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Please find a wealth of glossary terms below:


Acute otitis media
Acute otitis media, or glue ear, is a short-term ear infection that often comes on suddenly. Symptoms are a build-up of fluid in the middle ear, which can get infected.
Age Related Hearing Loss
Hearing loss that is caused by advancing years rather than by illness, medication, exposure to loud noise or trauma.  About 60% of those with hearing loss in the UK are over retirement age.
Analogue hearing aids
Analogue hearing aids have a microphone that picks up sound and converts the sound into small electrical signals. These electrical signals are then amplified (made louder) and fed into an earphone on the hearing aid so you can hear them. They have largely been replaced by digital hearing aids.
An audiogram is a chart that represents a person’s hearing ability, determined by a hearing test. Audiologists use audiograms to help judge whether a person has a hearing loss and what type of help they need.
An audiologist specialises in identifying and assessing hearing and balance problems. They recommend and provide appropriate support, products and treatments to help alleviate the effects of hearing loss.  Audiologists can work both privately and for the NHS.  Audiologists in the private sector who are members of BSHAA provide the additional assurance of the Society’s Customer Care Scheme
Auditory nerve
The auditory nerve (also known as the cochlear or acoustic nerve) carries (sound) signals from the cochlea to the brain.
Auditory processing disorder
A disorder that affects the processing of auditory information within the brain. Typically the patient has normal functions of the outer, middle and inner ear but are unable to process sounds in the same way that others do. therefore having difficulties recognising and interpreting sounds, especially speech.


Behind-the-ear (BTE) hearing aids
BTE aids have a mould that fits inside the ear, while the rest of the aid sits behind the ear. Some have twin microphones, to switch between all-round sound and a more directional setting that can provide focused directional sound in noisy places.
Bone conduction hearing aids
Bone conduction hearing aids deliver sound through the skull via vibrations.
Brain stem implants
Brain stem implants are inserted surgically and can improve hearing in patients with neural hearing loss, which can be caused by cancer of the auditory (hearing) nerve or an auditory nerve that failed to develop properly. Implants convert sound into electrical impulses that stimulate the brain directly, bypassing the auditory nerve. 
British Society for Hearing Aid Audiologists


A condition of the middle ear that generally starts with a hole in the ear drum; usually in the upper part of the drum. This can become infected and the ear drum sheds dead skin which mixes with other debris in the ear to form a mass – called a cholesteatoma. If left untreated this can grow causing damage and may lead to hearing loss, tinnitus and sometimes balance problems. Rarely, very severe cases can cause meningitis or brain infections.
Chronic otitis media
Chronic otitis media is a long lasting or recurring infection in the middle ear.  Symptoms are a build-up of fluid in the middle ear.
The cochlea is a fluid filled chamber in the inner ear which converts sound to electrical impulses in the auditory nerve.   Sound waves enter the cochlea from the middle ear causing the fluid to vibrate.  Tiny sensory hair cells to pick up this movement and trigger the signal in the nerve which passes the signal to the brain to be interpreted as sound.
Cochlear implant
A cochlear implant consists of a microphone and a transmitter outside the head, which send signals to a receiver under the skin which is connected to electrodes implanted in the cochlea. Sound causes tiny electric currents which stimulate the auditory nerve and in turn the impulses are passed to the brain to be interpreted as sound.
Completely-in-the-ear-canal (CIC) hearing aids. Also IIC (invisible)
CIC’s are even smaller than ITE aids, so are an excellent solution for people who need a less visible hearing aid. 
Hearing aids amplify weak sounds to a level that the user can hear. They also ensure that strong sounds are not amplified too much to avoid discomfort. Compression is the system that manages this, and enables a user to listen comfortably to quiet and loud sounds in quick succession without having to manually change settings.
Conductive deafness
Conductive deafness is when sound cannot pass freely through the outer or middle ear. This is usually caused by a blockage in the outer or middle ear from an infection or a build up of wax. If the cause is wax this can be removed by an audiologist.  BSHAA’s Find an Audiologist will help you identify an dispenser near you who offers wax removal.


Digital hearing aid
Digital hearing aids take signals from the microphone and convert this into a code. The code is manipulated by a tiny computer in the hearing aid, so enabling digital hearing aids to be set to an individual’s hearing needs.
Directional microphones
Some hearing aids have multiple microphones to help detect the direction of a sound source. This helps the hearing aid to focus more on sounds coming from the front of the person, rather than the side or behind. The microphones make it easier to follow conversations in noisy places.


Hair cell
Hair cells are sensory cells in the cochlea that convert sound vibrations into electrical signals that then travel along the auditory nerve to the brain. Loss of or damage to hair cells results in permanent hearing loss.
Hearing loss
We use the term ‘hearing loss’ in a general way to cover any impairment in hearing, from mild hearing loss (unable to hear sounds below 25dB) to profound deafness (unable to hear sounds below 95dB).
Hyperacusis is abnormal discomfort caused by sounds that are tolerable to listeners with ordinary hearing. Many people who experience hyperacusis will not have hearing loss, but it is commonly linked with other hearing problems such as tinnitus or Meniérès Disease.


In-the-ear (ITE) hearing aids
ITE aids are small enough to fit inside the ear, although not as small as CIC aids. Working parts are either in a small compartment clipped to the earmould or inside the moulded part itself. 


Loop system
Also known as an induction loop, a loop system is an assistive listening device that can be used with some hearing aids in places where it might be difficult to hear.  Loop systems are commonly available in public places such as banks, post offices and theatres.  Hearing aid users need to switch to the T or telecoil setting to use a loop system.


Meniérè’s disease
Meniérè’s disease is a rare condition that affects the inner ear. It can cause vertigo, tinnitus, hearing loss and a feeling of pressure or fullness in the ear. Symptoms usually appear without warning and often last for two to three hours.


Noise-induced hearing loss
Noise-induced hearing loss is when we are exposed to sounds that are too loud, or loud sounds that last a long time, sensitive structures in our ear (hair cells) can be damaged. This causes noise-induced hearing loss. Once damaged, our hair cells cannot grow back, so this hearing loss cannot be reversed.
Noise suppression
A system within hearing aids that works to reduce some kinds of background noise automatically so that listening is more comfortable.


Open ear fitting
Conventional ear moulds are not required for open ear fitting. Instead, the hearing aid sits behind the ear and a small tube carries the sound into the ear and is held in place by a small tip and/or sprung plastic projection. These small earpieces can give a more natural sound and do not feel as ‘full’ in the ear as conventional ear moulds.
Otitis media
An infection or inflammation of the middle ear, usually caused by a viral or bacterial infection.
A condition which results in the abnormal growth of bone in the middle ear. It can cause conductive hearing loss. The excess bone prevents the ossicles in the middle ear from moving freely. Hearing loss of this type causes sounds to become quieter rather becoming distorted.
Ototoxic drugs
Drugs that may be damaging to the ear or hearing are known as ototoxic. Some ototoxic drugs may make tinnitus and/or hearing temporarily worse and some can cause permanent damage.


Perforated eardrums
A hole or tear in the eardrum. It will usually heal by itself, but it can sometimes require surgery called myringoplasty, where a tissue graft is used to seal up the hole.
Most people find their hearing gets worse as they get older – this is called age-related hearing loss or presbycusis. If you have noise-induced hearing loss and you develop presbycusis too, the combination will mean that your hearing loss is worse than presbycusis alone.


Real ear measurement
Real ear measurement is a method used by an audiologist to make sure that hearing aids are set up the right way for an individual by measuring the sound levels in ear canals.
Receiver-in-the-ear (RITE) hearing aids
RITE, or loudspeaker-in-the-ear aids are smaller than BTE aids, because some part of the device sits inside the ear. They are not as small as ITE or CIC aids. Like open ear BTEs, they can be easier to put in than an ear mould. There are different RITE hearing aids for different levels of hearing loss.


A telecoil is a small coil of wire within a hearing aid that enables the hearing aid user to make use of a loop system.
Tinnitus is experienced as noise in the ears or heard. The sound produced by tinnitus is normally described as ringing, whistling or buzzing.
Tinnitus (Pulsatile)
Pulsatile tinnitus is normally described as rhythmic noise that beats in time with your pulse. This type of tinnitus usually has a specific cause, such as high blood pressure or glue ear.