grammes for males and 1,050 grammes for females.
The period of most rapid growth is that of the first nine
months of life, during which one-third of the whole increase
after birth is added. The second third of the whole increase is
added between the ninth month and the twenty-seventh month.
The remaining third is slowly obtained. Mies says maturity of
weight is readied sometime between twenty and thirty years.
Pfister,^ in a study of 156 brains from birth to the fourteenth
year, confirms in a genend way the rate of growth as found by
Mies, and his figures would indicate that the maximum weight
is practically reached in the pubertal years.

While the data, from incompleteness and questionable accu-
racy, will not allow us to determine with absolute precision
when growth matures, we may nevertheless safely conclude
that the rate, rapid in embryonic life and infancy, steadily
decreases; and that, in all probability, no large increment of
weight is added after the ninth or tenth years.

Growth in the CeU Body and its Processes, The process of
division by which new cells are created ceases in the embryonic
period, as commonly stated, by the fifth month of foetal life.
Reflection upon this fact has left a fatalistic flavor in the con-
clusions of many, for it seems to limit the possibilities of educa-
tion. However, since the number of cells thus created reaches
the billions and there is evidence of what seems millions of un-
developed cells in the brains of men in their old age, it would
appear that our present stock of possibilities are by no means
exhausted. The nervous matter at any age shows what seems
to be stages in growth of cell body, and along with the devel-
oped cells are to be found small cells, which neurologists have
generally considered an undeveloped form awaiting structure
or ftmction, education or impulse, or whatever else the inciting
cause may be, to call them into active service. Kaiser* took
similar sections of the cervical region spinal cord in a new
bom child, a boy of 15 years and an adult. The number of de-
veloped cells in the new bom child was 104,270 ; in the youth,
211, 800 ; and in the adult, 221, 200. The number of cells which
came into ftmction during the firs^fteen years of life was there-
fore double the number at birth. From this observation it
would seem, that even in the spinal system, the earliest to

'Ueber das Gehimgewicht nengeborner Kinder. Wiener Klin.
Wockensch., 1889, p. 34.
^Da8 Himgewicht in Kindesalter, Archiv. f. Kinderheilkunde,

i8?7» PP- 164-192.
'Die Panktionen der Ganglienzellen dea Haltmark, 1891.



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8 DEVELOPMENT OF THE NERVOUS SYSTEM.

mature, growth of new powers is significantly active through-
out, until the adult period at least. VignaP finds that the cells
of the foetus are distinctly smaller than those of the child and
that they are more closely packed together. There is much
indirect evidence for the conclusion that the cell bodies are in-
creasing in size, though doubtless by such small increments as
to elude observation by the methods employed, throughout the
greater portion of adult life. Ramon y Cajal^ has attempted to
establish the principle that the size of a cell depends upon the
number of its processes and collateral branches, that is, upon
the number of other cells with which it is associated. Cajal
has also oflFered the plausible theory that the growth energy
which in early embryonic life is employed in cell division,
passes, when this process ceases, into the work of forming the
finer cell processes and collaterals and continues operative until
senescence sets in, /. ^., to the number of other cells with
which it is functionally associated.' There is also scattered
evidence to indicate that the cell changes in chemical constit-
uency with age. Dr. C. F. Hodge,* from a study of old and
young honey bees and of the cells of a foetus, a middle-aged
man and a man of 92 years, concludes that there are changes
of some character shown by difference in chemical reaction.
Bearing upon this point Donaldson in his resum^ of fatigue
says : ** In childhood the amount of stored material is small,
large in maturity, and small again in old age. Hence the cells
would by reason of this fact have the greatest capabilities for
work in the middle period. Between childhood and old age
there is, however, this difference, that while in the former the
non-available substances in the cell are developing, not yet
having material, those in the latter may become incapable of
reconstruction. ' ' *

Growth of Finer Microscopic Fibres. It is a speculation to
which neurological theories point, that the fibres which connect
different parts of the cortex, one with the other, are most likely
to be concerned in some way with association and the higher
forms of neuroses. As early as 1840, Remak made a study of
these *' tangential" fibres and concluded that no material
growth of these fibres took place beyond the eighth or tenth

* Development des Elements du Systeme Nerveus, 1889.
^Archiv. f. Anatomie, 1896, p. 191.

* Studies bearing upon this question will be found in Vignal's De-
velopment des elements du System nerveux c^r^bro-spinal, Paris,
1889 ; Krohn, Jour. Mental and Nervous Diseases, 1892 ; Donaldson,
Growth of the Brain, pp. 237-240, gives a resum^ together with a cut
reproduced from Vignaf showing comparative sections of cortex from
foetus, child at birth and adult.

*Jour. Phys., Vol. XVII, p. 130.

* Growth of Brain, p. 314.



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DEVELOPMENT OF THE NERVOUS SYSTEM. 9

year. Exner, in 1881, and Tuczek later, made some study of
the problem, and Fuchs found from 33 brains, confining him-
self to a single area in the posterior central gyrus^ that in the
outer layer of the cortex some tangential fibres appeared as
early as the fifth foetal month, and lat^r in the lower layers.
He thought the fibres reached their maximal number and size
in the seventh or eighth year. Obersteiner much later reaches
the same conclusion. In 1892 Dr. Oscar Vulpius,* of Heidel-
berg, made a more thorough and careful study from 22 brains
distributed in age as follows: 32d foetal week, 34th foetal
week, birth, 4J4 months, 8 months, 11 months, 16 months,
and i^, 25^, 3, 7, 10, 16, 17, 33, 79 years. He cut homol-
ogous sections from the first frontal gyrus (left), third frontal
gyrus (left), third frontal gyrus (right), anterior central gyrus
(right), occipital lobe (right), and first temporal gyrus (left).
After preparing and staining sections, he counted the tangen-
tial fibres in an area of a given size as they occurred in three
layers of the cortex. The more important conclusions reached
by Dr. Vulpius are that the tangential fibres begin in the outer |
and inner layer about the fifth month, and in the middle layerl
about the ninth month, that this growth does not cease in^
childhood, and that as late as the 17th year the increase of
tangential fibres is marked ; in old age an apparent decrease
in number takes place ; the greatest number of tangential
fibres is to be found in the central motor region ; poor nutri-
tion seems to inhibit the growth of tangential fibres. Some of
his results, as shown by charts, might h^ stated as follows : the
inner layer in all localities and practically all ages has far the
most tangential fibres and the middle layer the least; the
relative number of fibres in each layer varies widely in each
area, those of the central or motor region having the greatest
number ; the fibres of the inner layer develop their sheaths in
all cases earlier, and in the motor sight and hearing regions,
almost reach their maximum in number during the second
year, while in the speech and other centers, there is a gradual
increase until the eleventh year and a later gradual increment
until the 33d year at least ; the outer layer fibres follow in
general the course of growth of the inner layer, but contain
generally from one-eighth to one-half as many ; the middle
layer in no case makes an appreciable increase until puberty,
grows most rapidly in the early adult years, and never contains
more than a third as many fibres as the inner layer.

Kaes,in 1893, ^Y a comparative examination somewhat simi-
lar to that of Vulpius, shows so conclusively that the develop-
ment of fibres in the cortex, especially the tangential, is a

^Archiv. f. Psychiat. u. Nervenkrank, Vol. XXIII, 1892.



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lO DEVELOPMENT OF THE NERVOUS SYSTEM.

process still in active progress as late as the 39th year, that
Edinger, who in earlier editions of his " Nervose Central
Organ*' denied the demonstration of this, admits in his latest
edition (1896) that the principle has been established. In a
later study, Kaes comes to the conclusion that at 40 years of
age there is at least a partial arrest in the rapidity of growth
of these fibres. The small number of brains compared, how-
ever, makes this statement of little value.

Dr. Hamarberg, unfortunately cut short by death in the midst
of a most promising comparative study of normal and idiot
brains, nevertheless made a definite contribution.* He compared
homologous sections from the brains of nine persons ranging in
degree with similar sections from normal brains, comparing the
size, number and characteristics of the cells. In all cases the
brains of defectives showed marked deficiencies. The devel-
oped cells were far fewer in number and of irregular and
retarded development. His study leads to the conclusion that
the idiot brain is one which has suffered arrest of development
in some particular, involving larger or smaller areas of the
brain, at some early period.

The more recent studies by Kaes upon fibre development
entirely corroborate this conclusion of Hamarberg. In a
recent contribution ^ he states conclusions from a detailed com-
parison he has made upon three brains ; that of those of
normal child 15 months old, a microcephalous idiot of 18
months, and a macrocephalic dwarf 25 years of age. The
dwarf was the size of a child of about nine years of age,
unable to speak or to understand language, and hampered by
dragging movements of the limbs. Dr. Kaes measured the
thickness of different layers of the cortex in several corres-
ponding parts of these brains and gives interesting tabular
results. He concludes that in development of the cortex the
dwarf of twenty-five years of age has not advanced beyond
that of the normal child of 15 months. The projection fibres
of the central convolutions are better developed in the normal
infant than in the dwarf, while the associational fibres which
connect convolutions, marked in the normal infant, are absent
in the dwarf. A feature that is common to both idiot brains is
the manifest arrest by development of the second and third
(Meynert)layers, and Dr. Kaes, from this and previous observa-
tions which he has made, feels justified in asserting that the
development of this cortical region is essential to psychic un-
foldment. A singular anomaly however is, that the external

^Stndien iiber Klinik u. Pathologie der Idiotic nebst Untersuchun-
gen iiber den Normalen Ban der Hirnrinde, 1890.

'Uebcr den Markfasergehalt der Hirnrinde bei Pathol ogischen
Gebirn. Deutsch W'chschr., Nos. 10 and 11, 1898.



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DBVBLOPMENT OF THE NERVOUS SYSTEM. II

tangential layer is broader and better developed in the idiots,
than even in adult normal brains. He offers as a possible
explanation the biologic fact that in the lower animal series
this layer is larger, comparatively, than in the higher animals,
and that in man it frequently appears only in rudimentary
fonn. This external layer develops as low down the scale as
reptiles, even prior to the projection system, and Dr. Kaes holds
the opinion that we must consider it the precursor or oldest
form, on the sensory side, of the projection system. Applied
as an explanation of the anomaly described. Dr. Kaes takes
the view that these idiots are arrested in development at an
early biologic stage and the relatively large amount of tangen-
tial fibres represents persistence of an old type. Further he
finds that the microcephalous infant had sufi^ed a complete
arrest of the development of the fibres of the central convolu-
tions while those fibres most directly in connection with smell
were retarded the least, which is significant in view of Edin-



Online LibraryNational Tuberculosis AssociationJournal of genetic psychology → online text (page 1 of 65)