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INTRODUCTION
Hearing aids are the most effective therapeutic device
available for most hard of hearing people. Except for those relatively few individuals whose hearing loss can be corrected
medically or surgically, hearing aids are the only therapy which directly addresses the root cause of their difficulty: the
hearing loss itself. Properly fitted and used, hearing aids are able to enhance the lives and well being of hard of hearing
people.
Hearing loss can affect an individual's quality of life and ability to function in our society. Because it
hinders the most basic of all human attributes - interpersonal communication - the consequences of a hearing loss ripple outward
and affect all of those who come in contact with a hearing-impaired person. While a "patient" may have difficulty hearing,
it is society, in its broadest aspect that has the hearing "problem."
THE EFFECTS OF A HEARING LOSS
Observations
Anyone who has a significant hearing loss can testify how the hearing impairment has affected his or her life. The consequences
of the hearing loss can permeate and distort the entire fabric of a person's life, from the social, vocational and cultural
activities that one has engaged in, the ongoing relationships with friends and family that have developed, to the view of
oneself that has evolved over a lifetime. The hearing loss challenges and creates obstacles to the realization of these capacities,
attitudes and habits, leaving one less able to cope with the demands of a modern society.
Hard of hearing people commonly
withdraw, or feel isolated in, any social situation taking place under noisy circumstances. The difficulty in understanding
the conversation at such times, the effort to make sense of the acoustic fragments which are perceived, is a frustrating,
fatiguing, and anxiety producing exercise, often leading to irrational anger directed both inward and outward. A hearing loss,
even a moderate one, can isolate hard of hearing people from the mainstream culture and severely restrict the quality of their
lives.
What makes the situation worse are the common misconceptions about hearing loss held by the general public.
Unlike deaf people, the listening behavior of hard of hearing people is often erratic - sometimes they can hear and sometimes
they can't - and normal hearing people may ascribe the communication breakdowns to either a willful choice by the hard of
hearing person, or to a developing neurological or personality problem. The impact of external conditions (noise, reverberation,
distance, poor speaker articulation, etc.) are much greater, and more unpredictable, upon hard of hearing people than upon
those with normal hearing (Ross, l992). The communication breakdowns that occur are, therefore, often thought to reflect a
cognitive disorder ("she's getting old, you know"), deliberate inattention ("she can hear when she wants to") or low regard
for the conversational partner ("he just ignored me!"). The consequences of this misapprehension is that hard of hearing people
are often ridiculed, objects of derision, demeaning jokes and comments or, what is perhaps even worse, simply ignored.
Research
The effect of hearing losses on speech perception is a well-established area of clinical investigation, with self-evident
results: a hearing loss will reduce a person's ability to comprehend speech (Nabelek and Nabelek, l994). Generally, the greater
the hearing loss, the larger its impact upon speech comprehension. This average relationship is somewhat complicated by a
person's audiometric configuration, the etiology and nature of the hearing loss and whether the hearing loss was incurred
early or late in life (Bergman, l980).
What is not sufficiently appreciated is that the emotional and psycho-social
state of hard of hearing people may also be affected by the erratic and disrupted communication patterns caused by a hearing
loss (Weinstein and Ventry, l982; Thomas, l984; Knutson and Lansing, 1990). We know, for example, that people with acquired
hearing loss manifest psychological disturbances at four times the rate exhibited by normal hearing people (Thomas, l984).
There is also good evidence that an adventitious hearing impairment can influence and compound the total behavioral picture
of patients with Alzheimers and other cognitive disorders (Dye & Peak, l983; Mulrow, et al. l990; Ulmann, Larson, Rees,
Koepsel, & Duckart, l989), affecting memory, mood, alertness, and general ability to cope, beyond that expected of the
cognitive problems in the absence of a hearing loss. In several studies, Bess and his colleagues (l989, l991) demonstrated
that the total functional impact of a hearing loss (greater than 41 dB) is similar to those exhibited by people with major
medical conditions (e.g. heart transplant recipients, pulmonary disease, etc.) Clearly, as has been stated above, while a
hearing loss may be invisible, its effects are certainly not.
Effect of Hearing Aid "Treatment"
Fortunately, the
handicap produced by a hearing loss can be reduced by the use of hearing aids (and other types of assistive listening devices).
By its very nature, that is by amplifying speech and other sounds, a hearing aid will improve communication capacity to some
degree for most hard of hearing people. The improvement in communication skills wrought by hearing aid "treatment" can also
enhance psycho-social and neurosensory functioning (Weinstein, l993; Dye and Peak, l983; Abrams, Hnath-Chisolm, Guerreiero,
& Ritterman, 1992). Study after study has shown that the handicapping effects of a hearing loss are reduced after a hearing
aid is worn, and that this functional improvement remains long after the initial fitting. What this accumulating body of evidence
demonstrates is that hearing aids are an effective and indispensable therapeutic device for the vast majority of people with
hearing losses.
ISSUES IN HEARING AID MANAGEMENT
Qualification of the Dispenser
Hearing aids are highly
sophisticated devices, reflecting a blending of advances in computer, communication, and electronic technology, with added
features and developments appearing at a rapidly increasing rate.The body of knowledge and skills required to validly administer
pre and post-hearing aid fitting evaluations have also been increasing at a rapid rate. Clinical interview and counseling
techniques are now seen as indispensable components of the hearing aid fitting process. Follow-up procedures for many clients
require conducting various kinds of aural rehabilitation procedures (communication training, selection of specific assistive
devices, coping and conversational strategies, etc.). What the foregoing implies is that the highest order of skills and training
are necessary for those professionals who engage in the practice of selecting and fitting hearing aids.
It follows
that hearing aids be dispensed only by qualified health-care professionals. At present, certified audiologists are the only
group with the demonstrated academic and clinical training to conduct and interpret the necessary battery of tests required
for hearing aid selection, fitting, and aural rehabilitation follow-up. Obviously, there are many competent hearing aid dispensers
who are not certified audiologists and certainly not every certified audiologist is competent. Nevertheless, on balance, it
appears that the interests of hearing-impaired consumers can best be met by requiring hearing aid dispensers to meet the highest
academic and clinical standards. In this regard, requiring a professional doctorate in Audiology as the entry practioner degree
will help ensure that these high standards are met.
Return Policies
Different states, different hearing aid manufacturers,
and different dispensers have different return policies. Typically, when such a policy exists, it must be exercised within
30 days. For a new hearing aid user, 30 days is not enough to determine whether the cost/benefit ratio of hearing aids justifies
the expense. There is some very good research and clinical evidence that it takes time for people "adapt" to the new pattern
of sound provided by a hearing aid. In several studies, Gatehouse (1992, 1993) found that speech perception scores can continue
to incresase up to 16 weeks post hearing aid fitting in ears fit with a theoretically appropriate amplification pattern. The
difference between this pattern and a less appropriate one was not apparent during the first few testing sessions. This basic
finding has recently been supported and extended to the use of multi-band compression amplification systems (Yund & Buckles,
l995), and even when controlled for volume control setting and evaluated both objectively and subjectively (Horwitz and Turner,
l995).
This research calls into question single-session methods of hearing aid evaluations. In other words, we cannot
observe the full benefit of a hearing aid until at least several months post-hearing aid fitting and we cannot determine in
one or two sessions which amplification pattern would, eventually, provide the most benefit. Furthermore, as necessary to
the hearing aid fitting process as objective testing procedures are, no tests can substitute for a real-life trial period.
The varied acoustical environments and communication demands upon a specific person cannot be - completely - replicated in
the clinic setting. Real-life trials are crucial and must be provided; the questions here are how long should the trials be,
and what kind of interim follow-ups should be made by the hearing aid dispenser? What the research suggests is that a minimum
of a 60-day post-purchase trial period is necessary. If a user decides to return the hearing aid within the 60-day period,
he or she should pay a reasonable rental charge and reimburse the dispenser for cost of earmolds, batteries, etc. Given this
extended trial period, it is in the interests of both the user and the fitter to make every effort to ensure that the trial
is successful which implies the necessity of careful follow-up programs.
Follow-up Programs
The provision and
the cost of hearing aids need to be viewed as part of a package deal. Hearing aids cannot be dispensed casually; a great deal
of reeducation (of residual hearing and attitudes), information (about hearing loss, assistive devices, expectations, coping
strategies, etc.) and training (speechreading and auditory training) is often required if the hearing-impaired person is to
receive the most, or any, benefit from hearing aids. We all know of the many aids that wind up in dresser drawers rather than
ears! Every time this occurs, not only has society and the individual wasted scant resources, but hearing assistance help
was denied the hearing-impaired person.
For all hearing aid users, but new ones in particular, individual and group hearing
aid orientation programs should be routinely scheduled during the trial period. A group program lends itself to not only to
efficient information dissemination but permits the emergence of group dynamics that can add an important psychosocial dimension
to effective use of amplification and self-acceptance. Research on such programs have convincingly demonstrated their effectiveness
(Ross, l987). They should be seen as an integral component of the hearing aid dispensing process, as important for many patients
as the hearing aids themselves. The same logic that supports the need, and support, for other types of non-medical therapies,
(Speech-Language, Psychological, Physical, and Occupational) applies to Hearing Disorders as well. The consequences of a hearing
loss can be no less debilitating than those occurring with linguistic, psychological, and physical conditions, and the willingness
of society to support therapy to ameliorate the effects of these other conditions should also be extended to people with hearing
losses.
The Cost of Hearing Aids
Hearing aids range in price from about $500.00 to $3000.00, with an average cost
of over $800.00 (Kochkin, l993). The high cost of hearing aids are a recurring theme in the reasons given why they are not
used by many more people who are potential beneficiaries. Some of the cost is unavoidable; it takes a great deal of time to
do the preliminary audiometric testing, select and fit the hearing aid(s), and conduct the necessary follow-up appointments.
Some other portion of the cost can undoubtedly be ascribed to time-consuming and inefficient marketing efforts, a haphazard
referral process, non-standardized testing techniques, and an inadequate utilization of media (arranging home viewing of informational
video tapes, for example). Much of this portion of the cost is inherent in the current system of independent practitioners
where the economies of scale cannot be applied. The cost quoted above underestimates by about half what hearing aids may actually
cost a consumer. That is, the actual cost would be closer to $1,600.00 than $800.00 if binaural and not monaural hearing aid
were routinely fitted.
Binaural Hearing Aids
In the absence of clinical indications or personal preferences to
the contrary, binaural fitting should be seen as the routine practice in dispensing hearing aids. There are two basic reasons
for this recommendation. One is the proven superiority of two ears over one for most hard of hearing people a long-term professional
issue to which a consensus has finally been reached. The other reason follows from a relatively recent concern of audiological
investigation, that of adult onset auditory sensory deprivation. Briefly what this body of research has been showing is that
in cases of monaural hearing aid fitting, the speech perception skills in the unaided ear begin to diminish (Silman, S., Silverman,
C.A., Emmer, M. B. & Gelfand. S. A., l992). Furthermore, if the deprivation is long enough (presently undefined), then
not only is recovery unlikely if hearing aids are subsequently worn, but binaural advantages may never be attainable (Hurley,
l993; Gelfand, S.A. l995). Given the quality of the evidence for this phenomenon, any dispenser that fits a monaural hearing
aid may be vulnerable for a malpractice suit. Certainly, the final decision regarding whether one or two hearing aids are
to be used rests with the hearing aid user, or the parents of a hearing-impaired child; the dispenser, however, is ethically
obliged to inform prospective hearing aid users of the possible implications of their decision.
Types, Performance,
and Expectations with Hearing Aids
The emphasis in current hearing aid fittings, and future hearing aid design, must focus
on performance and not cosmetics. As hearing aid industry leaders have themselves pointed out, the stress on "invisible" hearing
aids is counterproductive (Kochkin, l993). This focus simply reinforces the stigma view of hearing loss held by many hearing-impaired
people, leading to a refusal to acknowledge the reality of their own hearing condition. We have no objection to size reductions
as such - indeed, for some people, there is acoustic merit in fitting the entire hearing aid in the ear canal - as long as
the size reduction is not accomplished by compromising quality (Preves, l987; Ross and Madell, l989; Killion, l993). For example,
one major reason why most hearing aids have either no or inadequate telecoils is because of size constraints. Telephone coils
(the "T" switch) is an effective assistive listening device, which can be profitably utilized in many situations other than
with telephones.
Elderly people comprise a large segment of potential hearing aid candidates. Often, because of problems
with vision and finger dexterity, they have great difficulty in managing the controls and changing batteries. Hearing aids
with remote control units can help such people, but these aids are more expensive than the average aid. There is still a need
for high quality body worn hearing aids, perhaps configured as a personal stereo. The low-cost personal listening systems
now available are generally of very low quality (Dempsey, l994).
A number of very sophisticated programmable hearing
aids are currently on the market, with more, it seems, arriving every year. These are very impressive instruments from a technical
point of view, but they are also very expensive. Their comparative merits have not been objectively investigated. An independent
research program is required to evaluate the relative cost/benefit ratio of the different programmable hearing aids, comparing
them also to the performance of more conventional instruments for particular clients.
Realistic expectations are a
key to successful adjustment to hearing aids. Hard of hearing people who finally succumb to internal and external pressures
and try a hearing aid, and whose expectations are unrealistic, are sure to be disappointed. They tend to discard their hearing
aids, waste their money, discourage other people who may want to try hearing aids, and deprive themselves of the functional
improvement that is possible. But there is a fine line between discouraging unrealistically high expectations and minimizing
the potential benefit that hearing aids can provide.
Assistive Listening Devices
Hearing aids are the most common
assistive listening device, but they are not the only one. There are many situations where other types of listening devices
are useful and necessary, either with or without a hearing aid. At the present time, such devices are an "orphan" in most
dispensing practices. Telephone amplifiers, TV listening systems, wake-up alarms, signal and warning lights and direct input
microphones may be available for viewing in a glass cabinet, but rarely stressed during or subsequent to the hearing aid fitting.
These devices are relatively inexpensive, and there is not much profit in them for a dispenser. Therefore, it seems that relatively
few dispensers spend the time to evaluate the need for an assistive device, select the ones that may be best for a particular
person, show how it should be used, and then follow-up to make sure that the systems are being used, and used appropriately.
The need for, and advantages of, varying kinds of assistive devices and systems for many people with hearing losses
cannot be stressed too highly. Such devices can add immeasurably to the quality of one's life; how does one assess the ability
to engage in a relaxed phone conversation, to enjoy a TV program, to know that an important morning appointment will not be
missed, to know when the doorbell is ringing, or when the smoke alarm goes off? These, and other important contributions to
the quality of a hearing-impaired person's life, can be assured through the proper selection and use of assistive devices
and systems.
For many older people, it may be necessary to actually supervise the installation of an assistive device
in the person's house, or to demonstrate its use in an external assistive devices center. While this will rarely be feasible
for a private-practice audiologist, it is in this type of situation that chapters of Self-Help for Hard of Hearing People
(SHHH) can make a significant contribution. SHHH members have the motivation, knowledge, and opportunity to introduce hard
of hearing people to the potential advantages of assistive devices and systems. But they cannot help if such people do not
know SHHH exists. At the conclusion of every hearing and and assistive devices evaluation, health-care professionals should
ensure that they provide this information.
SUMMARY
Hearing aids are the most effective therapeutic measure we
can take to reduce the handicap normally imposed by a hearing loss. Coupled to other types of hearing assistance technologies,
they offer hearing-impaired people an opportunity to more fully participate in the full spectrum of activities societies have
to offer. Without, however, a sensitive and empathetic appreciation of the effects of a hearing loss on the part of society
in general, and without personal self-acceptance by a hearing-impaired person specifically, it will not be possible to realize
their potential benefits.
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Acknowledgement:
This paper was supported in part by Grant #RH133E30015 from the
U.S. Department of Education, National Institute of Rehabilitation Research to the Lexington Center.
By Mark Ross, Ph.D.,
FAAA, Professor Emeritus at the University of Connecticut
to e-mail: markross@uconn.cted.net
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