There is an abundance of jargon surrounding hearing loss. Trips to the audiologist can be overwhelming because of the language used in the appointments. Parents are expected to learn lots of new vocabulary in a short amount of time, which is not an easy task. Below is a collection of commonly used terms and phrases related to audiology, hearing loss, and cochlear implants. The explanations are written to help you better understand the terms you hear at audiology appointments, the phrases used to explain your child's hearing loss, and the terminology on the Comparison Chart. If there is a term you would like to see, or one you think other parents might want help understanding, please leave a suggestion on the Contact page.

 

 

• active length — The active length refers to part of the electrode array. Specifically, the active length is the distance between the first and the last electrodes in the array. The location of the active electrodes inside the cochlea determine the range of stimulation within the cochlea.

 

• age of amplification – The age at which your child is given a device which provides amplification (e.g., a hearing aid) is his/her age of amplification.

 

• age of identification – The age at which your child’s hearing loss is diagnosed is his/her age of identification.

 

• audiogram – An audiogram is a visual representation of your child’s hearing loss. The symbols on the audiogram represent the softest level your child can hear in each ear, measured in decibels (dB).

 

• aided audiogram – An audiogram that represents the softest level your child can hear while wearing his/her device(s).

 

• auditory nerve/cranial nerve VIII – The auditory nerve carries auditory information from the cochlea to the brain. When the auditory nerve function is atypical, the information doesn’t get to the brain and the sound is not heard clearly (or at all).

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• bimodal - A child who utilizes a cochlear implant on one ear and a hearing aid on the other ear is considered bimodal. This means the child is using two different modes of technology to access sound.

 

• cable – The cable is part of the external portion of the cochlear implant. One cable connects the speech processor to the coil. Another cable may connect the processor to the battery compartment (if your child is wearing his/her device in this configuration).

 

• channel – Each channel in a cochlear implant processes incoming information within a specific frequency range, then delivers the information to the appropriate electrode contact(s) for stimulation. Sometimes there are the same number of channels and electrodes in a device, and sometimes channels encompass multiple electrodes along the array.

 

• cochlea (plural: cochleae) – The cochlea is part of the inner ear. In a person with typical hearing, the cochlea is snail-shaped, filled with fluid, and contains tiny hair cells topped with tiny hair-like structures called cilia. These hair cells move with the fluid of the cochlea as a response to sound waves. This movement creates electrical signals that are sent to the brain via the auditory nerve. If an individual has missing or damaged hair cells, the cochlea is not able to create this signal, and it does not reach the brain (common in sensorineural hearing loss).

 

• cochlear implant – A device utilized by individuals with sensorineural hearing loss, who do not receive adequate benefit from hearing aids. A cochlear implant has two main parts, one internal and one external. The external part of the device includes a speech processor, a microphone, a battery or battery rack, a cable, and a coil. The microphone collects sound, which the external processor then converts into digital information. This information is sent up the cable to the coil which transmits the information across the skin to the internal part of the device. The internal part of the device is comprised of a receiver/simulator and an electrode array. The receiver/stimulator converts the digital information into electrical signals and sends them to the electrode array which is situated inside the cochlea. The electrical signals stimulate the auditory nerve and the information travels up the auditory pathway to the brain, where the sound is perceived.

 

• conductive hearing loss – Conductive hearing loss affects the outer and/or middle ear. This type of loss is a result of a physical blockage or damage to the middle ear system, that prevents sound from being conducted (or transferred) into the inner ear to be heard. Conductive losses can be caused by things such as fluid (infection), a perforation (tear) in the tympanic membrane, ossification (bony growth/hardening) between the middle ear bones, or a small tumor in the ear canal. Individuals with conductive losses are not eligible for cochlear implants.

 

• coil – Often referred to as the head piece, the coil is part of the external portion of the cochlear implant. The coil contains a magnet that holds the device on the user’s head. Sometimes, it also includes a microphone.

 

• degree of loss – Hearing loss can be classified as slight, mild, moderate, moderately-severe, severe, or profound. Each degree has a minimum and maximum decibel level. Not every hearing loss falls perfectly into one degree, so it is not uncommon if your child has a loss that "slopes," "falls," or "rises" from one degree to another or among multiple degrees of loss. With each increasing degree of hearing loss comes new challenges, such as environmental and speech sounds that cannot be heard. Generally speaking, the greater the degree of loss, the less that is heard.

 

• electrode array  – The electrode array is part of the internal portion of the cochlear implant and contains the electrodes. The electrode array is inserted into the patient’s cochlea during surgery/implantation. Electrode arrays come in various lengths and shapes, and one may be better than another for your child depending on the anatomy of his/her cochlea (this can be determined by the surgeon).

 

• electrodes – Electrodes create points of contact within the cochlea. The electrodes directly stimulate the auditory nerve, bypassing the damage in the cochlea due to sensorineural hearing loss.

 

• FM/DM – Your child’s audiologist and/or teacher may recommend the use of an FM or DM system. This is a system that may help your child to hear better and/or provide better access to a speaker’s voice when listening in a noisy setting or when listening from a distance. This system may use a frequency modulated (FM) or a digitally modulated (DM) signal to send information from the microphone worn by the speaker to the receiver(s) worn by the child. A receiver might be integrated into your child’s device(s), it may be attached to the device(s), or it may be worn as a neckloop.

 

• impact resistance – Impact resistance is the level of impact/force the implant can withstand (e.g., a child falling, getting hit in the head, etc.) without being damaged.

 

• implant –  The implant is the internal portion of the cochlear implant, which is surgically placed under the skin behind the user’s ear(s). The internal portion of the device is comprised of a receiver/simulator and an electrode array. The receiver/stimulator converts the digital information it receives from the external portion of the device into electrical signals and sends them to the electrode array which is situated inside the cochlea. The electrical signals stimulate the auditory nerve and the information travels to the brain, where sound is perceived. The implant also has a magnet in it, which attracts the magnet in the coil of the external portion, keeping the device on the user’s head.

 

• implant elevation/elevation height – A slight bump may be visible on your child's head where the implant is located under the skin. Some implants are thinner than others, so the manufacturers create an approximate “bump height” that can be expected after implantation. Sometimes surgeons create a recess in the bone to reduce the implant elevation.

 

• input dynamic range (IDR, Advanced Bionics & MED-EL)/instantaneous input dynamic range (IIDR, Cochlear) – Input dynamic range (IDR) or instantaneous input dynamic range (IIDR) is the amount of sound, in decibels (dB), from the softest to the loudest which is delivered to the user

 

• maximum stimulation rate – The maximum stimulation rate is the rate of information transfer from the electrodes to the auditory nerve (how quickly information is relayed). These rates are measured in pulses per second (PPS), which represents how many times per second information is sent from the electrodes to the auditory nerve.

 

• middle ear bones (ossicles) – The middle ear bones include the malleus, incus, and stapes. These three bones are housed in the middle ear space. In a typically functioning ear, these bones conduct (transfer) sound vibrations from the tympanic membrane to the cochlea. Some conductive hearing losses are caused by the inability of these bones to transfer sound, due to ossification (hardening), discontinuity (separation of the bones), or absence of one or more bone).

 

• mixed hearing loss – Mixed hearing loss is the combination of conductive hearing loss and sensorineural hearing loss in the same ear.

 

• omnidirectional/directional – Terms used to describe the microphones found on cochlear implants (and hearing aids). Omnidirectional means that the microphone picks up sounds from all directions. Directional means the microphone picks up sounds from a specific direction (such as in front of the user or behind the user) while reducing sounds from other directions.

 

• program – The speech processor of a cochlear implant is programmed to accommodate the user’s individual needs. Processors can hold multiple programs, which can be set for different environments (e.g., a program for listening in a noisy setting and a program for listening in a quiet setting). The user can switch from program to program via the remote or a button on the processor.

 

• recess depth – A small recess (carved out space) may be made in the bone during implantation so that the implant rests as flush as possible with your child's skull. The depth of these recesses is prescribed by the manufacturers depending on the size of the implant, and can be adjusted by the surgeon depending on the child’s anatomy.

 

• reliability – Reliability information is research from each manufacturer about the cumulative survival rate (CSR) of their respective implants.

 

• sensorineural hearing loss – Sensorineural hearing loss affects the inner ear and/or the parts beyond (like the auditory nerve). This type of loss is a result of damage to the cochlea, its hair cells, or the transmission of messages along the auditory pathway (the path sound takes from the ear to the brain). This prevents sound from being detected by the ear and/or interpreted by the brain.

 

• sound processing strategy – The sound processing strategy is how the device processes the sounds it picks up. One strategy might be more appropriate for your child than another based on a variety of factors (this can be determined by the audiologist).

 

• speech processor – The speech processor is the main part of the external portion of the cochlear implant (which also includes a microphone, a battery or battery rack, a cable, and a coil.). The microphone on the speech processor (or sometimes on the coil) collects sound, which the processor then converts into digital information. This information is sent up the cable to the coil which transmits the information across the skin to the internal portion of the device.

 

• telecoil – A telecoil is a coil of wire around a core within the device that allows the user to hear what is being said through a phone and/or when using an FM/DM system using an electromagnetic field. Some telecoils are integrated into the device, and some are only accessible through an attachable component or a neckloop.

 

• tympanic membrane – The tympanic membrane is more commonly known as the eardrum. This is the thin, semi-transparent membrane that stretches across the ear canal (separating the outer ear from the middle ear). Damage to the tympanic membrane can cause conductive hearing loss.

 

• type of loss – Hearing loss can be classified as conductive, sensorineural, or mixed.