We studied on effects and using methods of hearing aid and articulation disorders in 15 pupils who are in special class for hearing loss in Osaka. They were tested by pure tone and speech audiometry in free field. The following results were obtained. 1) All cases acquired better hearing at pure tone, especially 1000-2000cps, with hearing aid. 2) The results of speech audiometry indicated the effects of hearing aid. We found out that articulation scores were changed with hearing aid. 3) They were wearing their hearing aids effectivelly. 4) We observed on the articulation disorders with relation to hearing.
For the purpose of determining standard use of hearing aids by young children, a series of investigations regarding the models, the range of frequency response characteristics and the volume control of hearing aids were conducted on 22 sensorineural hearing impaired children who were skilful user of hearing aids and whose age ranged from eight to fourteen years. The results obtained are briefly summarized in the following. 1. If the average hearing levels in speech range are not worse than 80dB, hearing aids in Japanese make (R Co.) may be helpful, but U. S. make (Z Co.) are more helpful for those children. 2. Type of broad frequency response characteristics (300-4000cps) is more suitable than narrow (500-4000cps) for those hearing impaired children. 3. In respect of volume control, comfortable level setting for normal ear is suitable even to those with impaired hearing. 4. To obtain good speech discrimination by hearing aid, input sound level must be set as high as 70-80dB (P0=0.000204 dyne/cm2).
In 1966, we have set up the Auditory Training Class for hearing impaired children. The goals of this class are as follows; 1. To teach the child to tolerate headphones. 2. To help the child to discover that listening to sound is pleasant. 3. To show him how to respond consistantly to the presence and absence of sound. 4. To secure a more complete hearing test. 5. To select a proper hearing aid for the child, and to help him make optimum use of amplified sound. 6. To give the parents as much information as possible regarding the nature and extent of the child's hearing loss. Since July 1966, through June 1967, we have finished adaptation of hearing aid for 51 young hearing impaired children. Out of them, 42 started to wear hearing aid every waking hour by the end of our auditory training. Even they were very young, they will start to were hearing aid if we give them correct and reasonable auditory training for hearing aid adaptation. Also our procedure and technique were mentioned in this paper, and it was emphasized that in order to obtain maximum benefit from hearing aid, the hearing impaired children should be fitted a hearing aid as soon as possible after the diagnosis is made.
The author reported a new teaching method for hard-of-hearing children. Teachers voice are transmitted through a wireless microphone to the receiver of FM transistor radio weared by the hard-of-hearing child. As a point of advantage of this method the child experiences lesser fatigue comparing with the hearing aid, especially in the noisy class room of the lower elementary grades. This is a convenient method which can be employed in the ordinary school in the district where neither day nor residential schools for hard-of-hearing children are founded.
The audiograms of 52 deaf children who had used hearing aids for a long period since they had been very young, were reviewed. The audiograms of two boys showed the increasing of their hearing losses of the ears on that sides hearing aids had been weared. The audiograms of two girls and a boy had not significantly changed on the ears which hearing aids had on, beside the audiograms of the other ears without aid moved up. This fact may be considered as that the no-changed sides might move up if the aids were not weared. However an audiogrm indicates increasing of losses nevertheless the aid was not used, beside the audiogram of another ear with aid indicats decreasing of losses. So it is hard to say these five cases, increasing losses, are because of the use of hearing-aids. The audiograms of both ears of 6 children have moved to upside even aids have been weared only one side. This can be understood the result of auditory training.
It seems that auditory training of children who has 80dB hearing loss is very difficult. But in order to habilitate their language and speech, it is a distinctly advantageous approach to use their residual hearing through hearing aid. This study attempted to investigate how children who has 80dB hearing loss are able to hear sounds and discriminate speech sounds. Five children who has flat type of hearing curve, a verage 80dB, congenital hearing loss were chosen as samples. The summary in this study is as follows. 1) Although their score are very poor, they can discriminate simple speech sounds by using powerfully amplified hearing aids. 2) Their unaided and aided speech reception threshold shorned almost the same level with their unaided average and aided hearing loss for pure tone. 3) In dealing with discrimination for vowel sounds, discrimination score had the tendency to become worse in “a, o, i, u, e” order. They discriminate “u” sounds very hardly and did not discriminate “e” sounds at all. 4) Correct and effective hearing aid and volume control should be considered.
The authors applied the acoupedic approach to forty children who suffered from sensory neural hearing loss for three years. The methods, the results and added some views are summarized as follows. 1. Most children had visited two or three hospitals before they came to the clinic at the center. But it was only 27.5% of the children who had been recommended to use the hearing aids. And also, only 15% of them was using the hearing aids in their daily life. The authors strongly stress the need of increasing the number of speech and hearing clinics where handicapped children can receive necessary habilitation program. 2. The retardation in language developement was found in all of them. The retardation is larger in the children of older age, and the early finding and the early training are considered to be the most important. 3. The habilitation program at our center consists of the acoupedic approach and the well planned listning program. The children were trained and checked at the clinic once a week and the families were asked to perform the listning program intensively at home. The later is especially important in order to cover the lack of the time of the formal training. This combined use of the two methods has made it possible to send the hard of hearing children up to 70dB to the ordinary school in three years. The authors are convinced that the combined method could be worth to apply to the severely hard of hearing children beyond 70dB in their early life. 4. The authors are planning to produce sufficient number of teachingtapes and to develop easy-to-use materials inorder to efficiate the auditory training at home.
Sixteen hard of hearing children of two to four years old, whose hearing losses are between 50 to 85 dB, were educated by Acoupedic Approach. Six and ten of them were treated during 1964 and during 1965-1967 respectively. The children of 1964 were encouraged to speak spontaneously even in early days of the education, whereas for the children of 1965-1967 the educational program for their spontaneous language expression was postponed to the time after the program for recognition and discrimination of sounds was treated enough. The results are as follows: (1) The total number of words spontaneously used decreases according to the severity of hearing impairment. This result is confirmed with both groups of the subjects. (2) With the progress of the education, the total number of words increases more rapidly for the children of 1964 than that of the children of 1965-1967 does. When the spontaneous expression is encouraged, the development of language is accelerated as far as in the total number of words in vocabularies. However, the analysis of classification of words used by both groups reveals that their vocabularies consist of much of nouns and less of verbs compared with that of a normal child. This result seems to lead a further improvement of the educational method in future. (3) The order of occurence of words used by the children tends to be analogous to that of normal children.
Intelligibilities of speech sounds were evaluated for 4 years in 29 hard of hearing children with 30-70 dB hearing loss, being provided with speech habilitation, including auditory training, in the special class for the hearing handicapped children. They were 6-11 years of age in the first year. The following results were obtained; 1. In any age group, their intelligibility scores of speech sounds were increased more distinctly in the first year than in later years. 2. Correlation between their intelligibilities of speech sounds and thir thresholds of hearing showed a yearly decrease. 3. Intelligibility scores such as “vowels”, “k”, “t”, “h”, “p”, “F”, “j”, “w”, “n”, “m”, etc. reached more than 90 per cent in the last year, but those of fricatives and affricatives such as “f”, “s”, “z”, “dz”, etc. remained near 60 per cent. 4. Errors of articulation changed mainly as follows: 1). Omission→normal: 25.2% of total omissions in the first year. 2). Replacement→normal: 34.5% 3). Replacement→near normal→normal: 11.5% 4). Distortion→normal: 32.8% 5). Distortion→near normal→normal: 16.0% 6). Near normal→normal: 53.6%
We examined the hearingloss of 31 cases in 4-7 years old children who had congenital malformation of the external ear. In case of congenital malformation of bilateral. external ears, two cases were diagnosed as sensorineural hypoacusis and the others conductive hypoacusis. The hearingloss of the bilateral microtia was found to be more severe than that of the unilateral microtia combined no other deformity. Characteristically, 6 out of 31 cases were seemed to be concerned with salidmide. Regarding to language development, children showed congenital conductive hypoacusis were favourable in development of vocabulary, articulation, language comprehension, discrimination score and special training, in comparison with children showed sensorineural hypoacusis with the same grade of hearingloss as above conductive hypoacusis.