Best Hearing Aids For Tinnitus
Along with artificial additions to the heart, keyhole surgery and laser treatment, the hearing-aid today represents a marvel of science and technology. The ear-trumpet of other centuries and the body-worn, cumbersome equipment provided in the early days of the National Health Service are now curious items in medical museums. The technology of miniaturised engineering has come to the rescue of millions of deaf people, enabling them to make the most of any hearing they still have.
Tinnitus, so close to, yet profoundly different from, deafness in many ways, has become something of an accidental beneficiary of the dramatic improvements made in the design and manufacture of aids in recent decades. A person with tinnitus and quite a lot of hearing loss can benefit from wearing something that can amplify speech and other sounds to enable him to hear better. He can also have a sound-generating masker incorporated in the aid to blot out or distract attention from the tinnitus sounds. Fortunately the aid can additionally be of help to anyone with tinnitus but without deafness.
To understand how anyone with good hearing can find any use in having an aid in one or each ear it is necessary to know how countless sufferers manage to go through life putting up with the racket in their heads. Although most find they wish to avoid noisy places, total silence can increase the tinnitus. Various levels of sound between these two extremes can bring relief. Depending on the personality, the degree of tinnitus and perhaps other medical conditions, acceptable volume and type of sound can reduce the personal perception of internal noise. Music and speech thus become so important; a sufferer will often say, for instance, that buying enough radios to have one in every room in the house can be the best of all investments.
Except for those people with hypersensitive hearing, most uninvited sounds throughout the day are acceptable. The neighbour's lawn-mower, the passing bus, the bark of a dog are, in moderation, only indications of the world around us in which most people are content to play a role. The tinnitus sufferer, with his sounds intricately bound up as much with the brain as with the ears, seems subconsciously to find consolation in the sound of the world beyond his personal affliction. He is silently rejoicing that sound, so unwelcome when uninvitedly squatting in his head, still takes many benign forms in the world. With or without such philosophy, ambient sounds certainly have the power to make the tinnitus recede and lose its potency. And this is where a hearing-aid helps.
The NHS does not openly dispense hearing-aids solely to help tinnitus when a patient has no hearing loss. Where the deafness is quite slight a person can, however, find himself wearing an aid almost wholly to the advantage of his tinnitus and scarcely, if at all, to correct the deafness of which he may not even be aware. The aid slightly exaggerates the everyday sounds around him and thereby cuts back the conscious awareness of the tinnitus.
It is a matter of personal adaptation and trial and error to discover at what volume setting to use the aid in order to block the tinnitus. In a busy, noisy street the sound of traffic and pedestrians can actually assist and the lowest setting can often be chosen. In a quieter place like a park, a higher setting enhances the natural aural ambience, so checking the ill-effects.
Another category of sufferers – those with some deafness but not willing to admit it, saying that it is simply tinnitus blocking out clear conversation – can be agreeably surprised at what an aid can do for them. They may still maintain, quite inaccurately, that the improved hearing is because the aid is reducing the tinnitus. There is probably no harm in their misconception. There is undoubted benefit to be enjoyed in their better hearing and the anti-tinnitus effect of wearing an aid.
Where there is more deafness in one ear than the other (with or without tinnitus) the conventional and proven wisdom is to wear the aid in the better ear, contrary to what a newly deafened person may think. When the aid is primarily used as an anti-tinnitus device, as described above, the choice is not so straightforward. Head sounds can be experienced as if they are in one or both ears, or in neither and in the head generally.
Unlike choosing the better ear in the case of deafness, it can be best to opt for the ear with the worse (or sole) sensation of tinnitus. If that one happens to be the deafer also, the use of two aids suggests itself, with different volume settings in each. If there is no noticeable deafness, but the tinnitus is somewhere in the middle of the head, it can be a matter of trying the aids separately in each ear and in both.
For some there is a simple test of the anti-tinnitus properties of aids essentially made to help the deaf. The wearer should spend a little time in a busy street with the volume adjusted fairly low. Still close to traffic, she should then quickly switch off the aid without first reducing the volume. The immediate result is not just reduced traffic noise but a brief but distinct increase in the tinnitus, as if it were keen to reassert its dominance once the enhancement of ambient sounds had ceased. After a second or two the tinnitus falls to its usual volume, but the person is left with proof that a hearing-aid can be a boon.
Assisting a partly-deaf person to hear is never just a case of speaking more loudly, though that helps. Good hearing involves the constant recognition, separation and perception of sounds of varying pitch, frequency and timbre, at great speed and largely without the conscious knowledge of the hearer. A piece of equipment that essentially amplifies sound is therefore of limited potential to either the deaf or the tinnitus-stricken, though better than nothing. The earlier aids and many in current use crudely act as amplifiers, and have not always matched up to the seemingly basic yet complex task of achieving a degree of aural normality.
But the future is becoming brighter. It is misleading to talk of artificial ears; were they ever to be in reach, the brain could not be relied on to relinquish its mysterious part in the creation of tinnitus. Yet in the not-too-distant future hearing-aids could be as refined and sophisticated as any spare parts now being implanted routinely to compensate for malfunctioning organs in the body. They could be made by bespoke engineering tailored to an individual rather than the current off-the-peg equipment which still constitutes most of what is on offer. This will add to the masking qualities of aids and, for dual tinnitus-deafness sufferers, lighten the burden of deafness and enable them to fight their tinnitus more confidently.
The real hope of better things to come lies largely in highly specialized research being undertaken at Cambridge University. A research team there is analyzing the commonest causes of deafness and is already reporting with some confidence how distorted and diminished sounds reaching the ear can be corrected.
Most people's hearing loss is caused by damage to the sensory cells in the inner ear, which process incoming sounds of all sorts from a whisper to a clap of thunder. Their great virtue is having a mechanism referred to as automatic gain control (AGC) or compression which boosts weak sounds. This is lost in a deaf person. The threshold for detecting sounds is higher but the level at which sounds are uncomfortable stays the same.
In these circumstances a conventional hearing-aid amplifies sounds equally so that when weak sounds are audible the louder sounds are uncomfortable. There is also a mechanism in normal ears which refines the selection of frequencies in complex sounds and enables speech to be understood, even when there is background noise. Hearing-aids are badly needed to incorporate signal processing and to compensate for any loss of the natural mechanism.
The Cambridge research team, which specialises in hearing aids, has made possible the development of a prototype aid with three separate types of AGC, all of which is of real relevance to people whose tinnitus interferes with their hearing:
- The first type adjusts the volume sensitively, so that the wearer can move from a quiet environment to a noisy one, without experiencing discomfort. The wearer does not have to adjust the controls.
- The second control acts very quickly to protect a person from sudden loud sounds like china breaking or a door being slammed. The intervention is brief enough to deal with the sudden noise but without changing the sounds – perhaps voices – that follow.
- The third, and most rapid, form of control is to enable a person to hear weaker speech sounds such as "p' or 'k'. It increases weak high frequency sounds, making speech more intelligible, especially in noisy situations.
Laboratory work is also proceeding to improve the degree to which amplification is matched to an individual's general needs at different frequencies. People who become deaf through age or loud noise have greater hearing loss at the high frequencies. It will be a great step forward when a standard hearing-aid reflects these different needs. New digital processing techniques will also one day make possible greater hearing clarity and isolation of a single voice in a crowded room. Some of the more expensive hearing-aids sold privately already have some AGC and some programmable aids have settings which adapt to different situations throughout the day. To find out more, you can check out Best Hearing Aids For Tinnitus.