A
AUSLAN (Australian Sign Language)
A visual language that has its own structured word-order, grammar and vocabulary involving signs, body movements, facial expression, gesture, mime and finger spelling. It is different from English.
Acoustic feedback
Howl or whistle caused by the recirculation of acoustic output of an amplifying system. In a hearing device the sound emanating from the receiver may reach (or feedback into) the microphone and be reamplified until it builds up into a high-pitched whistle.
Acoustic nerve
Eighth cranial nerve, combining the nerves of hearing (cochlear) and balance (vestibular).
Acquired hearing loss
A type of hearing loss that is not present at birth. It occurs later.
Acute Otitis Media (AOM)
A type of ear infection characterised by an inflamed eardrum and usually accompanied by pain and fever. Discharge through a perforation of the tympanic membrane may occur. Some children may also suffer from a loss of appetite and may even vomit. Hearing in the affected ear declines temporarily.
Adaptive noise suppression
Some hearing devices have the ability to identify noise and suppress it. Adaptive noise suppression makes listening more comfortable when there is a lot of background noise that changes location, pitch and loudness.
Air conduction
When pure tones are presented through headphones, the measurement is called air conduction. The sounds go via the air, down the ear canal, through the middle ear, and to the very delicate cochlea in the inner ear.
Audiogram
An audiogram is a 'picture' of your hearing. It indicates how much your hearing varies from normal and, if there is a hearing loss, where the problem might be located.
Audiologist
Qualified audiologists are university graduates with postgraduate qualifications in audiology or equivalent training. A minimum of 12 months' supervised clinical practice in audiology is also required. Audiologists have broad responsibilities and expertise in all non-medical areas of hearing services including complex hearing assessment and rehabilitation of hearing impairment (which includes hearing aid prescription, fitting and management).
Audiometrist
Qualified audiometrists have completed a TAFE certificate course in hearing aid audiometry and received inhouse industry training. They have a minimum of three years' supervised experience in hearing assessment, hearing aid prescription and fitting, and management of hearing loss.
Auditory nerve
A nerve inside the head that carries signals to the brain and turns the signals into the sound that is heard.
Auditory-oral approach
A communication approach that emphasises the optimal use of residual hearing by maximising the use of either hearing aids or cochlear implants to listen and develop natural speech and language.
Auditory-verbal approach
A communication approach that uses listening to develop speech and language.
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B
Behavioral observation audiometry (BOA)
Testing that is carried out with infants younger than seven months of age using noisemakers. The child's behavioral response to these stimuli is observed and recorded.
Behavioural test
A type of hearing test for children that involves the observation of some change in a child's behaviour as a result of hearing a sound. The type of behavioural test used is dependent on the child's age and abilities.
Behind-the-ear (BTE) hearing aid
A type of hearing aid that is positioned behind the ear.
Bone conduction
The sensitivity of the cochlea can be tested by placing a small vibrator on the mastoid bone behind the ear. Sounds presented this way travel through the bones of the skull to the cochlea and hearing nerves, bypassing the middle ear. This type of testing is called bone conduction.
Brainstem evoked response audiometry (BERA)
BERA provides information on electrical activity generated in response to sound along the nerve pathway, also called the brainstem, to the brain. It may be carried out while a baby is in natural sleep. If this is not possible, testing must be carried out in hospital under sedation.
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C
Cerumen
The skin along the outer part of the canal has tiny hairs and produces a waxy substance called cerumen. This earwax has an important function. It discourages foreign objects from entering the ear, and prevents the skin of the canal drying out.
Cochlea
A tiny spiral shaped structure, about the size of a pea. It is nestled in the bone of the skull and filled with fluid. A thin membrane with around 15,000 tiny hair cells sits in this fluid. Each cell is tuned to a particular sound or frequency. The tiny hair cells connect to the cochlea nerve that sends messages along the auditory nerve to the brain.
Cochlear implant
A surgically implanted device that allows users to experience sounds as they occur by sending electrical signals to the nerve endings in the cochlea.
Community Service Obligation (CSO)
When the government specifically requires a government business enterprise to provide a service that the enterprise would not elect to do on a commercial basis.
Completely-in-the-canal hearing aid (CIC)
A type of hearing aid that is positioned completely in the ear canal. This type of hearing aid is suitable for people with mild hearing losses only.
Compression
The hearing device automatically adjusts the loudness of what you hear. When loud sounds occur the hearing device reproduces them at a comfortable level. In quiet conditions, this feature makes soft speech easier to hear.
Conductive hearing loss
Can be acquired or congenital and is caused by blockage or damage in the outer and/or middle ear. A conductive hearing loss can often be helped by medical or surgical treatment.
Congenital hearing loss
Present at birth, or soon after.
Cued speech
A visual supplement to speech that makes lip-reading more accurate.
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D
Decibels (dB)
A unit of measurement that indicates the loudness or intensity of sound, also used to measure hearing loss.
Digital hearing device
A hearing device that uses digital technology. A digital converter converts the sound into a series of numbers. The processor then performs arithmetic on these numbers to change the sounds before turning them back into an analog signal.
Directional microphone
An omni-directional hearing aid picks up sounds from all directions equally. Directional microphones enable hearing aids to amplify sounds coming from the side or behind the wearer less than they amplify sound coming from directly in front of them. This can make listening more comfortable in background noise as long as the listener is within a couple of metres of what they are listening to. The benefit of a directional microphone is greatest when the noise is coming from a single direction and there is little reverberation (echo).
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E
Ear canal
The ear canal varies in size and shape from person to person. It runs nearly horizontally toward the centre of the head for about 2.5cm (in adults) and ends at the eardrum.
Ear impression
A duplicate of the inside of the ear. A soft substance is placed inside the ear to form an impression that is used to produce a custom-fitting earmould for a behind-the-ear hearing aid.
Eardrum
Membrane of the middle ear that is cone-shaped and stretches across the ear canal. It is quite stiff but flexible and vibrates in response to sound waves
Electro-cochleography (ECochG or EcoG)
An EcoG picks up the tiny electrical signals generated in the cochlea in response to sound. It provides information about the functioning of the cochlea and the start of the nerve pathway to the brain. It is performed in hospital, under anesthetic.
Electro-physiological test
A type of hearing test that measures a physical response of a specific part of the auditory system. This type of test is especially valuable when behavioural testing is not possible or when a child's age or abilities make behavioural testing difficult.
Eustachian tube
A tube within the middle ear that connects the middle ear cavity to the back of the nose and throat. Its purpose is to adjust the air pressure in the middle ear to match the air pressure on the outside of the eardrum.
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F
FM soundfield amplification
The person speaking wears a small microphone which transmits (or sends) the voice to four speakers placed around the room via either radio frequency (FM) or infra red (IR) transmission. The speaker's voice can then be heard at the same volume level by the listener, no matter how far the listener is from the person speaking.
FM system
An FM system is made up of a microphone and transmitter worn by a teacher/parent and a receiver worn by a child/student. These systems are commonly used to transmit sound from one person to another over distance, overcoming the effects of noise, reverberation and distance.
Feedback management systems
Some hearing devices offer an electronic means of reducing annoying whistling (acoustic feedback). In some models this is achieved by altering the amplification provided by the device at certain frequencies. In other devices, this occurs by complex processing of the signal.
Finger spelling
An approach that is used in conjunction with other methods of communication. It includes 26 hand shapes representing the 26 letters of the alphabet. The two-handed alphabet is used in Australia.
Fluctuating conductive hearing loss
Conductive hearing loss associated with chronic Otitis Media (middle ear infection) is called 'fluctuating' as hearing levels do not remain stable over time.
Frequency
Frequency is the number of vibrations per second, expressed as Hertz (Hz). The sounds of speech are in the range of 250 Hz to 4000 Hz. The sensitivity of the ear to this range of frequencies is usually assessed in a hearing test.
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G
Glue ear
A type of Otitis Media (ear infection), common in children, where fluid exists in the middle ear in the absence of fever or inflammation of the eardrum. It is also referred to as Otitis Media with effusion (OME). The fluid is often quite thick and it may be in the ear temporarily or could persist for many months.
Grommets
Tubes inserted to aerate the middle ear to prevent glue ear recurring. The grommets cannot be felt by the patient and are usually pushed out by the eardrum after 6 to 12 months, leaving the eardrum intact.
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H
Hearing loss
Measured in decibels (dB) and usually described in terms of degree of impairment for hearing conversational speech.
Hearing services voucher
A letter issued by the Office of Hearing Services (OHS) to eligible adults who have completed an application form. The voucher holder is entitled to obtain a comprehensive range of hearing services free of charge.
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I
In-the-canal (ITC) hearing aid
A type of hearing aid positioned in the ear canal.
In-the-ear (ITE) hearing aid
A type of hearing aid that is positioned in the ear.
Induction loops or loops
In places where they are installed (often public places), loops eliminate background noise and improve the clarity of sound for hearing aid wearers with a telecoil (T Switch) in their hearing aid.
Infrared system
Transmits sound via invisible light to a receiver. The system can be connected to headphones or to an induction loop for use with or without a hearing aid.
Inner ear
The part of the ear where vibrations are changed into the signal that is carried to the brain, which is experienced as sound. It consists of a complicated series of channels and chambers, including the semicircular canals (organ of balance) and the cochlea (organ of hearing).
Intensity
Sound waves made by something vibrating gently have little intensity and the sound is soft. If an object vibrates strongly, sound waves have greater intensity and the sound is loud.
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M
Meniere's disease
A disease associated with symptoms such as dizziness, ringing in the ears, nausea, hearing loss, and fullness in the affected ear. The symptoms are linked to problems with bright lights, noise and movement and act as a series of attacks.
Middle ear
The part of the ear that begins at the eardrum, about 2.5cm inside the head. It includes three little bones - the hammer (malleus), the anvil (incus) and the stirrup (stapes) - that carry the sound vibrations to the area where hearing really begins.
Mild hearing loss, 21-45 dB
A degree of hearing impairment where individuals have some difficulty hearing soft speech and conversations, but manage to hear clear voices in quiet surroundings.
Mixed hearing loss
A type of hearing loss that combines the occurrence of both sensorineural (damage to the cochlea) and conductive (blockage or damage to the outer/middle ear) hearing losses.
Moderate hearing loss, 46-65 dB
A degree of hearing impairment where it is difficult for individuals to understand conversational speech, particularly in the presence of background noise. A good indication of a moderate hearing loss would be the need to significantly turn up the volume on the TV or radio.
Multiple channel hearing aids
Multiple channel devices divide the incoming sound into two or more frequency banks which can then be adjusted independently of each other. The main benefit of multi-channel devices is the flexibility they allow the clinician in adjusting the device to match more closely an individual's hearing loss and listening needs. Hearing devices with multiple channels enhance the advantages provided by compression - all channels control loudness independently.
Multiple listening programs
Listening environments change often and hearing devices with multiple programs allow the wearer to choose a signal processing strategy that best suits the situation. Some devices switch between settings automatically.
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O
OHS
The Office of Hearing Services is the Australian Government department responsible for the administration and regulation of the Australian Government's Hearing Services Program.
Ossicular chain
A chain of three middle ear bones (the hammer, the anvil and the stirrup). The hammer is connected to the eardrum membrane at one end and the stirrup rests against a membrane called the oval window that leads into the middle ear. The three bones vibrate together as the eardrum moves in response to sound. The stirrup moves in and out of the oval window like a piston.
Otitis Media with effusion (OME)
A type of ear infection also called glue ear. It occurs where fluid exists in the middle ear in the absence of fever or inflammation of the eardrum. The fluid is often quite thick and it may be in the ear temporarily or could persist for many months.
Oto-acoustic emission testing (OAE)
An OAE gives information about how hair cells in the cochlea are working. They respond to sound by producing a very soft sound of their own called an oto-acoustic emission.
Outer ear
The part of the ear that is made up of skin and cartilage and consists of the pinna (external flap of skin) and the ear canal.
Oval window
The oval-shaped membrane that leads into the middle ear.
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P
Pinna
The external flap of skin on the outer ear that helps you know the direction of sound.
Play audiometry
In play audiometry, children listen to sounds and are taught to make a response, such as put a marble in race or a peg in a hole, every time they hear a sound. Play audiometry is used to test the hearing of children from three years of age. It is also used to test a child's hearing when hearing devices are worn.
Post-lingual hearing loss
A type of hearing loss that is acquired after speech and language has developed.
Pre-lingual hearing loss
A type of hearing loss that occurs before a child has completely developed speech and language. It may be congenital (present at birth) or acquired.
Presbycusis
A condition associated with hearing loss and age. It is the inability to clearly understand speech and includes the social and psychological impact of hearing loss. Also known as early hearing loss, it represents what goes wrong with the hearing mechanism when ears age.
Profound hearing loss, 91 dB+
A degree of hearing impairment where normal conversational speech cannot be understood.
Pure tone audiometry
The most simple test of hearing ability. You listen to a range of beeps and whistles (called pure tones) and indicate when you can hear them.
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R
Recurrent Otitis Media (ROM)
The occurrence of three or more episodes of acute Otitis Media within a six-month period.
Round window
A membrane within the middle ear that is located just below the oval window. The round window allows the fluid to be displaced when it is pushed in the cochlea by the stirrup moving in and out.
Runny ear
When Otitis Media with effusion (OME) is present, the eardrum can burst releasing the fluid into the ear canal. Runny ear is when this fluid drains out of the ear.
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S
Selectivity
The ability to focus on sounds. A dozen separate sounds reach the ears at any given moment and under normal circumstances we have the ability to focus on any one of them. A hearing impairment can cause a loss of selectivity.
Sensorineural hearing loss
Can be acquired or congenital and is caused by damage to, or malfunction of, the cochlea (sensory part) or the hearing nerve (neural part).
Severe hearing loss, 66-90 dB
A degree of hearing impairment where normal conversational speech cannot be understood.
Signed English
A communication approach using the English language on the hands, word for word. It is expressed by using a combination of signs and finger spelling.
Soundfield amplification
The person speaking wears a small microphone which transmits (or sends) the voice to four speakers places around the room via either radio frequency (FM) or infra red (IR) transmission. The speaker's voice can then be heard at the same volume level by the listener, no matter how far the listener is from the person speaking.
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T
TTY (teletypewriters)
Text-based device enabling people with a severe or profound hearing loss to communicate via the telephone line.
Telecoil (formerly called a T-Switch)
A device in some hearing aids that allows magnetic coupling between a hearing device and another electronic communication device. If you have a telecoil there are many different assistive listening devices that give extra help in difficult listening conditions, such as on the telephone, at church and in the cinema.
Tinnitus
The term for noises which are heard in the ears or in the head - buzzing, ringing, whistling, hissing, pulsing and other sounds which do not come from an external source.
Top-up hearing device
A category of hearing device that can be obtained under the Office of Hearing Services (OHS) voucher scheme for an additional cost.
Total communication
A communication approach that uses any combination of signs, finger spelling, listening with amplification, cued speech, lip-reading, facial expression, body language, reading and writing to express meaning.
Tympanometry
A test of how well the middle ear system is functioning and how well the eardrum can move. A small rubber tip is placed in the ear and a little air is pumped into the outer ear canal. If there is a problem in the middle ear, it may show up on this test. The results of tympanometry can indicate the location of the blockage that is causing the hearing loss and whether medical treatment may help.
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UVW
USB
Universal Serial Bus
Visual reinforcement orientation audiometry (VROA)
Used to test the hearing of children between seven months and three years of age. By altering the frequency and intensity of sounds, it is possible to find out about a child's ability to hear sounds across a range of frequencies.
Voucher
Eligible adults need to apply to the Office of Hearing Services for a Hearing Services Voucher before they can receive hearing services from Australian Hearing or another provider of their choice. A doctor must fill in part of the form.
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