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Professional History: Intern in Surgery, Johns Hopkins Hospital, Baltimore,
Society Affiliations: Alpha Omega Alpha; American Academy of Facial, Plastic
Honors and Awards: Regent's Award for Superior Teaching, University of
Senator HARKIN. Thank you very much, Dr. Snow. Millions of Americans have different-there's different kinds of hearing loss, and some are affected with a hearing loss that if you are tested in the booth, the sound chamber-I don't know what you call that, but the testing room.
Dr. SNOW. Yes.
Senator HARKIN. Your hearing comes out OK. But if you are in a crowded room or something like that and you are talking to someone, you cannot understand them because of the background noise. I have become aware of this, in fact, having a little bit of a problem with it myself.
But I am just wondering what kind of research is being done in this area. What kind of new hearing aids are being developed? I have heard about some, but I don't really have much knowledge about what is being done in that area.
Dr. SNOW. Yes, sir; we all have trouble hearing in background noise but, of course, this becomes very severe, particularly in those who develop the loss of hearing due to aging, the condition known as presbycusis. And then when one tries to solve the problem of loss of hearing with a hearing aid, just the thing that you point
out, the variation among individuals becomes a very major problem.
One of the hopes is that digital hearing aids will help solve this problem, and we are sponsoring research in which hearing aids are being tested both in quiet and in noise, in which there are men's voices in noise, women's voices in noise and each of those in quiet. Our research in hearing aids really is addressing three major approaches: The amplitude compression, the reduction of noise, and the use of binaural hearing aids, each one fitted differently to each
DIGITAL HEARING AIDS
Part of the problem with the development of digital hearing aids has been that one can work out strategies for different listening circumstances for a given individual, but there is not a great deal of application to other individuals. And that has hampered the production of these for widespread use. What has been worked out in the laboratory for a few subjects is applicable to less than 50 percent of the population that needs a hearing aid, and this makes it a very difficult and complex matter. We are emphasizing the study of the amplified speech signal in a hearing aid and the characteristics of the hearing impairment, trying to match those better than has been done in the past.
Senator HARKIN. One last question. I have a number that I will submit to you in writing.
I am informed that the Defense Department has been doing a lot of classified funding of research and development in certain kinds of equipment, such as eavesdropping equipment, that if available to those working on improving the quality of hearing aids, could lead to some dramatic breakthroughs in quality and sophistication of hearing aids. In other words, the Federal Government has already done some research in another branch on this.
Have you had any discussions with the Department of Defense on this? Are you aware of this?
Dr. SNOW. No; we have not. We are developing the interagency coordinating committee that was authorized by the legislation so that we can be aware as much as possible of what other Government agencies are doing in deafness and other communication disorders. I do not know anything about the classified work.
Senator HARKIN. I also serve on the Armed Services Appropriations Subcommittee, Defense Appropriations. And I am going to get my staff to look into that and try to coordinate with our staff here and with you, and let's see if we can't get you the appropriate classification, whatever you need, to look at this. OK?
Dr. SNOW. Yes, sir.
Senator HARKIN. I am not certain that I am totally aware of it. I have been told about it. I don't have a firsthand knowledge of it myself, but I would like to have you take a look at it and see if there is anything there.
Dr. SNOW. I would be very pleased to do so.
QUESTIONS SUBMITTED BY THE SUBCOMMITTEE
Senator HARKIN. Thank you very much. There will be some additional questions which will be submitted for your response in the record.
[The following questions were not asked at the hearing, but were submitted to the Institute for response subsequent to the hearing:]
QUESTIONS SUBMITTED BY THE SUBCOMMITTEE
Question. We've talked in the past about the need to bring the science that supports deafness and communication disorders up to par with the science that supports and investigates other categories of disease. One of the major problems in this field has been the lack of trained molecular biologists and other scientists with state-ofthe-art specialties. I was pleased to see that we were able to increase the number of individuals trained by your Institute from 112 to 149 between 1990 and 1991. Unfortunately, your 1992 request would only maintain the 149 trainees. In your professional judgment, how many training slots should be supported in 1992 to help bring the science of deafness and communication disorders up to par with other fields of science?
Answer: In my professional judgment 208 training slots should be supported in 1992.
Question. If the Congress were able to provide funding to your Institute above the 1992 requested level, what relative priority would you assign to providing more funding for training?
Answer. Training is of critical importance. It is the foundation upon which excellence in research is built. Training and career development remain a high priority for the NIDCD. We are very pleased that the National Multipurpose Research and Training Centers are offering continuing education and research training to physicians.
Question. Dr. Snow, I understand that you made a proposal to NIH management that would provide a supplement to research project grants to permit additional training to take place in the context of work being done on research project grants. This would be a new mechanism, a new way of attempting to train more individuals. What is the status of this proposal at NIH and how much do you estimate it would cost to add this training component to your research project grants in FY 1992?
Answer. We have received tentative approval from the NIH for our "Mentor" program and are now working on the final details of the proposal. I believe this program can offer our investigators an excellent opportunity to move into the forefront of biomedical research by learning research techniques in molecular biology, thereby giving them the tools needed to provide us with answers in such difficult areas as hereditary deafness and the regeneration of hair cells. We estimate that this initiative would cost $4,350,000 in FY 1992 and could be accommodated within our overall request if deemed a priority. In FY 1992 the second year costs of the FY 1991 awards would be supported; and approximately twice as many new awards would be made as in FY 1991.
Question. How much would it cost to add this component to your research project grants in FY 1991 and is this something that the Director's Discretionary Fund can be used for?
Answer. The "Mentor" program would cost approximately $1,350,000 in FY 1991. We anticipate making awards in the third or fourth quarter of FY 1991. We will propose it to the NIH as a possible use of the NIH Directors' Discretionary Fund.
Question. In January of 1989, the Institute developed a research agenda to cover all seven areas of the Institute; smell, taste, hearing, balance, language, voice and speech. This year, I understand, you have an effort underway to update the National Strategic Research Plan for language and balance and that with recurring updates the entire plan will be updated every 3 years. Why did you choose language and balance to begin your update what areas will be updated in FY 1992?
Answer. The National Deafness and Other Communication Disorders Advisory Board unanimously agreed to update two of the six research sections of the National Strategic Research Plan each year. The National Advisory Board selected the Balance and Vestibular Systems and the Language Sections for updating in 1990-1991, the Hearing and the Voice Sections in 1991-1992, and the Smell and Taste and the Speech Sections in 1992-1993.
BRAIN IMPLANTS SIMILAR TO COCHLEAR IMPLANTS
Question. Dr. Snow, we have talked about cochlear implants and we have a very excellent program at the University of Iowa that is continuing research on cochlear implant development. I understand that there is research underway to actually implant something in the brain to stimulate areas of the brain that are related to hearing, if the nerve cells are dead within the ear. Are animal experiments underway with regard to such brain implants?
Answer. Research is indeed under way to determine the optimum design, effectiveness and potential side effects of an auditory brainstem implant (ABI). This electric prosthesis, similar to the more familiar cochlear implant, is positioned in the lateral recess of the 4th ventricle of the lower brainstem, abutting the dorsal cochlear nucleus.
Question. Could you update us on the prospects for such
Answer. Its use is indicated in cases where the auditory nerve has been damaged by the presence of tumors, as in neurofibromatosis type 2 (NF 2) or severed by skull fracture following head injury-situations in which a cochlear implant could be useless. Animal studies have been conducted to determine the optimum electrode design and location, safety of long-term electric stimulation to brain structures, and effectiveness in producing awareness of sound.
Question. Do you believe they are feasible in the long run for human beings?
Answer. More recently, a prototype device has been implanted in 19 patients with bilateral hearing impairment due to NF 2. ability to understand speech with the ABI is, on the average,