Glossary of Terms

Audiometer: Machine used for testing hearing.

Basal end of the cochlea: Toward the base, or bottom of the cochlea, the end nearest the round window, where high frequency sounds are processed.

Base level: A MAP parameter that sets the level on the digital amplitude scale below which no stimulation is sent to the recipient. The digital amplitude scale is from 1 to 150. The Loudness Growth Function starts at Base Level.

BTE: Abbreviation of Behind The Ear used in reference to the ESPrit, Esprit 22 and ESPrit 3G Speech Processors that rest behind the ear of the wearer.

Cochlea: The organ of the inner ear that converts mechanical vibrations into electrical impulses.

Cochlear: Abbreviation of Cochlear Limited the Cochlear Group or Adjective meaning of Cochlear Limited, e.g. a Cochlear employee.

Cochlear: Adjective meaning of the cochlea, e.g. extra-cochlear means outside the cochlea.

Cochlear Implant: An implanted electronic prosthesis which provides a hearing percept to the recipient via functional electrical stimulation of the auditory nerve in response to sounds detected by a microphone and speech processor worn outside the body.

Cochlear Implant Recipient: A person who has been implanted with a cochlear implant.

Coding strategy: An algorithm used in the speech processor to convert sound information from the microphone into a digital signal, which is sent to the cochlear implant.

Comfort Level: C-Level. The maximum Stimulus or Current Level, which does not produce an uncomfortable loudness percept for the recipient.

Conductive hearing loss: Mechanical hearing loss, which prevents sound vibrations being transferred to the cochlea.

Configuring a MAP: Manipulation of a recipient’s psychophysical data into a form that can be used for programming the speech processor.

dB: Decibel, a unit of relative measure that expresses the ratio of two levels (voltage, sound pressure etc.) on a logarithmic scale.

Dynamic Range: The difference between the comfort and threshold for one channel. It is given by the equation: Dynamic Range = Comfort Level - Threshold Level

ESPrit™ 22 Speech Processor: Cochlear’s behind the ear Speech Processor for the Nucleus CI22M implants and its variants.
ESPrit™ Speech Processor: Cochlear’s behind the ear Speech Processor for the Nucleus 24 implants and their variants.

FM: Abbreviation of Frequency Modulated radio signal.

FM cable: Cable used to connect a radio frequency (FM) microphone system to a speech processor.

Frequency Band: The name for pass band for the frequency filters often found in the audio conditioning stage of the SP.

Loudness: Perception of loudness as perceived by the recipient.

Magnetic Resonance Imaging (MRI): A medical diagnostic tool used to scan various parts of the body without the use of X-rays. Requires the use of an intense magnetic field and is prone to interfere with and receive interference from other magnetic material within the range of the scan. This interference may cause harm to the recipient.

MAP: A set of tables containing the parameters for the processing of the audio signals into the digital signals, which control the receiver/stimulator. MAPs are generated by using the Psychophysical results obtained in a Programming Session to optimize the hearing of percept of the recipient. MAPs are downloaded into the Speech Processor.

Neural MAPping™: Concept term used to describe the outcome from measuring intra-cochlear evoked signals, such as with NRT. The information from these measurements may provide an objective basis for determining the place, rate and intensity for cochlear stimulation.

Neural Response Telemetry (NRT): Telemetry measuring the response of the auditory nerve to electrical stimulation via a cochlear implant.

Noise Suppression: Method of processing sounds so that background noise is reduced.

Nucleus®: Nucleus is a registered trademark of Cochlear Limited, and the brand name used for Cochlear’s systems of cochlear implants.

Nucleus® 22: The Nucleus 22 system features the WSP, MSP, and Spectra speech processors.

Nucleus® 24: The Nucleus 24 system features the CI24M, CI24RST & CI24RCS implants, the SPrint and ESPrit speech processors, the CPS and PPS programming systems, and WinDPS clinical software.

Ossified cochlea: A cochlea in which a disease process has induced bone growth in the cochlear canals.

Post-lingual: After acquisition of language, e.g. post-lingual deafness. See also: pre-lingual, peri-lingual.

Pre-lingual: Before acquisition of language, e.g. pre-lingual deafness See also: peri-lingual, post-lingual

Profoundly hearing impaired: Hearing loss to the extent that the recipient has no useful hearing because they cannot hear sounds up to 90dB
Programming: The process of a Clinician working with an implant recipient to generate MAPs for the use of the recipient in their speech processor.

Self-curling Electrode: An intra-cochlear electrode array that's curved when manufactured, artificially straightened while it is being implanted, then allowed to curl once it is inserted into the cochlea. It is the intent of curly electrodes to sit closer to the modiolus and thus closer to the auditory nerve. This may provide more precise stimulation of the nerve and hopefully, a better perception of hearing.

Sensitivity: Sound pressure level required to make a speech processor behave in a particular way, e.g. generate a T Level stimulus.

Sensorineural hearing loss: Hearing loss caused by loss of nerve function or a damaged cochlea.

Spectra Speech Processor: Speech Processor for the Nucleus 22 implant and its variants. The Spectra is based on the MSP Speech Processor. See also: Speech Processor and supports the SPEAK, MPEAK and formant based coding strategies.

Spectral Maxima: The frequency filters with the greatest energy.

Speech Processor: Cochlear manufactured device that decodes sound into a digital signal and transmits it through the coil to the implant. See also: ESPrit, ESPrit 22, MSP, Spectra and, SPrint Speech Processors.

SPrint™ Speech Processor: with four MAPs, automatic noise suppression and volume control - for the Nucleus 24 cochlear implants running the SPEAK, CIS or ACE coding strategies.

Stimulus Control Knob: Rotary switch attached to the PCI and used by the clinician or implant recipient to control the adjustment of T level and C level stimulation on one channel at a time.

Stimulus Level: When the amplitude parameters are expressed as Stimulus Level, both the Pulse Width and the current amplitude of the stimulus pulse are varied in tandem to obtain loudness measures.

Stimulus Pulse: A single charge-balanced biphasic current pulse.

Switch on: A “switch on” is the first time a recipient is fitted with their speech processor after the implant operation, and the speech processor is switched on or activated.

Telecoil Radio frequency (RF): receiver coil to allow hearing aids and speech processors to pick up audio frequencies broadcast around a transmitter loop in halls, theatres, churches and other places where amplification is used. Telecoils are also used with telephones.

Telemetry: Measurement of various electrical parameters via feedback from the implant or other electrical measuring device.
Threshold Level: T-Level. The lowest stimulation level at which the recipient both identifies sound sensation and can detect a train of pulses every time it is presented.

Transmitting coil: The external coil attached to the headset and used to transmit RF across the skin to the coil in the implant.