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Dr. Ross on Hearing Loss

Telecoils as Assistive Listening Devices

by Mark Ross, Ph.D.

Small induction coils have been used in hearing aids at least since l946 (Lybarger, l982). The one I personally used in the early l950s was encased in small cube situated on top of the body worn hearing aid. It was spring-loaded and had to be physically depressed against the earpiece when I used the phone. (Long telephone conversations were avoided since they invariably produced muscle cramps in the arm!)

From this inauspicious beginning, telecoils (as they were soon labeled) have become smaller and more efficient. During the era when only body and behind-the-ear (BTE) hearing aids were available, most aids included telecoils. Since then, as the size of hearing aids has diminished, there has consequently been less room in which to fit a telecoil. This, and the fact that direct acoustical coupling can be quite effective with the smaller hearing aids, is responsible for the decline in popularity of telecoils. Currently, in the U.S., no more than 30%-40 % of current hearing aids include telecoils.

This is unfortunate in several respects. First, there are still many people for whom telephone conversation can be improved with the use of inductive (compared to acoustical) coupling. Without a telecoil in the hearing aid it is not possible to make this comparison. Second, and the main theme of this paper, is that by restricting our consideration of telecoils to its telephone application, we are overlooking what can be an equally important function: to serve as an assistive listening device. This was dramatically experienced by Dr. David Myers, a Michigan social psychologist (and the person who motivated me to write this paper) on a recent trip to Scotland).

During this visit, he attended a religious service that was taking place within the high stone walls of the 800 year old Iona Abbey. Before the services began, while listening to the babble of the other 300 worshipers, he just knew his experiences were going to be what they ordinarily were in such situations - half-heard words and lots of stress and aggravation. But his wife noticed a sign indicating that an induction loop system (ILS) was available, and she suggested that he switch on the telecoils of his hearing aids. He did, and now he feels that his life has been transformed by the resulting auditory experience. Suddenly the surrounding babble fell away, to be replaced by the sound of music emanating from musicians across the Abbey. When the services began, the leader’s words came across clearly and distinctly. For the first time in many years, Dr. Myers could actually attend to the service rather than strain to understand the words. As he continued his travels through Great Britain, attending professional, social, and religious events, he found that induction loop systems were available in just about all of the large events that he attended. Later he learned that IL systems were present in large settings throughout Europe. Why, he has been wondering, is this same type of auditory access not available in our country? Well, why indeed?

We could argue, of course, that it is available. The Americans with Disabilities Act (ADA), and particularly the latest set of ADA accessibility guidelines (ADAAG) requires that an assistive listening system (ALS) be provided whenever “audible communication is integral to the use of the space.” Except for a few exceptions (such as houses of worship) this applies to all large-area listening venues attended by the public. The specific type of ALS is left up to the local facility and can be an FM, Infra-Red (IR) or Induction Loop (IL). In practice, however, just about the only type of ALS installed in large venues have been FM and IR systems.

So what’s the problem? The problem is that the current situation hasn’t worked very well. While FM and IR assistive listening systems are available, they have not provided widespread auditory access to people wearing hearing aids. For a number of reasons the broad scope of auditory access that Dr. Myers achieved in Europe does not occur here.

Why FM and IR systems have been underutilized

The first reason is sheer inertia and lack of professional and consumer pressure. Large public facilities (such as auditoriums, theaters, movie houses, etc.) do not respond in a proactive manner. The fact that the ADA requires installation of an ALS does not cut much ice with most such facilities. Without continued pressure by those directly concerned, there is not much chance that managers of these facilities would spend the necessary money to obtain an ALS. Moreover, their resistance is likely to increase when they are informed that the care and maintenance of the ALS receivers are an ongoing responsibility for their facility.

It would be easier to convince them to install an ALS if receivers were not involved. Care of receivers necessitates that a staff member be assigned to oversee this function, with all the attendant responsibilities. This can be a burden, requiring, as it does, an increased workload, re-assignment of existing personnel, and frequent retraining of new employees. If receivers were not involved, facility managers could simply hook the ALS into the existing sound system and forget about it. The ALS would then be operative each time the PA system was activated.

Then there are the many facilities that do comply with the law and provide an ALS with appropriate FM and IR receivers. Many managers complain, however, that after spending the money and in spite of their good intentions, patrons very rarely ask for a receiver. Eventually, the receivers are relegated to a closet somewhere. Often, the newer employees are not even aware of the existence of the ALS. When a receiver is requested and one is located (likely at the dusty bottom of that closet), patrons often complain that it doesn’t work properly for one reason or another. Well of course it doesn’t; it may have been months since it was last taken out of the closet and used.

I myself have had experiences along this line. I helped several local synagogues acquire and install ALS systems, one of which was an FM system and the other an IR system. In both places, the ALS was hooked into the existing PA system; whenever, therefore, the PA system was turned on the FM or IR system would be transmitting. At first, in both locations, somebody (either a congregant or a maintenance man) took responsibility for ensuring that the receivers were available at the door prior to each service. In both places, there were initially rave responses by the few people who used the system. That was three or four years ago. Now, in both places, the receivers are locked in a closet somewhere and haven’t been in use for the last several years. Whenever the PA systems are turned on (i.e. in every service), the assistive listening systems are still doing their thing. But, unfortunately, their signals are not being “heard” and benefit nobody. This happens all the time.

Even when FM or IR receivers are available and working properly, hard of hearing people are often reluctant to request them. Many people do not like to draw attention to themselves by wearing a visible device, one that signals a hearing loss (not a healthy attitude in my opinion but still a reality). For some, the dangling of an IR receiver from the ears is an uncomfortable prospect after a few hours of wear. Other people object to using earphones or ear buds. And many others have had such poor experiences with the ALS they’ve used in the past (e.g. batteries that go dead in the middle of a performance) that they are reluctant to subject themselves to the same annoyance again.

Then there are lots of people, particularly older ones, who need a bit of extra help and encouragement in their first attempts to use an assistive listening device. Anything new or unfamiliar tends to be resisted. These people would be much more willing to simply switch their hearing aids to the “T” position, rather than search for the location where the receivers are being checked out (and have to provide some sort of ID), learn how to manipulate an unfamiliar device (it may look simple, but not to a first-time user), and then have to return it after the event (and find oneself the last to leave the facility). For lots of people, this is just too much of a bother.

In short, we have not been overly successful in this country in ensuring large area auditory access for the majority of people with hearing loss. Granted, when IR and FM systems work, and care is taken to ensure functional receivers, the listening advantages are apparent and wonderful. Still, for the reasons indicated above, we need to try another approach. This is not a trivial problem. There are millions of people out there with hearing loss whose appreciation of cultural and religious events is being needlessly restricted. This applies to just about everyone with a hearing loss. They can all benefit from an increase in the speech-to-noise ratio, which is the basic principle behind any type of ALS.

The telecoil as an assistive listening device

Clearly, then, the root cause of inadequate auditory access in many listening venues is the necessity to provide listeners with functional IR or FM receivers. Installation problems with these types of listening systems can be worked through; receiver issues, however, are perennial. They will always have to be checked out and somebody must always be responsible for doing this; weak and dead batteries will always be a problem; people will always resist wearing a visible device; reluctance to try something “new” will always be a factor; and individually “tailored” signals will never be possible. The only type of ALS now available that does not require an external receiver is the telecoil, since it is, itself, a “receiver” of electromagnetic energy.

Hearing aids are very personal devices. When people who wear hearing aids attend a performance or lecture, their aids accompany them. If an IL system is installed in the facility, then all they have to do is switch their T-coils on. Presto, they’re on the air! No need to check out receivers and no worry about weak or dead batteries. Furthermore, since the input signal from the telecoil simply substitutes for a microphone signal, the output is still “tailored” to the specific individual. (This assumes that the telecoil has been programmed to produce the same response as the microphone input, something possible with the newest generation of hearing aids.)

As noted above, only about 30% to 40% of the hearing aids worn in this country include a telecoil. In Europe, however, some 85% to 90% of hearing aids, generally BTE and ITE aids, include telecoils. This high percentage is undoubtedly influenced by the fact that IL systems have been available in Europe for many years. More than twenty years ago I noted that almost all the churches in Denmark had installed loops (Ross, l982). And as Dr. Myers’ experience suggests, the availability of IL systems on the continent has increased over the years. In Europe, unlike here, telecoils have long had an important role to play as an assistive listening device in addition to their telephone function.

We should also note that telecoils can also help in other ways. Many people permanently loop a listening area near their TV set, thus making TV sound access simple and convenient. No other receiver is required. Hearing aid users can adjust the volume to their satisfaction without bombarding the normally hearing listeners in the same room as them. Actually, of all the potentially useful applications of a telecoil, this one may be the most useful for the most people. But there are other applications as well.

Counter loops are now available that permit a hearing aid user to understand the clerk at such noisy places as airports and hotel counters (but good microphone usage is still a prerequisite). If more hearing aids contained telecoils, there would be an incentive for more facilities to provide these loops. Many other hearing aid users have found a neckloop to be an important accessory device. For example, I use a neckloop and as a two-ear connection with my telephone and answering machine (both of which have an audio output connection). Finally, there is a new highly directional array microphone now being marketed, termed the “Link-it,” which requires inductive coupling to a person’s hearing aids. So telecoils already have current and potential applications that transcend their traditional telephone function.

Implementing effective IL listening

There are going to be times when a hearing aid user would like to hear both the signal emanating from the loop and a companion’s occasional comments. When only telecoil reception is possible, such a person would have to switch the aid from the “T” to the “M” position. Not a big problem, but at times it can be inconvenient. There is an easy solution to this situation, something that first arose many years ago when IL systems were being used in educational settings with hearing-impaired children. We wanted the children to hear the teacher and each other directly, as well as being able to monitor their own speech output. Hearing aid manufacturers then provided another switch position, the “M/T,” in which both the microphone and telecoils were activated. While not a crucial consideration for adults, it would be desirable if hearing aids provided this choice in addition to microphone and telecoil options.

The specific physical orientation of the telecoil in the hearing aid has been a recurring concern (Preves, 1994). Inductive coupling is affected by the relationship between the magnetic field and the position of the coil. For optimal reception of a telephone signal, a horizontal positioning of the coil is recommended. To optimally detect a signal from a loop (floor or neck) the telecoil should be situated in the vertical position. Often recommended is a compromise position in which the telecoil is angled so that adequate (though not optimal) inductive coupling can be achieved with both telephones and loops. However, since it is much easier for people to manipulate a telephone for optimal coupling than to angle their own heads relative to a loop (!), I would suggest the vertical position as the normative one. Still, there is need for some creative engineering on the topic of telecoils, an area of research that does not seem to have interested the hearing aid industry very much.

Of course, initially, there would be legitimate objections if a facility only provided an IL system to its patrons. What happens to people who do not now have a telecoil in their hearing aids? Are they going to have to wait until they acquire new hearing aids before they can “tune” in to the system? As it happens, there are several commercially available IL receivers that can be employed to pick up the signal emanating from the loop. The use of these receivers does preclude the main advantage of the use an IL system, i.e., the convenience of using one’s personal hearing aid as a receiver. However, the IL receiver should be viewed primarily as a transitional and occasionally needed device. As more facilities are looped, and as more hearing aids contain telecoils, the number of these IL receivers could be reduced. At worst, having to check out a few IL receivers would be no different than the current situation. At the same time, the facilities could phase out the number of IR or FM receivers now required by ADA accessibility guidelines (4% of total number of seats, including 25% neckloops).

Installation of a large area IL system is likely to require more effort than the installation of either an FM or IR system. It takes skill to properly install any large area listening system, but the installation of a floor loop seems to be the most challenging. Signal spill over is a concern, particularly when adjacent areas are to be looped and used simultaneously. This may occur in convention centers, multiplex theaters, schools, and similar locations. One way this has been accomplished is by looping just a portion of an auditorium, sufficient for 65% to 70% of the seats, and clearly labeling the looped area. This would preclude significant spill over between adjacent sites and still give hearing aid users an adequate choice of seats. Incidentally, an excellent site for a IL system, where spill over would not be a concern is a house of worship, precisely that location not covered by the ADA.

We should recall that this is a technology that has been in use for many years, predating FM and IR systems by many decades. Possible problems have long been identified and mainly resolved. Yes, of course, in addition to spill over there are concerns about ambient electromagnetic interference (EMI) from such sources as defective lighting, power transformers, light dimmers, computer monitors, etc. Yet, by one estimate (Lederman, 2002) 9 out of 10 sites are sufficiently free of EMI to permit a satisfactory loop response.

There is always going to be a need for the unique characteristics of FM and IR systems. There are many times when an IR system would be the most appropriate (e.g. when privacy is a major concern) and other times when an FM system would be the system of choice (e.g. large outdoor stadiums, frequent changes of listening venues, etc.). What we should keep in mind is that all potential venues offer a unique challenge, and that there is no substitute for the advice offered by knowledgeable venders, installers, and hearing care professionals. The hearing care professional should not be a bystander in this effort to extend to use of IL systems in our society.

Right now, we seem to be in a “chicken and egg” situation: Most hearing aids do not include telecoils because they are perceived to be of benefit only with telephones, whereas there are relatively few IL systems out there because most aids do not include telecoils. I don’t think we can focus only on the “chicken” or only on the “egg.” Instead, I would suggest a combined approach, but one which emphasizes the role of hearing aid dispensers. They are in a position to strongly recommend the inclusion of telecoils in all of the hearing aids they dispense. At the same time, consumers and other interest groups can lobby strenuously for more IL installations. Unfortunately, a recent survey showed that less than 50% of all hearing aid dispensers even mentioned the possibility of a telecoil to their clients (Stika and Ross, 2002). Dispensers cannot, of course, require that their clients include a telecoil in their hearing aids, but people can be given enough information so that they can make an informed choice. Many people would be more than willing to accept the need for a slightly larger hearing aid if the potential benefits of a telephone coil were explained to them.

Our society is full of examples of how changes in terminology are intended to modify our views about people or topics. To stress the fact that telecoils have a role to play that far transcends their traditional one with telephones, it would be useful if we could re-label this little coil in order to stress its potentially wider application. Perhaps its time to change its name. Maybe if we now termed the “telecoil” a “listening coil” or “audio coil” we could be more effective in communicating its full scope as an ALD.

References

  • Lederman, N. (2002) Personal Communication.
  • Lybarger, S. (l982). Telephone Coupling. In G. A. Studebaker and F. H. Bess (Eds.), The Vanderbilt Hearing-Aid Report, Monographs in Contemporary Audiology (91-93), Upper Darby: PA.
  • Preves, D. A. (1994). A look at the telecoil – Its development and potential. SHHH Journal, 15(5), 7-10.
  • Ross, M. (1982). Communication Access. In G. A. Studebaker and F. H. Bess (Eds.). The Vanderbilt Hearing-Aid Report, Monographs in Contemporary Audiology (203-208), Upper Darby: PA.
  • Stika, C. J., Ross, M. and Ceuvas, C. (2002). Hearing aid services and satisfaction: The consumer viewpoint, Hearing Loss, 23(3), 25-31.
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