Psychological Clinic
The
Copyright, 1912, by Lightner Witmer, Editor.
Vol. VI. No. 4.
June
15,
1912.
PRELIMINARY REPORT ON THE TREATMENT OF STUTTERING, STAMMERING, AND LISPING IN A NEW YORK SCHOOL. By Michael
Levine, A.M.,
Teacher in Public School 6J+, New York
City.1
is: what is tlie difference between stuttering
The first
question stammering, terms layman? According to
interchangeably by the modern physiology they both denote a disease of the mechanism involved in the production of speech, disturbances in the organs governing respiration, phonation, and articulation. While many authorities differentiate stuttering from stammering, others claim that fundamentally they describe one and the same condition. Writers who have accepted the view that stuttering and stammering are one disease, have made subdivisions based on the kind of cramps experienced by the patient while speaking. For the purposes of this discussion, however, it will be
and
which
are
used
convenient to separate the two terms and to allot to each its
peculiar symptoms. may be used to denote faulty speech as a result of respiratory disturbances, the defects being in the muscles of respiration, or in the larynx, or in both. Stammering, on the other
Stuttering
hand, tion.
may be used to denote a disability of the muscles of articulaThese defects do not include disorders of speech associated
with brain as
lesions, or the conditions described under such terms Stammeln, Hornstummheit, or other speech abnormalities. The
possible physiological
causes
of
stuttering are very comdistinguished. Stuttering is impulses which pass not only controlling laryngeal activity, but also to those gov-
plicated, but two at least may be caused by highly intensified nervous to the nerves
erning other motor activities. In many instances these other activities at first offer relief, but finally become involuntary, so that the i Public School No. 64 Is under the supervision of Associate Superintendent Gustave Straubenmuller and District Superintendent John W. Davis, to both of whom the writer is Indebted for sympathetic co-operation, and also to Principal William E. Grady, whose suggestions and kind assistance made the work possible.
(93)
THE PSYCHOLOGICAL CLINIC.
$4
patient
is unable to
speak
In many cases, however, involuntary from the begin-
without them.
these associated motor activities are ning. This is self-explanatory when
we remember that the larynthe of branches vagus. All the muscles except the geal which innervated by the superior laryngeal, receive thyro-cricoid, nerve filaments from the inferior laryngeal branch of the vagus, nerves are
This cranial derived from the accessory roots. internal and other heart nerve sends off branches which supply the same the origin as organs. Moreover, the vagus has practically the fibres
being
glosso-pharyngeal and geal supplies motor fibres
the facial
The
glosso-pharynpharynx and the base of the tongue, and secretory fibres to the parotid gland. The facial motor branches supply the muscles of the face, scalp, and ear, while its secretory fibres supply the submaxillary and sublingual glands. It is not surprising, therefore, that in severe attacks of stuttering not only do the lips move, but also the head, the jaws, the eyes, the nostrils, the arms and the legs in a frantic endeavor to produce the desired sound. These are the external the
manifestations. such
There
nerves.
to the muscles of the
concomitant internal manifestations heart, dull pain in the stomach, parched
are
of the
palpitation depressing symptoms. Stuttering may be due to some aberration of the superior laryngeal or recurrent fibres. The temporary paralysis of these fibres deprives the stutterer of the power to speak because this nerve controls the smaller muscles of the larynx which in turn control the size of the glottis. The sudden changes in the larynx destroy the rhythm of breathing which is of fundamental importance to normal speech. As distinguished from stuttering, the term stammering may be used to denote defects of the speech organs employed in producing consonants. The patient repeats involuntarily the sound of a consonant several times before he can glide on to the next sound. As a rule the stammerer speaks very rapidly when he is In all cases there seems to be a lack of not in difficulty. proper respiratory control. The views expressed by the leading German authorities (see bibliography, page 10G) show that at present there is no consensus of opinion as to the causes of stammering and stuttering. The as
throat,
and other
best ciiterion of their theories would be the results of methods \\ ithout doubt based upon them. many factors are involved in producing stuttering and stammering, and many causes are assigned, the most common of which are fear, to
imitation, injury
STUTTERING, STAMMERING,
AND LISPING.
95
heredity. An investigation of thirtyfollowing causes. In the case of the four marked "unknown," the parents simply stated that their children had suddenly developed the habit.
organs of
and
articulation,
two cases showed the
TABLE I.
CAUSES OF STUTTERING AND STAMMERING.
7 8
Imitation Results of disease Nervousness caused
13
by fright
4
Unknown
and
32
The defects made their appearance between the ages of five eight years, and in but one case did a pupil begin to stammer
after he had attained the age of eight. Lisping is a relatively minor speech
absence of front teeth,
an
unusual
defect, usually due to protrusion of the lower jaw,
carelessness, and in many cases to a lack of knowledge concerning the position of the tongue and the shape of the mouth necessary to the production of various sounds. Assuming the truth of these fundamental considerations, yet remembering that our inferences are based on the limited material supplied by a single city school, let us inquire: (1) What is the percentage of stutterers, of stammerers, and of lispers in the school ? (2) What effect does school life have on the production of speech defects ? (3) What specific remedial measures may be adopted? The figures given in Table II are very conservative, in that they represent only the pupils who are sent to the speech class because their speech is so poor as to handicap their progress. It is probable that a thorough examination of all the pupils in the to
school would
largely
increase these
figures.
TABLE II. bchool Enrolment
2997
Per cent of defective
speakers
Per cent of stammerers and stutterers
Per cent of lispers or "babytalkers"
3.0
1.8
1.2
Investigations conducted abroad, in German and Belgium (see bibliography, page 106), show approximately similar results. As an index of general conditions the figures correspond to those given in table II, and while it may seem premature to generalize,
THE PSYCHOLOGICAL CLINIC.
96 it
yet
city
seems as
if
a
thorough investigation of the problem in our an even higher percentage of speech de-
schools would reveal
fectives here than abroad.
ascertaining the number of speech defective in schools, interesting problem would be to find the distribution of such pupils in the grades, with a view to drawing .conclusions as to the influence of school conditions in producing speech defects. A careful study of the problem of distribution and school influence by Eouma in Belgium showed that the proportion of In addition to
the
an
lispers
diminishes from the first to the sixth school year, while
proportion of stutterers and stammerers increases in the same period. His figures also show a gradual increase in the number of stuttering and stammering boys from the first to the fourth grades, as in the following table: the
TABLE III.
8 per cent
First year Second year
1.3
"
"
Third year Fourth year
2.0
"
"
2.4
"
"
Fifth year
1.8
"
"
"
"
Sixth year
2.3
Table IV shows the distribution of children with speech defects in Public School No. G4, New York City, (see page 97). In this table the number of stammerers, stutterers and lispers in each grade represents the number sent to the speech class by the grade teachers. Owing to duties imposed upon them by their parents, many of the children could not attend either the morning or
afternoon sessions.
As the table
shows, only
sixteen of the
thirty-seven lispers attended the speech class. A study of table IV will show that lisping is greatest in the early school years, and that it has a tendency to become less as we approach the third and centage of stammerers any
are
have
found in the as 4
fourth years. On the other hand the perand stutterers increases rapidly. Few if
early grades,
but the number increases until
eighth year of the elementary substantially in accord with the findings of Rouma. Apparently the school is increasing rather than decreasing the number of speech defects. It is true that, as Rouma has remarked, indifference and neglect on the part of parents, are factors contributing to the acquisition of habits of faulty we
course.
as
many These results
per cent in the are
STUTTERING, STAMMERING, AND LISPING. TABLE IV.?DISTRIBUTION OF DEFECTIVE SPEAKERS IN PUBLIC
STUTTERER8
AND
Stammerers
Lispers and "Babytalkebs"
}
?
So
a-S
o o
1A IB 2A 2E-2B 3A
3E-3B 4A 4E-4B 5A 5E-5B 6A 6E-6B 7A 7B 8A 8B Totals
75 204 145 174 188 187 184
NO.
Total Defective
Speakers
rt
11
ll5
II 0
1
0
4
1.9
0.7 1.1 1.5
1.3 1.9 2.7 1.1 1.0
0
5
3.4
0
4
1.1
2
2.6
0.5
1.0
2
5 3 6
0
3.2
190
1.0
0.5
1
3
252 237 253 243
2.3
3
1.2
1.5 1.6
4
10 7
2.3
0.7
0
8
3.7
0.8
0
11
1.3
1.5
3.2 1.5 3.9 2.9
189
3.1
0.5
0
7
155 127
1.2
1.2
0
4
2.3
3
95
4.2
2.1
0
3 7
99
3.0
1.0
1
4
3.1 4.5 3.7 2.5 2.3 6.3 4.0
1.2
16
92
3.0
2997
55
1.5
32
64
e5
11 Kgn
SCHOOL
97
37
speech by children, nevertheless, modern pedagogical methods probably produce many stutterers and stammerers. Devices such as perception cards, rapid oral arithmetic, rapid interrogation, compulsory answering irrespective of the pupil's readiness and willingness, and those school activities in general which require intense
mental effort combined with immediate oral response, frequently tend to transform a nervous tendency into a disease. There are, of course, still other factors within the control of the school. For example, a number of children who have been under instruction
speech class have relapsed into their former manner of after promotion into a new class. shortly speech Investigation has proved that various influences snch as nagging, over-pressure, sarcasm, and mimicry of classmates, all tend to disturb the pupil and hinder him from living up to the standards set for him in the speech class. The pertinent question still remains, Avhat specific remedial measures can be adopted to assist the child with defective speech. in, the
THE PSYCHOLOGICAL CLINIC.
98
problem is one of organization. There are various possimodes of grouping such pupils: (1) Isolation and segregation of speech defectives in a spe-
The first ble
cial of
a
of which shall last from 9 a. m. to 3 p. m. (2) Compulsory attendance of speech defectives in the room regular teacher, preferably a departmental teacher, who hav-
class, the session
ing been relieved of the school
of official class
session,
who report to his
pupils (3)
work,
instruction for
can an
give
hour
within the limits
or
more
daily
to
room.
before the
Attendance, compulsory or optional, of speech defectives regular session (8 to 8:30 a. m.) or after the regular
session
to 3:30 p.
(3
m.)
for instruction
by
a
regular
or a
special
teacher.
Looking at the problem in terms of a school district, rather than one particular school, attendance compulsory or optional at a centrally located school, conforming to any of the foregoing schemes. (4)
going into the relative merits of these various the it plans, may be remarked that it is inadvisable to isolate defectives as suggested in (1). We may well apply to such pupils the statement of Dr. flames Kerr Love with reference to the deaf. Without
Instead of stuttering, stammering or lisping being a reason for sending a child to a special class, it is a good reason for keeping him out of it. Grouping him with others like himself would make him
more
conscious of his condition and this consciousness would
become the basis of timidity. Moreover, it is obvious that normal pupils can set a better standard of speech than can any group of speech defectives. In connection with (2) it may be noted that a special class takes the pupil away from his regular lessons and retardation may result, not only directly from speech defects, but indirectly from absence during periods of instruction in sequential
subjects.
Conclusions like the above led to the organization in Public School T\o. 64 of a class which met for two short periods daily, one in the morning prior to the opening session (8 to 8: 30 a. m.), the other at the close of the session (3 to 3: 30 p. m.). The grade teachers
were urged to co-operate bv attending a session of the class to note the method of speech instructing the pupils, and by making the pupils conform to certain standards in the daily recitation. The speech defectives were told to consult with their regulai class teachers and to indicate their and readiness
willingness
STUTTERING, STAMMERING, AND
LISPING.
99
orally by raising the hand. When reciting, the pupils supposed to stand erect, to take deep breaths, to talk very slowly, and to try to vary the pitch. The teachers were requested To to encourage the pupils to live up to these requirements. in to recite to defectives response questions sharply compel speech put when they are not ready with an answer, frequently throws them iuto such a nervous state that in their attempt to answer, they will relapse into their former habits and nullify the results of
to recite are
instruction.
special
Three forms of exercises afternoon speech classes.
were
employed
in the
morning and
(1) An exercise to build up the weakened respiratory system. For this purpose, use was made of the "Two-minute drill" as given in the city schools. This drill, when properly done, becomes a "minute-and-a-half drill," and consists of deep breathing, armstretching, and forward bending at hips to touch tips of fingers to toes, knee-bending with thumbs locked behind back. Abdominal breathing was taught and a conscious use of this mode of breathing was encouraged. (2) A second exercise for the purpose of recapitulating the steps taken by a young child in acquiring speech. This exercise was based on Wundt's Development of Speech in Children (Entder wicklung Kindersprache). Inarticulate sounds (Schreilaute) gradually lead to the development of articulate sounds, and these in turn lead to the word in the sentence. (3) Ear training. This enables the pupil to hear his own voice and to make an effort to change the tone of his speaking voice from a low monotonous pitch to the modulated speech of a normal child. Inasmuch as speech defectives tend to crowd their
speech
and
ployed
give speech.
of his
faster tempo than the pupil a standard
use a
to
In the first
normal,
by
a
metronome was em-
which to
measure
the
gait
exercise, the effort is made not only to strengthen respiratory and circulatory system, but to impress upon the pupil the fact that proper breathing is a means of overcoming his difficulty. The child is placed on his back and told to inhale and to feel the movement of the belly wall during inhalation In a stutterer, during these and exhalation. respiratory movea marked of the ments, quivering diaphragm may be felt. The can not control his breath in exhalation, nor can he in any pupil way check the quivering of the diaphragm. Moreover, the breath-
the weakened
THE PSYCHOLOGICAL CLINIC.
100
very shallow. The pupil is made to realize these once puts forth a conscious effort to take deeper defects, and breaths to control the exhalation. Constant practice of abdominal breathing causes the spasmodic contractions of the diaphragm The to disappear and enables the pupil to control his breathing.
ing
is
usually
and at
strengthening the diaphragm are used. deeply and then to exhale slowly with the tongue, teeth and lips in the position for pronouncing At the beginning of the work, the length the consonants / or v. of time the child can sustain a tone is usually very short, but he is encouraged to hold a definite tone until perfect control of the diaphragm and larynx is obtained. To a moderate degree, relaxation of the muscles of the larynx is obtained through suggestions as to the poise of the head, absence of collar pressure, front or back, the necessity of talking "up," etc. After telling the pupil that he should have a sense of ease in the throat, breathing exercises are begun. Inhalation is performed very slowly, and exhalation asfollowing exercises The pupil is told
for
to
inhale
Inaudible at first, the sound becomes the sound of ah. in successive drills until finally it is normal. louder and louder The second exercise is then begun. Expiration takes the form of a vowel or a series of vowels, for the defective never sumes
falters on a vowel but always on a consonant. The vowels are sung and sustained at a definite pitch. In the early stages of the work, the duration of this sound varies from five to ten seconds, but after
days' practice, it reaches thirty to fifty seconds. That is during one exhalation, the vocal cords, the glottis and the diaphragm, can be so regulated as to allow the continuation of one sound for half a minute or longer. The exercise is repeated a
few
to say,
with each vowel in turn.
Later the vowels
are
combined with
single consonants, as ha, be, bi, bo, bu, and the series is gone through with one breath. Drills on the more difficult consonants follow, special attention being given to the peculiar difficulties of the individual children. To some g gives the most trouble, to others b, p, 1c, v, etc. Frequently, the initial consonant of the pupil's name is the most difficult. The most difficult consonant,
whatever it may be, is combined with a vowel and a method is devised by which the pupil eventually succeeds in producing it easily. This sound is then combined with another consonant and both are prefixed to vowels, as pra, pre, pri, pro, pru. The third exercise is intended to develop a keen sense of pitch and rhythm. The pupils find little difficulty in repeating the syllables mentioned, especially in a sing-song manner. The introduc-
LISPING.
STUTTERING,
101
speaking serves the very good purpose of develophabit; it produces a change of tone. To break the ing habit of speaking in a low-pitched monotone, all the of the pupils and vowels syllables were at first recited in a sing-song. This led The to the fourth development, namely slower, rhythmic speech. and of the a metronome use slower utterance was taught through intonation was secured through simple rhymes or jingles. Varied through imitation and by the use of charts containing sentences underscored with colored lines suggesting the proper variations of pitch. For example, in the following sentences the intonation is a rising or a falling one, according to the thought expressed in the sentence, and the pupil is taught to indicate the change in tone by raising or lowering the hand. The flag was raised. lion of
melody
in
a new
I walked down the I
jump
steps.
up and down.
Further sentences expressing everyday occurrences were put charts and colored chalk used in marking the vowels, each vowel being marked with a different color. on
Inasmuch
easiest for the pupil to sound, him and enable him to master the encourage In cases where the first word in a senconsonants more easily. tence begins with a consonant, and difficulty is encountered in sounding it, the pupil is taught to introduce a vowel before the For example, in the sentence, "Prince George became consonant.
this device
as
the vowels
are
seems to
King of England," getting a start, he "A
if the initial consonant prevents the pupil from is instructed to read the sentence as though it
Prince George," etc. Having once got under way through the help of such a device, the child encounters no further difficulty provided the respiratory activities are normal. He then practices the initial sound in this connection until he can repeat the sentence with ease. Merely suggesting that the pupil
were
say a word often enables him to do so; he becomes confident, and finds himself trying to verify his growing belief in his
can
ability. Drills in
reading the
vowels in
a sentence are also very helpchart and all the vowels are marked rhyme The pupil then reads the vowels in their characteristic colors. manner in a sing-song according to one of the five types of slowly in 1. The shown consonants are then slipped in and melodies Fig. in a musical tone. The selection entire sentence the read the pupils
ful.
A
is written
on a
THE PSYCHOLOGICAL CLINIC.
102
.o
s:
o
i
FIG. MELODIES. THE FIVE FIG. 1. 1. THE FIVE TYPE TYPE MELODIES.
and
presentation
should
of
reading material
is of
great importance,
and
come as a final step in the treatment. The pupils are taught to be self-critical of their speech. Inappropriate movements, a dull monotonous tone, lack of breath, careless pronunciation or enunciation,?all these faults arouse immediate criticism. Through experience the pupil learns (1) to inhale
until the
belly wall is well extended; (2) to speak slowly and in rhythm; (3) to use a melody; (4) to pay close attention to vowels; (5) to introduce a vowel when in straits. The application of these exercises was fraught with difficulty.
The oral rendition of any selection from the reader seemed to undo all that had been laboriously accomplished. The pupils still lacked power and confidence, and the sight of a reader or any
STUTTERING, STAilOfflZlZVG, AM LISPING.
103
other book made them revert to their old habits. This may have been due to the association of a reader with the unsympathetic audience in the classroom.
For
a
long
time it
was
hard to
develop
type of recitation other than that of question and answer, which would serve for the application of principles already taught; but the imitative instincts of the children suggested a plan which was followed with excellent results. They originated games which a
nothing less than a dramatization of familiar occupations. The One game that proved very effective was called "grocery." and then in a first told could be what grocery store, bought pupils chose a grocer, several clerks, errand boys, and so on. Although it usually required an entire period for the mere organization of
were
the game, it was worth while because it aroused a deep interest in the work. The pupils talked freely and seemed to forget their difficulties. The next two or thrtee periods were spent in buying at
the
taking in
imaginary shop, their
respective
the grocer, his clerks, and the purchasers positions, and conducting the transactions
This type of play became very popular manner. with the children. The transition from this to the dramatization of reading material would not be too difficult. a
realistic
The
course
of work
outlined above tended to make the optimistic. Each felt that through his
briefly
stutterers and stammerers
efforts he had ceased to be a legitimate object for the gibes of his classmates. Even if he had not been entirely cured, at least he felt more confident of his ability to improve, and the attempt had been made to imbue him with the idea that if he faithfully followed up the work he was bound to succeed. own
Lispers include
that group of defective speakers who are certain letters their proper sounds. This inability give due to be the persistence of a habit formed in childhood of may the final dropping syllable or of substituting sounds for those in a word. The latter form of speech is often called required
unable to
"baby-talk"
or
more
due to malformation case of many foreign
properly "infantile late development
or
stammer". It may be of the teeth, and in the
pupils, to a lack of knowledge as to the position of various parts of the articulatory apparatus for the production of certain sounds. Figure 2 shows the position of the tongue, teeth and lips to form such difficult sounds as r, tli, I, s, v and wh. Investigation disclosed the fact that the most difficult sounds were the six just mentioned, and w, z, d and t. The s and 2 are espe-
cially difficult for children who lack the incisor or canine teeth, and they frequently substitute th for s or z. The I, r, t, d, wh and
104
CLINIC. PSYCHOLOGICAL THE
* V FIG. 22
\
wK.
POSITIONS OF THE TONGUE, TEETH TEETH AND LIPS TO FORM THE SIX MOST DIFFICULT SOUNDS.
STUTTERING, STAMMERING,
AND LISPING.
105
usually mispronounced because of inability to place the tongue, teeth and lips in the proper position. In correcting such defects the work is individual. Each is and his difficulties In understood. studied pupil thoroughly done cases where could because of be the condition of the nothing
w
are
teeth,
the children
were
advised to consult
a
dentist and then
the class. The pupil who lisps the I, is brought before mirror and shown how to place his tongue in order to sound the
return to a
letter.
He then
words
containing I,
and
practice reading from a book follows. To make the sound of s, the pupil is told to close his teeth and to touch them lightly with his tongue. After he masters the position he is told to blow his breath between his teeth. The letter r is sinned against chiefly by our foreigners and "baby-talkers". It is especially difficult for Russian Jewish children. The tongue plays an important part in the production of the r sound, being placed opposite the middle of the hard palate and vibrated while its outer edges rub against the hard palate. This sound, like the I, is taught with the aid of a mirror, and also by imitation of another pupil who practices at repeats
numerous
in
the
same
time.
Wh is not
a
difficult sound, except for the for-
is told to protrude his lips in the form of a funnel and to blow out his breath as if trying to cool a spoonful of hot liquid. V, which is sometimes interchanged with w, is made by placing the upper teeth on the lower lip and blowing the breath between the lip and the teeth. Tli, a sound incorrectly
eigner.
The
pupil
many, is made by placing the tip of the tongue between the upper and lower teeth and quickly withdrawing the tongue while allowing the breath to escape between the teeth. The sound may also be made by opening the teeth and forming a slip between the upper teeth and the tongue, but the former method was used because it proved to be easier. T is made by placing the tongue
given by
the upper teeth, d by placing it on the hard palate near the The mouth, of course, is open and the breath is forced out while the tongue is rapidly moved downward. Only two pupils found trouble in forming the cli and sh on
teeth.
which as they gave them, were thick and resembled the On close examination it was found that the steam. of escape mouth was drawn to one side and the sound emitted through an aperture made by the lips and teeth. The defect was overcome
sounds,
by making teeth
as
the
much
pupil control the motion of his lips and possible when producing th'e sounds.
as
close the
THE PSYCHOLOGICAL CLINIC.
106
urgently needed. pupils who are not cured in a reasonable time, because of conditions obviously other than weak mentality. Pedagogical investigation should discover a method for the successful treatment of theste peculiar cases. Statistics should be collected for the purpose of determining the character of the speech of pupils in city schools, so that the investigator of speech defects may give his attention to those groups Further
study of speech defectives Physiological investigation should be made
is
of
which most need his assistance. BIBLIOGRAPHY.
of Phonetics, with directions for the cure of stammering. The Faults of Speech. Xeueste Erfahrungen uber Sprachstorungen; 11)01. Uber die pUdagogische Behandlungen stotternder Kinder in den Schulen; 18S9. Fach, M. Die Behandlung stotternder Schiiler; 1894. Grunbaum. Erklarung des Stotterns. Gutzman, H. Das Stottern, I, II; 1899. Uber die Verhiitung und Heilung der wichtigsten Sprachstorungen; 1898. Die Gesundheitspflege der Spraclie. Hinckley, A. C. A Speech Defect Case Treated at Columbia University. The Psychological Clinic, November 15, 1911. Textbook of Physiology. Howell. Konigs. Die Behandlung stotternder Kinder; 1897. Lewis. Practical Treatment of Stammering and Stuttering; 1902. Stotternde Kinder; 1903. Liebmann. Vorlesungen iiber Sprachstorungen stotternder Kinder; 1898. Uber Sprachstorungen; 1904. Meiinert. Ott. Practical Physiology. Was hat die Scluile zu tun um die Sprechfehler zu bekiiinpfen ? Rogge. 1895. Rouma. EnquOt Scolaire snr les Troubles de la Parole chez Ecoliers Beiges; 1906. Treatment of Stuttering and Stammering; 1907. Scrifture. Treatment of Negligent Speech by the General Practitioner; 1908. Stewart. Manual of Physiology. Stegemann. Heilung d?s Stotterns; 1903. Die Behandlung stammelnder und stotternder SchUlkinder; Stotzner. 1891. Strumpell. Piidagogisclie Pathologie; 1899.
1. Bell. 2. 3. Coen. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 21. 22. 23.
Principles
24. 25. Wundt.
Physiologische Psychologic.
The
Copyright, 1912, by Lightner Witmer, Editor.
Vol. VI. No. 4.
June
15,
1912.
PRELIMINARY REPORT ON THE TREATMENT OF STUTTERING, STAMMERING, AND LISPING IN A NEW YORK SCHOOL. By Michael
Levine, A.M.,
Teacher in Public School 6J+, New York
City.1
is: what is tlie difference between stuttering
The first
question stammering, terms layman? According to
interchangeably by the modern physiology they both denote a disease of the mechanism involved in the production of speech, disturbances in the organs governing respiration, phonation, and articulation. While many authorities differentiate stuttering from stammering, others claim that fundamentally they describe one and the same condition. Writers who have accepted the view that stuttering and stammering are one disease, have made subdivisions based on the kind of cramps experienced by the patient while speaking. For the purposes of this discussion, however, it will be
and
which
are
used
convenient to separate the two terms and to allot to each its
peculiar symptoms. may be used to denote faulty speech as a result of respiratory disturbances, the defects being in the muscles of respiration, or in the larynx, or in both. Stammering, on the other
Stuttering
hand, tion.
may be used to denote a disability of the muscles of articulaThese defects do not include disorders of speech associated
with brain as
lesions, or the conditions described under such terms Stammeln, Hornstummheit, or other speech abnormalities. The
possible physiological
causes
of
stuttering are very comdistinguished. Stuttering is impulses which pass not only controlling laryngeal activity, but also to those gov-
plicated, but two at least may be caused by highly intensified nervous to the nerves
erning other motor activities. In many instances these other activities at first offer relief, but finally become involuntary, so that the i Public School No. 64 Is under the supervision of Associate Superintendent Gustave Straubenmuller and District Superintendent John W. Davis, to both of whom the writer is Indebted for sympathetic co-operation, and also to Principal William E. Grady, whose suggestions and kind assistance made the work possible.
(93)
THE PSYCHOLOGICAL CLINIC.
$4
patient
is unable to
speak
In many cases, however, involuntary from the begin-
without them.
these associated motor activities are ning. This is self-explanatory when
we remember that the larynthe of branches vagus. All the muscles except the geal which innervated by the superior laryngeal, receive thyro-cricoid, nerve filaments from the inferior laryngeal branch of the vagus, nerves are
This cranial derived from the accessory roots. internal and other heart nerve sends off branches which supply the same the origin as organs. Moreover, the vagus has practically the fibres
being
glosso-pharyngeal and geal supplies motor fibres
the facial
The
glosso-pharynpharynx and the base of the tongue, and secretory fibres to the parotid gland. The facial motor branches supply the muscles of the face, scalp, and ear, while its secretory fibres supply the submaxillary and sublingual glands. It is not surprising, therefore, that in severe attacks of stuttering not only do the lips move, but also the head, the jaws, the eyes, the nostrils, the arms and the legs in a frantic endeavor to produce the desired sound. These are the external the
manifestations. such
There
nerves.
to the muscles of the
concomitant internal manifestations heart, dull pain in the stomach, parched
are
of the
palpitation depressing symptoms. Stuttering may be due to some aberration of the superior laryngeal or recurrent fibres. The temporary paralysis of these fibres deprives the stutterer of the power to speak because this nerve controls the smaller muscles of the larynx which in turn control the size of the glottis. The sudden changes in the larynx destroy the rhythm of breathing which is of fundamental importance to normal speech. As distinguished from stuttering, the term stammering may be used to denote defects of the speech organs employed in producing consonants. The patient repeats involuntarily the sound of a consonant several times before he can glide on to the next sound. As a rule the stammerer speaks very rapidly when he is In all cases there seems to be a lack of not in difficulty. proper respiratory control. The views expressed by the leading German authorities (see bibliography, page 10G) show that at present there is no consensus of opinion as to the causes of stammering and stuttering. The as
throat,
and other
best ciiterion of their theories would be the results of methods \\ ithout doubt based upon them. many factors are involved in producing stuttering and stammering, and many causes are assigned, the most common of which are fear, to
imitation, injury
STUTTERING, STAMMERING,
AND LISPING.
95
heredity. An investigation of thirtyfollowing causes. In the case of the four marked "unknown," the parents simply stated that their children had suddenly developed the habit.
organs of
and
articulation,
two cases showed the
TABLE I.
CAUSES OF STUTTERING AND STAMMERING.
7 8
Imitation Results of disease Nervousness caused
13
by fright
4
Unknown
and
32
The defects made their appearance between the ages of five eight years, and in but one case did a pupil begin to stammer
after he had attained the age of eight. Lisping is a relatively minor speech
absence of front teeth,
an
unusual
defect, usually due to protrusion of the lower jaw,
carelessness, and in many cases to a lack of knowledge concerning the position of the tongue and the shape of the mouth necessary to the production of various sounds. Assuming the truth of these fundamental considerations, yet remembering that our inferences are based on the limited material supplied by a single city school, let us inquire: (1) What is the percentage of stutterers, of stammerers, and of lispers in the school ? (2) What effect does school life have on the production of speech defects ? (3) What specific remedial measures may be adopted? The figures given in Table II are very conservative, in that they represent only the pupils who are sent to the speech class because their speech is so poor as to handicap their progress. It is probable that a thorough examination of all the pupils in the to
school would
largely
increase these
figures.
TABLE II. bchool Enrolment
2997
Per cent of defective
speakers
Per cent of stammerers and stutterers
Per cent of lispers or "babytalkers"
3.0
1.8
1.2
Investigations conducted abroad, in German and Belgium (see bibliography, page 106), show approximately similar results. As an index of general conditions the figures correspond to those given in table II, and while it may seem premature to generalize,
THE PSYCHOLOGICAL CLINIC.
96 it
yet
city
seems as
if
a
thorough investigation of the problem in our an even higher percentage of speech de-
schools would reveal
fectives here than abroad.
ascertaining the number of speech defective in schools, interesting problem would be to find the distribution of such pupils in the grades, with a view to drawing .conclusions as to the influence of school conditions in producing speech defects. A careful study of the problem of distribution and school influence by Eouma in Belgium showed that the proportion of In addition to
the
an
lispers
diminishes from the first to the sixth school year, while
proportion of stutterers and stammerers increases in the same period. His figures also show a gradual increase in the number of stuttering and stammering boys from the first to the fourth grades, as in the following table: the
TABLE III.
8 per cent
First year Second year
1.3
"
"
Third year Fourth year
2.0
"
"
2.4
"
"
Fifth year
1.8
"
"
"
"
Sixth year
2.3
Table IV shows the distribution of children with speech defects in Public School No. G4, New York City, (see page 97). In this table the number of stammerers, stutterers and lispers in each grade represents the number sent to the speech class by the grade teachers. Owing to duties imposed upon them by their parents, many of the children could not attend either the morning or
afternoon sessions.
As the table
shows, only
sixteen of the
thirty-seven lispers attended the speech class. A study of table IV will show that lisping is greatest in the early school years, and that it has a tendency to become less as we approach the third and centage of stammerers any
are
have
found in the as 4
fourth years. On the other hand the perand stutterers increases rapidly. Few if
early grades,
but the number increases until
eighth year of the elementary substantially in accord with the findings of Rouma. Apparently the school is increasing rather than decreasing the number of speech defects. It is true that, as Rouma has remarked, indifference and neglect on the part of parents, are factors contributing to the acquisition of habits of faulty we
course.
as
many These results
per cent in the are
STUTTERING, STAMMERING, AND LISPING. TABLE IV.?DISTRIBUTION OF DEFECTIVE SPEAKERS IN PUBLIC
STUTTERER8
AND
Stammerers
Lispers and "Babytalkebs"
}
?
So
a-S
o o
1A IB 2A 2E-2B 3A
3E-3B 4A 4E-4B 5A 5E-5B 6A 6E-6B 7A 7B 8A 8B Totals
75 204 145 174 188 187 184
NO.
Total Defective
Speakers
rt
11
ll5
II 0
1
0
4
1.9
0.7 1.1 1.5
1.3 1.9 2.7 1.1 1.0
0
5
3.4
0
4
1.1
2
2.6
0.5
1.0
2
5 3 6
0
3.2
190
1.0
0.5
1
3
252 237 253 243
2.3
3
1.2
1.5 1.6
4
10 7
2.3
0.7
0
8
3.7
0.8
0
11
1.3
1.5
3.2 1.5 3.9 2.9
189
3.1
0.5
0
7
155 127
1.2
1.2
0
4
2.3
3
95
4.2
2.1
0
3 7
99
3.0
1.0
1
4
3.1 4.5 3.7 2.5 2.3 6.3 4.0
1.2
16
92
3.0
2997
55
1.5
32
64
e5
11 Kgn
SCHOOL
97
37
speech by children, nevertheless, modern pedagogical methods probably produce many stutterers and stammerers. Devices such as perception cards, rapid oral arithmetic, rapid interrogation, compulsory answering irrespective of the pupil's readiness and willingness, and those school activities in general which require intense
mental effort combined with immediate oral response, frequently tend to transform a nervous tendency into a disease. There are, of course, still other factors within the control of the school. For example, a number of children who have been under instruction
speech class have relapsed into their former manner of after promotion into a new class. shortly speech Investigation has proved that various influences snch as nagging, over-pressure, sarcasm, and mimicry of classmates, all tend to disturb the pupil and hinder him from living up to the standards set for him in the speech class. The pertinent question still remains, Avhat specific remedial measures can be adopted to assist the child with defective speech. in, the
THE PSYCHOLOGICAL CLINIC.
98
problem is one of organization. There are various possimodes of grouping such pupils: (1) Isolation and segregation of speech defectives in a spe-
The first ble
cial of
a
of which shall last from 9 a. m. to 3 p. m. (2) Compulsory attendance of speech defectives in the room regular teacher, preferably a departmental teacher, who hav-
class, the session
ing been relieved of the school
of official class
session,
who report to his
pupils (3)
work,
instruction for
can an
give
hour
within the limits
or
more
daily
to
room.
before the
Attendance, compulsory or optional, of speech defectives regular session (8 to 8:30 a. m.) or after the regular
session
to 3:30 p.
(3
m.)
for instruction
by
a
regular
or a
special
teacher.
Looking at the problem in terms of a school district, rather than one particular school, attendance compulsory or optional at a centrally located school, conforming to any of the foregoing schemes. (4)
going into the relative merits of these various the it plans, may be remarked that it is inadvisable to isolate defectives as suggested in (1). We may well apply to such pupils the statement of Dr. flames Kerr Love with reference to the deaf. Without
Instead of stuttering, stammering or lisping being a reason for sending a child to a special class, it is a good reason for keeping him out of it. Grouping him with others like himself would make him
more
conscious of his condition and this consciousness would
become the basis of timidity. Moreover, it is obvious that normal pupils can set a better standard of speech than can any group of speech defectives. In connection with (2) it may be noted that a special class takes the pupil away from his regular lessons and retardation may result, not only directly from speech defects, but indirectly from absence during periods of instruction in sequential
subjects.
Conclusions like the above led to the organization in Public School T\o. 64 of a class which met for two short periods daily, one in the morning prior to the opening session (8 to 8: 30 a. m.), the other at the close of the session (3 to 3: 30 p. m.). The grade teachers
were urged to co-operate bv attending a session of the class to note the method of speech instructing the pupils, and by making the pupils conform to certain standards in the daily recitation. The speech defectives were told to consult with their regulai class teachers and to indicate their and readiness
willingness
STUTTERING, STAMMERING, AND
LISPING.
99
orally by raising the hand. When reciting, the pupils supposed to stand erect, to take deep breaths, to talk very slowly, and to try to vary the pitch. The teachers were requested To to encourage the pupils to live up to these requirements. in to recite to defectives response questions sharply compel speech put when they are not ready with an answer, frequently throws them iuto such a nervous state that in their attempt to answer, they will relapse into their former habits and nullify the results of
to recite are
instruction.
special
Three forms of exercises afternoon speech classes.
were
employed
in the
morning and
(1) An exercise to build up the weakened respiratory system. For this purpose, use was made of the "Two-minute drill" as given in the city schools. This drill, when properly done, becomes a "minute-and-a-half drill," and consists of deep breathing, armstretching, and forward bending at hips to touch tips of fingers to toes, knee-bending with thumbs locked behind back. Abdominal breathing was taught and a conscious use of this mode of breathing was encouraged. (2) A second exercise for the purpose of recapitulating the steps taken by a young child in acquiring speech. This exercise was based on Wundt's Development of Speech in Children (Entder wicklung Kindersprache). Inarticulate sounds (Schreilaute) gradually lead to the development of articulate sounds, and these in turn lead to the word in the sentence. (3) Ear training. This enables the pupil to hear his own voice and to make an effort to change the tone of his speaking voice from a low monotonous pitch to the modulated speech of a normal child. Inasmuch as speech defectives tend to crowd their
speech
and
ployed
give speech.
of his
faster tempo than the pupil a standard
use a
to
In the first
normal,
by
a
metronome was em-
which to
measure
the
gait
exercise, the effort is made not only to strengthen respiratory and circulatory system, but to impress upon the pupil the fact that proper breathing is a means of overcoming his difficulty. The child is placed on his back and told to inhale and to feel the movement of the belly wall during inhalation In a stutterer, during these and exhalation. respiratory movea marked of the ments, quivering diaphragm may be felt. The can not control his breath in exhalation, nor can he in any pupil way check the quivering of the diaphragm. Moreover, the breath-
the weakened
THE PSYCHOLOGICAL CLINIC.
100
very shallow. The pupil is made to realize these once puts forth a conscious effort to take deeper defects, and breaths to control the exhalation. Constant practice of abdominal breathing causes the spasmodic contractions of the diaphragm The to disappear and enables the pupil to control his breathing.
ing
is
usually
and at
strengthening the diaphragm are used. deeply and then to exhale slowly with the tongue, teeth and lips in the position for pronouncing At the beginning of the work, the length the consonants / or v. of time the child can sustain a tone is usually very short, but he is encouraged to hold a definite tone until perfect control of the diaphragm and larynx is obtained. To a moderate degree, relaxation of the muscles of the larynx is obtained through suggestions as to the poise of the head, absence of collar pressure, front or back, the necessity of talking "up," etc. After telling the pupil that he should have a sense of ease in the throat, breathing exercises are begun. Inhalation is performed very slowly, and exhalation asfollowing exercises The pupil is told
for
to
inhale
Inaudible at first, the sound becomes the sound of ah. in successive drills until finally it is normal. louder and louder The second exercise is then begun. Expiration takes the form of a vowel or a series of vowels, for the defective never sumes
falters on a vowel but always on a consonant. The vowels are sung and sustained at a definite pitch. In the early stages of the work, the duration of this sound varies from five to ten seconds, but after
days' practice, it reaches thirty to fifty seconds. That is during one exhalation, the vocal cords, the glottis and the diaphragm, can be so regulated as to allow the continuation of one sound for half a minute or longer. The exercise is repeated a
few
to say,
with each vowel in turn.
Later the vowels
are
combined with
single consonants, as ha, be, bi, bo, bu, and the series is gone through with one breath. Drills on the more difficult consonants follow, special attention being given to the peculiar difficulties of the individual children. To some g gives the most trouble, to others b, p, 1c, v, etc. Frequently, the initial consonant of the pupil's name is the most difficult. The most difficult consonant,
whatever it may be, is combined with a vowel and a method is devised by which the pupil eventually succeeds in producing it easily. This sound is then combined with another consonant and both are prefixed to vowels, as pra, pre, pri, pro, pru. The third exercise is intended to develop a keen sense of pitch and rhythm. The pupils find little difficulty in repeating the syllables mentioned, especially in a sing-song manner. The introduc-
LISPING.
STUTTERING,
101
speaking serves the very good purpose of develophabit; it produces a change of tone. To break the ing habit of speaking in a low-pitched monotone, all the of the pupils and vowels syllables were at first recited in a sing-song. This led The to the fourth development, namely slower, rhythmic speech. and of the a metronome use slower utterance was taught through intonation was secured through simple rhymes or jingles. Varied through imitation and by the use of charts containing sentences underscored with colored lines suggesting the proper variations of pitch. For example, in the following sentences the intonation is a rising or a falling one, according to the thought expressed in the sentence, and the pupil is taught to indicate the change in tone by raising or lowering the hand. The flag was raised. lion of
melody
in
a new
I walked down the I
jump
steps.
up and down.
Further sentences expressing everyday occurrences were put charts and colored chalk used in marking the vowels, each vowel being marked with a different color. on
Inasmuch
easiest for the pupil to sound, him and enable him to master the encourage In cases where the first word in a senconsonants more easily. tence begins with a consonant, and difficulty is encountered in sounding it, the pupil is taught to introduce a vowel before the For example, in the sentence, "Prince George became consonant.
this device
as
the vowels
are
seems to
King of England," getting a start, he "A
if the initial consonant prevents the pupil from is instructed to read the sentence as though it
Prince George," etc. Having once got under way through the help of such a device, the child encounters no further difficulty provided the respiratory activities are normal. He then practices the initial sound in this connection until he can repeat the sentence with ease. Merely suggesting that the pupil
were
say a word often enables him to do so; he becomes confident, and finds himself trying to verify his growing belief in his
can
ability. Drills in
reading the
vowels in
a sentence are also very helpchart and all the vowels are marked rhyme The pupil then reads the vowels in their characteristic colors. manner in a sing-song according to one of the five types of slowly in 1. The shown consonants are then slipped in and melodies Fig. in a musical tone. The selection entire sentence the read the pupils
ful.
A
is written
on a
THE PSYCHOLOGICAL CLINIC.
102
.o
s:
o
i
FIG. MELODIES. THE FIVE FIG. 1. 1. THE FIVE TYPE TYPE MELODIES.
and
presentation
should
of
reading material
is of
great importance,
and
come as a final step in the treatment. The pupils are taught to be self-critical of their speech. Inappropriate movements, a dull monotonous tone, lack of breath, careless pronunciation or enunciation,?all these faults arouse immediate criticism. Through experience the pupil learns (1) to inhale
until the
belly wall is well extended; (2) to speak slowly and in rhythm; (3) to use a melody; (4) to pay close attention to vowels; (5) to introduce a vowel when in straits. The application of these exercises was fraught with difficulty.
The oral rendition of any selection from the reader seemed to undo all that had been laboriously accomplished. The pupils still lacked power and confidence, and the sight of a reader or any
STUTTERING, STAilOfflZlZVG, AM LISPING.
103
other book made them revert to their old habits. This may have been due to the association of a reader with the unsympathetic audience in the classroom.
For
a
long
time it
was
hard to
develop
type of recitation other than that of question and answer, which would serve for the application of principles already taught; but the imitative instincts of the children suggested a plan which was followed with excellent results. They originated games which a
nothing less than a dramatization of familiar occupations. The One game that proved very effective was called "grocery." and then in a first told could be what grocery store, bought pupils chose a grocer, several clerks, errand boys, and so on. Although it usually required an entire period for the mere organization of
were
the game, it was worth while because it aroused a deep interest in the work. The pupils talked freely and seemed to forget their difficulties. The next two or thrtee periods were spent in buying at
the
taking in
imaginary shop, their
respective
the grocer, his clerks, and the purchasers positions, and conducting the transactions
This type of play became very popular manner. with the children. The transition from this to the dramatization of reading material would not be too difficult. a
realistic
The
course
of work
outlined above tended to make the optimistic. Each felt that through his
briefly
stutterers and stammerers
efforts he had ceased to be a legitimate object for the gibes of his classmates. Even if he had not been entirely cured, at least he felt more confident of his ability to improve, and the attempt had been made to imbue him with the idea that if he faithfully followed up the work he was bound to succeed. own
Lispers include
that group of defective speakers who are certain letters their proper sounds. This inability give due to be the persistence of a habit formed in childhood of may the final dropping syllable or of substituting sounds for those in a word. The latter form of speech is often called required
unable to
"baby-talk"
or
more
due to malformation case of many foreign
properly "infantile late development
or
stammer". It may be of the teeth, and in the
pupils, to a lack of knowledge as to the position of various parts of the articulatory apparatus for the production of certain sounds. Figure 2 shows the position of the tongue, teeth and lips to form such difficult sounds as r, tli, I, s, v and wh. Investigation disclosed the fact that the most difficult sounds were the six just mentioned, and w, z, d and t. The s and 2 are espe-
cially difficult for children who lack the incisor or canine teeth, and they frequently substitute th for s or z. The I, r, t, d, wh and
104
CLINIC. PSYCHOLOGICAL THE
* V FIG. 22
\
wK.
POSITIONS OF THE TONGUE, TEETH TEETH AND LIPS TO FORM THE SIX MOST DIFFICULT SOUNDS.
STUTTERING, STAMMERING,
AND LISPING.
105
usually mispronounced because of inability to place the tongue, teeth and lips in the proper position. In correcting such defects the work is individual. Each is and his difficulties In understood. studied pupil thoroughly done cases where could because of be the condition of the nothing
w
are
teeth,
the children
were
advised to consult
a
dentist and then
the class. The pupil who lisps the I, is brought before mirror and shown how to place his tongue in order to sound the
return to a
letter.
He then
words
containing I,
and
practice reading from a book follows. To make the sound of s, the pupil is told to close his teeth and to touch them lightly with his tongue. After he masters the position he is told to blow his breath between his teeth. The letter r is sinned against chiefly by our foreigners and "baby-talkers". It is especially difficult for Russian Jewish children. The tongue plays an important part in the production of the r sound, being placed opposite the middle of the hard palate and vibrated while its outer edges rub against the hard palate. This sound, like the I, is taught with the aid of a mirror, and also by imitation of another pupil who practices at repeats
numerous
in
the
same
time.
Wh is not
a
difficult sound, except for the for-
is told to protrude his lips in the form of a funnel and to blow out his breath as if trying to cool a spoonful of hot liquid. V, which is sometimes interchanged with w, is made by placing the upper teeth on the lower lip and blowing the breath between the lip and the teeth. Tli, a sound incorrectly
eigner.
The
pupil
many, is made by placing the tip of the tongue between the upper and lower teeth and quickly withdrawing the tongue while allowing the breath to escape between the teeth. The sound may also be made by opening the teeth and forming a slip between the upper teeth and the tongue, but the former method was used because it proved to be easier. T is made by placing the tongue
given by
the upper teeth, d by placing it on the hard palate near the The mouth, of course, is open and the breath is forced out while the tongue is rapidly moved downward. Only two pupils found trouble in forming the cli and sh on
teeth.
which as they gave them, were thick and resembled the On close examination it was found that the steam. of escape mouth was drawn to one side and the sound emitted through an aperture made by the lips and teeth. The defect was overcome
sounds,
by making teeth
as
the
much
pupil control the motion of his lips and possible when producing th'e sounds.
as
close the
THE PSYCHOLOGICAL CLINIC.
106
urgently needed. pupils who are not cured in a reasonable time, because of conditions obviously other than weak mentality. Pedagogical investigation should discover a method for the successful treatment of theste peculiar cases. Statistics should be collected for the purpose of determining the character of the speech of pupils in city schools, so that the investigator of speech defects may give his attention to those groups Further
study of speech defectives Physiological investigation should be made
is
of
which most need his assistance. BIBLIOGRAPHY.
of Phonetics, with directions for the cure of stammering. The Faults of Speech. Xeueste Erfahrungen uber Sprachstorungen; 11)01. Uber die pUdagogische Behandlungen stotternder Kinder in den Schulen; 18S9. Fach, M. Die Behandlung stotternder Schiiler; 1894. Grunbaum. Erklarung des Stotterns. Gutzman, H. Das Stottern, I, II; 1899. Uber die Verhiitung und Heilung der wichtigsten Sprachstorungen; 1898. Die Gesundheitspflege der Spraclie. Hinckley, A. C. A Speech Defect Case Treated at Columbia University. The Psychological Clinic, November 15, 1911. Textbook of Physiology. Howell. Konigs. Die Behandlung stotternder Kinder; 1897. Lewis. Practical Treatment of Stammering and Stuttering; 1902. Stotternde Kinder; 1903. Liebmann. Vorlesungen iiber Sprachstorungen stotternder Kinder; 1898. Uber Sprachstorungen; 1904. Meiinert. Ott. Practical Physiology. Was hat die Scluile zu tun um die Sprechfehler zu bekiiinpfen ? Rogge. 1895. Rouma. EnquOt Scolaire snr les Troubles de la Parole chez Ecoliers Beiges; 1906. Treatment of Stuttering and Stammering; 1907. Scrifture. Treatment of Negligent Speech by the General Practitioner; 1908. Stewart. Manual of Physiology. Stegemann. Heilung d?s Stotterns; 1903. Die Behandlung stammelnder und stotternder SchUlkinder; Stotzner. 1891. Strumpell. Piidagogisclie Pathologie; 1899.
1. Bell. 2. 3. Coen. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 21. 22. 23.
Principles
24. 25. Wundt.
Physiologische Psychologic.
