of the committee, it would be appreciated if each member of the panel will stand in turn and give a bit of his background and his present position. I notice that several of the witnesses are familiar to the committee, having testified earlier in connection with other disease entities. We welcome them back.

At this point, I would like the prepared agenda and the list of witnesses to be made a part of the official record of this hearing. (The matter referred to is as follows:)

HEARING DEFECTS AGENDA FOR DISCUSSION, OCTOBER 9, 1953

I. Opening remarks, chairman, discussion leader.

II. What is the importance of deafness and other hearing disorders as health problems in America today?

III. What are the various kinds of hearing defects? How are they characterized medically?

IV. What is the current status of knowledge relating to these disorders

V. What are the major private and public efforts in the deafness field?
VI. What are the promising lines of research?

VII. What are the medical-care problems in the treatment of deafness?
VIII. What can be done to prevent deafness?

IX. What is the relation to deafness of such disorders as otosclerosis?
Ménière's disease? Motion sickness?

X. What are some of the needs in the field? Is there anything not being done that should be done in order to facilitate progress against these diseases?

PARTICIPANTS

Dr. William Hardy, director of the Johns Hopkins Hospital Hearing and Speech Center, Baltimore, Md.

Dr. Aram Glorig, Head, Audiology and Speech Correction Center, Walter Reed Army Hospital, Washington, D. C.

Dr. Leonard M. Elstad, president, Gallaudet College.

Dr. Pearce Bailey, Dr. Seymour Kety, Dr. Fred Stone, National Institute of Neurological Diseases and Blindness, Public Health Service.

Mr. HESELTON. Will you please proceed, Dr. Hardy. Then after the introductions, you may go right ahead with the discussion in any way that you see fit.

STATEMENT OF DR. WILLIAM HARDY, DIRECTOR OF THE JOHNS HOPKINS HOSPITAL HEARING AND SPEECH CENTER, BALTIMORE, MD.

Dr. HARDY. Thank you, Mr. Chairman.

My name is William Hardy. I am director of the Johns Hopkins Hospital Hearing and Speech Center, and am on the faculty of the School of Medicine and Hygiene. During the war I had the honor to serve in a capacity with the Navy directly related to these problems, as have some other members of the panel.

I will ask the other members of the panel to identify themselves in order down the line.

Dr. BAILEY. My name is Pearce Bailey, a physician, presently Director of the National Institute of Neurological Diseases and Blindness; a professor of clinical neurology at Georgetown University; and past president of the American Academy of Neurology.

Dr. STONE. My name is F. L. Stone. I am chief, extramural programs, National Institute of Neurological Diseases and Blindness, National Institutes of Health.

Dr. ELSTAD. I am Leonard M. Elstad, president of Gallaudet College, Washington, D. C., and executive officer of the Institute for the Deaf. I have been working with deaf children for 30 years.

Dr. GLORIG. My name is Aram Glorig. At present I am chief of the Army Audiology and Speech Correction Center at Walter Reed Army Hospital, which takes care of all hearing problems of the Army and Air Force. I am a member of several societies which have to do with hearing and its ramifications.

Dr. HARDY. I would like to make a short statement first and then call on Dr. Glorig to summarize his ideas. It will be necessary, perhaps, for him to leave early.

The approach to the general problem of hearing disorders spreads to a set of definitions and a review of facts as they exist in general. The term "deafness" has been known and used in our language for many years in a fashion that is too hard to define in medical terms in case finding, diagnosis, therapy, into the problems of rehabilitation, and education.

Dr. Elstad is most experienced in the training of deaf persons. A deaf person, by definition, is one whose hearing is so nonfunctional that he has had to develop language and communication by nonverbal or nonoral means. The hearing mechanism serves as the base for our intake from our environment for the development of speech in a child.

The other level is the group known as the hard of hearing, where there is a hearing disorder but not so extensive that it interferes completely with symbols in ordinary conversation. The differentiation between those two groups is difficult to make clear.

The general problem of hearing defects and hearing disorders continues to be widely misunderstood and misapprehended, perhaps largely because a hearing disorder does not show as a human disability; it does not have a mortality rate; the fear of continued welfare does not show. What shows is the effect of noncommunication or interference with communication in terms of some of the psychological aspects of being able to converse freely, and that results in a real disability.

There are about 200,000 to 250,000 persons who can be called deaf in the sense I have just defined. They have been treated as deaf people, pretty largely employing nonoral or nonverbal communicative means.

There are probably somewhere between 15 and 20 million persons in this country with some aspect or other of hearing disorder as a general broad category, sometimes involving one ear and sometimes both ears.

There are probably somewhere around 12 million persons who are disabled to the extent of interference with their daily occupations or potential occupations and normal social existence to the extent of needing to use a hearing aid as a means of helping them to communicate.

As we look at the general problem, first from a medical and later from a rehabilitative point of view, there are a good many ways of approaching an analysis. I can speak better, perhaps, as a person who sees the problem at a clinical level. There are four categories:

In the first category, there is the very young child, where the cause of defective hearing may be prenatal, or it may be related to certain natal or immediately postnatal occurrences, many of which center around the field of obstetrics or postnatal infections. In our clinical load, which is large, are tiny infants and preschool children. We estimate that about 40 percent of the children we see who are badly disabled from very early times, immediately following birth or prenatal, have preventable disabilities in medical terms with further knowledge and adequate control of, say, birth circumstances. With the improvement of clinical methods and the further knowledge needed of the basic operation of the hearing mechanism, about 40 percent of the number of cases in early childhood involving serious hearing impairment can be wiped out.

Among school children ranging in age from approximately 6 to 14, a conservative estimate, based on a highly adequate survey system, is 5 percent of hearing disability as a general national figure. For various reasons, a large percentage of that is remediable.

In the adults up roughly to middle age, however, if you wish to define that, I think it is a safe generalization to say about 50 percent of the cases of hearing disorders in adulthood could be prevented by adequate and early controls, because many of them have their onset in childhood.

In the fourth category there is a field that must be approached with complete humility, and that is the whole area of the hearing disorders that occur with old age. I think it is safe to say that nobody in this country or in the world can at present analyze the physiology of old age that results in the breaking down of hearing as one gets older.

There are many details I am sure you will have questions about as to the known hearing impairments and the known means of remedying them. We can think and talk in about three major categories.

The first category has to do with prevention as a general, broad approach to a severely disabling problem or trouble.

The second has to do with medical and surgical therapy designed to cure, mitigate, or reverse symptoms.

The third category is in the general realm of rehabilitation or special training necessary to be carried out when one is faced with permanent hearing impairment which has not been prevented and which cannot be cured.

I would like to comment on one more figure which has been derived by as careful a study as yet made in the field, that at the present time approximately 300 million man-hours of productive effort are lost per annum from causes directly traceable to hearing disorders. Now I would like your indulgence to hear Dr. Glorig.

Mr. HESELTON. Are there any questions?

Mr. THORNBERRY. Mr. Chairman, I have a few questions, but I thought I would wait until Dr. Glorig got through. Dr. Hardy, let me ask you this: In what field or category do you put those people who lose their hearing at an early age? My parents are both deaf, and I have been associated with deaf people all my life, and most of those I know have lost their hearing in infancy or at birth; at least, that was their history. In what category do you put those people?

Dr. HARDY. I meant to indicate, though perhaps I did not do so clearly, that many of those cases can be categorized under prevention, and the rest have to go under rehabilitation and training.

Mr. THORNBERRY. What is the cause? Does the loss of hearing in most of those cases occur at birth or just after birth? In the history of deafness, do most cases occur in infancy?

Dr. HARDY. About 40 percent of the clinical cases involve a hearing disorder that is prenatal, natal, or immediately postnatal, and about 40 percent are medically preventable.

Mr. THORNBERRY. What percentage did you say are medically preventable?

Dr. HARDY. Forty percent. For instance, the so-called RH factor, neonatal, involves some broad changes in the blood system which, for some reason take their toll, among other things, in the hearing mechanism. That is preventable more now than it used to be. That has not been recognized as an entity more than 13 years now, and the field is slow in going through.

Among a large group of schoolchildren, we find about two-thirds of the problem in total are postnatal, coming from disease entities that are quite well known. Most virus diseases can cause hearing impairment. When you look back over the record of the years, when it was unusual if not impossible to carry out presently known diagnostic procedures, the temptation was to call it congenital deafness. We are beginning to find out now that that was not true. Some of the problems do date from or predate birth, but many others normally accrue from well-known diseases in infancy.

For instance, the incidence of children who suffer severe impairment from measles is relatively little. No doubt there are those who suffer that impairment by a nerve-type destruction of the hearing mechanism and that is a kind of problem that simply is present. When the nerve structure is damaged there is nothing to do about it. Mr. THORNBERRY. That is the type that results from measles? Dr. HARDY. Yes. That is one disease and, of course, there are other viruses.

Mr. THORNBERRY. I have a number of questions, but you indicated Dr. Glorig might want to leave early and, rather than hold him up, I will let him go ahead. There are a number of questions in this field in which I am personally interested.

One question which I might ask at this time is this: Doctor, in my contacts with the deaf I think there has always been the feeling that the cause of deafness is largely, as he termed it a while ago, due to being born deaf. My experience is that generally deaf people feel they were born that way.

Dr. ELSTAD. When you take into consideration the deaf as a group, about 30 percent are known to have been born deaf.

Dr. HARDY. That fits the picture very closely.

Mr. THORNBERRY. Is that what you think, too, Dr. Hardy?

Dr. HARDY. That is about the general pattern.

Mr. HESELTON. I take it that someone will give us information as to the type of research that has been done and what can be done. Dr. HARDY. Yes, sir. We will try to get to that.

Mr. HESELTON. Will you please proceed?

STATEMENT OF DR. ARAM GLORIG, HEAD, AUDIOLOGY AND SPEECH CORRECTION CENTER, WALTER REED ARMY HOSPITAL, WASHINGTON, D. C.

Dr. GLORIG. First, may I explain why I have to leave early? There is a large national committee meeting which is to be held today to discuss this very problem in relation to industry and in the Army, and I am a member of that committee and I should get back as soon as I can. I apologize for having to do so.

To go on a little bit into the problem of hearing losses, certain school surveys indicate that about 5 percent of the children are found to have hearing losses which need audiological attention and that means hearing losses which may be prevented provided they get this audiological attention.

A little more of the problem is represented by the military and veterans' problem. For example, the Veterans' Administration is paying 10-percent disabilities and in some instances a great deal more to about 90,000 men at the present time for hearing losses sustained during World War II. This amounts to quite a financial problem when you break it down a little. That is in compensation alone. Now, for hearing aids issued to veterans, since 1949 there have been about 40,000 hearing aids issued at a cost of about $120 each, and when you figure that out it comes to quite a bit of money also. This has nothing to say about rehabilitation and reissue and batteries. The battery problem alone amounts to somewhere near one-half to threequarters of a million dollars a year to supply batteries for these individuals who have hearing losses and who are using hearing aids.

The Army in the last few years and part of 1945, 1946, and I believe back as far as 1944 rehabilitated 12,000 individuals who sustained hearing losses in the Army, and this is in addition to those which I spoke about in the Veterans' Administration. The Army at the present time, during a so-called peace regime, is rehabilitating about 1,200 men a year. These are both from the Army and the Air Force. The Navy figure is not that large. We issue some 600 hearing aids per year at the center, and to give you a little bit of an insight into what this means to the Army at the present time, we have about 4,500 or 5,000 men in the armed services who are using hearing aids. The rehabilitation has been so thoroughly done that 98 percent of the men we have at the center go back to military duty. Our only restriction is that they not be put in an actual combat situation. I am merely mentioning this to show you that rehabilitation can prevent some of this 300 million man-hour loss, providing we do something about getting it done among the civilian population.

The problems in industry, which are just recently being recognized, although it has been present since 1885, when hearing losses were referred to as "boilermaker's deafness," are now being studied. At the present time it is coming into the limelight due to the number of compensation payments which have come about and the potential which is growing every day.

Mr. HESELTON. What does that amount to?

Dr. GLORIG. It varies from $4 million to $7 million in deafness caused by industry at the present time.

Another point of the problem would be that when men are tested prior to entering into an industrial situation which is a noisy industry,