Hearing impairment, or deafness, is when your hearing is affected by a condition or injury. Some people are born with a hearing loss while others may develop it as they get older.
Most commonly, hearing loss happens with age or is caused by loud noises.
Action on Hearing Loss (formerly the Royal National Institute for the Deaf) estimates that there are more than 10 million people in the UK with some form of hearing loss.
How hearing works
Sound waves enter your ear and cause your eardrum to vibrate. These vibrations are passed to the three small bones (ossicles) inside your middle ear.
The ossicles amplify the vibrations and pass them on to your inner ear where tiny hair cells inside the cochlea move in response to the vibrations and send a signal through the auditory nerve to the brain.
Types of hearing loss
There are three main types of hearing loss:
- conductive hearing loss – where sounds are unable to pass from your outer ear to your inner ear, often as the result of a blockage such as earwax, glue ear or a build-up of fluid due to an ear infection, a perforated ear drum or a disorder of the hearing bones
- sensorineural hearing loss – the sensitive hair cells either inside the cochlea or the auditory nerve are damaged, either naturally through ageing, or as a result of injury
- mixed hearing loss – it is possible to get both types of hearing loss at the same time
Levels of hearing loss
The level of hearing loss can be defined as mild, moderate, severe or profound. The level of hearing loss in an individual is determined by performing a hearing test to discover the quietest sound which that person can hear.
Some ear problems may not necessarily cause hearing loss, such as tinnitus, which is the sensation of a ringing or buzzing sound in the ear.
How can I check if I have a hearing problem?
If you think that you or your child may have hearing problems, see your GP. They will check your ear for any problems, such as earwax or a perforated eardrum (a hole or tear in the eardrum).
Your GP may refer you to an audiologist (hearing specialist) or an ENT surgeon for further tests, including tuning fork tests and Pure Tone Audiometry.
Hearing tests are routinely carried out on newborn babies within the first few weeks to try and identify any hearing problems. This is known as the Newborn Hearing Screening Programme (NHSP).
You might also wish to visit the Action for Hearing Loss website for an online hearing test.
Treating hearing loss
The way hearing impairment is treated depends on the type of hearing loss and how severe it is.
In cases where there is sensorineural damage, there are several options that may help to improve a person’s ability to hear and communicate. These include:
- Digital hearing aids, available through the NHS
- Middle ear implants – surgically implanted devices suitable for some people who are unable to use hearing aids
- Cochlear implants – small hearing devices that are surgically implanted inside the ear for people who find that hearing aids are not powerful enough
- Sign language, such as British Sign Language (BSL)
For people with conductive hearing loss there is often the possibility of improving their hearing with an operation or a device such as a Bone Anchored Hearing Aid (BAHA). This will often be discussed with an ENT surgeon who will diagnose the cause and offer treatment.
You may also wish to find services for hearing impairment and deafness support.
Preventing hearing loss
It isn’t always possible to protect a person’s hearing if they have an underlying condition that causes hearing loss.
However, there are several things you can do to reduce the risk of hearing loss from loud, consistent noise. This includes not having music or the television on at a very loud volume at home and using ear-protection at loud music events or in noisy work environments.
See your GP if there are signs of an ear infection, such as a high temperature (fever), flu-like symptoms, severe earache or hearing loss.
What to expect from a hearing aid
Hearing aids are exactly what they sound like – aids to hearing. If you wear a hearing aid then you may know how difficult it can be to adjust to a hearing aid in some situations and how challenging the relationship can be with a hearing aid.
Michael Simmons, who is a retired journalist, said in his book Hearing Loss from stigma to strategy that “Hearing aids may fit in the palm of your hand but they are an extraordinary thing with which to form a balanced relationship.”
The aim of a hearing aid is to help you hear more clearly in conversation and many other situations and to reduce the isolation you can often feel when you can’t hear by becoming more involved in everyday situations.
Hearing aids do not make any claims to return hearing to normal and have to work with the remaining hearing of the hearing impaired individual. However this seems to be the perception of the general public – that hearing aids restore good hearing in the same way that glasses restore good sight: if they see you have got hearing aids they think you can hear.
As hearing aids can only work with the amount of residual hearing you have left, it can mean that even with the help of hearing aids, some people who wear hearing aids may still have difficulties hearing in some situations.
A number of factors impact on how well someone might get on with a hearing aid:
- The severity of their hearing loss
- How much the clarity of their hearing has been affected through your hearing loss (known as speech discrimination)
- How much they wear their hearing aid
- How well people communicate with them (for example conversation happens face to face)
- What levels of background noise surround the people having the conversation
- The acoustics of the room
Modern digital hearing aids are programmed to take into account the hearing needs of the individual. A prescription is created from the hearing test completed in the assessment appointment.
This programs the hearing aid with the optimum level of amplification for hearing in speech. The prescription gives a good starting point for amplification however some people may have slightly different preferences for amplification and so the audiologist is able to adjust the hearing aid from its prescription when required.
Different types of hearing aids
Analogue Hearing Aids Provide simple amplification of the sound picked up by the microphone and reproduced louder by the receiver (loud speaker) in the hearing aid. The amplification can be shaped slightly to take into account different hearing losses although there is not always much flexibility. Overall it makes all the sounds louder.
Digital Hearing Aids provide amplification that can be more accurately shaped to take into account the hearing loss. Digital amplification splits the sound picked up by the microphone into small sections which are amplified depending upon the pitch and loudness of the sound to match an individual prescription. They often include programs for different situations, for example some social situations or work environments. They can also be reprogrammed if the hearing changes.
NHS Hearing Aids Since 2003 all National Health Hospitals have been routinely fitting digital hearing aids. In many departments, only behind-the-ear (BTE) styles are available. Other styles such as in-the-ear (ITE) are however available through private purchase from a hearing aid dispenser. NHS hearing aids are provided on a long term loan basis and without any charge, which includes all repairs, servicing and batteries required.
Private Hearing Aid Dispensers A private hearing aid dispenser can provide a wider range of hearing aid styles and technologies, and they will evaluate your needs to help identify the style of hearing aid and level of technology which would be the most suitable. Depending upon the dispenser visited, prices range anywhere from £200 to £3500.
Styles of hearing aids
Behind The Ear Hearing Aids
These have a microphone part that fits behind the ear and an ear piece that fits inside the ear. Ear pieces can either be made of plastic moulded to the exact shape of your ear (known as an earmould) or a thin plastic tube with a dome fitted inside the ear, known as an open fitting.
The suitability of the different ear pieces may depend upon the degree of hearing loss of the individual:
- An open fitting ear piece on a behind the ear hearing aid
- An earmould on a behind the ear hearing aid
This is a Behind The Ear hearing aid with a custom made ear piece (known as a meatal plug). Some custom made ear pieces differ slightly in that they fill the whole of the ear and are made from clear plastic – typically NHS Behind The Ear hearing aids.
RIC (BTE) Hearing Aids
These look similar to behind-the-ear hearing aids with an open fitting ear piece. The receiver (speaker) is situated within and open fitting ear piece in the canal rather than within the hearing aid.
This hearing aid provides many similar benefits to BTE hearing aids with an open ear piece and can therefore be used with more severe hearing losses than the open ear piece alone.
Receiver in the canal hearing aid
In The Ear (ITE) Hearing Aids
These have the microphone (and all other parts of the hearing aid) contained within a moulded ear piece which sits inside the ear canal. They range in different sizes from a completely in the canal style to a full shell.
There is nothing sitting behind the ear and can be more discrete than behind the ear hearing aids.
In The Canal Hearing Aids
They are small enough to fit almost entirely in the ear canal.
Completely In The Canal Hearing Aids
They fit deeply inside the ear canal.
For someone who is unable to fit a conventional hearing aid into their ear, maybe because of poor dexterity, a communicator may be a good option.
This is a simple analogue amplifier that uses ear pieces like a doctor’s stethoscope in both ears. It is set up the same for both ears and is suitable for up to moderate/severe hearing losses.
Body Worn Hearing Aids
These are available in analogue or digital technology for one or both ears depending upon hearing loss. Some but not all can be set up separately for individual ears. Wires from a body worn unit are connected to moulded ear pieces.
The unit can be worn in a pocket, on the belt or clipped to clothing depending upon its design. This style is an option for people with poor dexterity and who require a high powered hearing aid.
Bone Conduction Body Worn Hearing Aids
Mostly available with analogue technology, a bone conduction hearing aid picks up sound with a microphone and then transmits the signal via vibrations from a bone conductor device worn on a headband. They are typically worn by people with a conductive hearing loss (and usually when one or both ears are discharging).
Behind The Ear Bone Conduction Hearing Aids
Works similarly to the body worn device but the microphone part of the aid is worn on the opposite end of the same headband that holds the bone conductor. No visible wires are required although the headband is still required.
Bone Anchored Hearing Aids (BAHA)
A Bone Anchored Hearing Aid (BAHA) transmits sound directly to the cochlea (organ of hearing) by way of vibrations passing through the bone of the skull. To wear a BAHA a small screw is fixed into the skull, after a minor operation and the BAHA clips onto this screw.
The ear canals and middle ears are bypassed, making this a suitable option for patients with conductive hearing loss who may also have abnormal ear canals and middle ears and possibly discharge in the ear preventing them from wearing conventional hearing aids.
BAHA has also been used more recently for patients with a complete hearing loss in only one ear to help them pick up sound from the direction of the ‘bad’ ear. More about BAHAS.
Soft-Band Bone Conduction Hearing Aids
A BAHA version that requires no surgical intervention can be worn within a soft-band headband allowing sound to be transmitted through the bone of the skull to the cochlea (organ of hearing). This is very useful for very young children or for people wanting to trial a BAHA before undergoing surgery.
CROS Hearing Aids
For patients with no hearing in one ear and normal hearing in the other ear, a CROS hearing aid can be very useful. Whilst it cannot return hearing to the ‘bad’ ear, a CROS hearing aid has a remote microphone on the ‘bad’ side which picks up sound and passes it to the ‘good’ ear to be interpreted.
The microphone and receiver may be connected to each other by either a wire around the back of the head/neck or a wireless system. EastEnders actor Larry Lamb talks about his CROS hearing aid. Read his story.CROS BICROS hearing aid
CROS Hearing Aids – unwired
Some CROS hearing aids are wireless.
Some CROS hearing aids have wires which connect the microphone (which looks like a hearing aid and sits on the ‘dead ear’) to the hearing aid (on the hearing ear).
CROS Hearing aid with wires – BICROS Hearing Aid
Similar to a CROS hearing aid but with amplification also provided to the ‘good’ ear which may have some degree of hearing loss.
Features on some hearing aids
Hearing aid programsMost digital hearing aids have the option of having additional programs added to the standard program which is set for most listening situations you encounter. By having extra programs the hearing aid can be more flexible in a specific situation, for example in background noise.
Directional microphones/noisy situationsTwo microphones work as a pair to help the hearing aid to focus on sound coming from in front of the listener and to reduce sound coming from behind the listener. This setting does not remove background noise completely and requires the listener to think about their own communication. They may need to think about where the speaker they are listening to is sat and adjust their own position to gain the most benefit from their hearing aids.
The loop system/telecoilInduction loop signThe loop system or telecoil is a special kind of microphone system designed for hearing aid users. It is commonly found in public buildings including banks, post offices, churches and theatres among many more. If a building has a loop system they will display a sign – see right.
To pick up sound from the loop system, the hearing aid wearer has to switch their hearing aid to a specific setting. If the hearing aid has a T (pure telecoil) setting, the listener will pick up only the loop system. If the hearing aid has an MT (half microphone and half telecoil) setting, the listener will pick up a combination of the loop system and the normal microphone setting.
Signs often tell the listener to switch to the ‘T’ setting – this refers back to the days of analogue hearing aids and some earlier digital hearing aids which had a specific loop system switch labelled ‘T’. Many more recent digital hearing aids have a button with multiple settings which is pressed a set number of times to access the loop or ‘T’ setting.
Remember to switch back to ‘normal listening’ setting after finishing using the loop system or you may not be able to hear clearly.
Music programBy developing music programmes, patients may be able to appreciate the quality of music more effectively when wearing hearing aids. There are various strategies that your Audiologist may apply to try to improve the quality of music within your hearing aid programming. These changes will alter how the hearing aid reacts – normally a hearing aid aims to optimise the perception of speech stimuli, settings which may not be optimal for listening to music. Some hearing aids already have this option available and your Audiologist may just need to select this option within the programming.
Telephone settingSome hearing aids have a specific setting (that like the music program above) which is optimised for listening to something other than a basic speech sound. Telephone signals do not cover the whole range of speech sounds and so the hearing aid may need to be adjusted to take this into account. Again there may already be a pre-available setting your Audiologist can select or they may be able to make adjustments to your aid to help with this. Some digital hearing aids have an automatic telephone setting that is switched on when a telephone is held next to the ear and switched off when the telephone is removed again.
There is no right or wrong with the telephone. Some people use telephones with their normal hearing aid setting, some use a telephone setting or the loop system with a special telephone. Others choose to use just an amplified telephone with or without their hearing aid. Regardless of the hearing aid and telephone method chosen, a listener is likely to find improved sound with the telephone when the receiver is held next to their hearing aid rather than their ear and ear mould.
Compatibility with other devices
With the constant improvements in digital technology and the more widespread use of Bluetooth and other wireless technologies, it was only time before this made its way into the world of hearing aids.
Several hearing aid manufacturers now produce devices that can be used with their hearing aids to allow wireless connection to various devices including mobile telephones, televisions and other digital electronic devices allowing the hearing aids to pick up sound input directly from these devices.
Some hearing aids (not currently available through the NHS) actually have bluetooth technology built into the hearing aid itself, allowing the same kind of connections, but without the need for a separate device.