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Glossary of Terms


Acoustics: pertaining to sound, the sense of hearing, or the science of sound.

Acoustic room treatment: the use of sound-absorbing materials (such as carpet and acoustical tile) to reduce ambient room noise and improve the signal-to-noise ratio, thus enhancing the usefulness of hearing aids, cochlear implants, and other types of amplification.

Acquired hearing loss: a hearing loss that is not present at birth; sometimes referred to as an "adventitious loss."

Air conduction (AC): sound from the air delivered through the ear canal, the eardrum, and middle ear to the inner ear.

Ambient noise: background noise that competes with the main speech signal.

American Sign Language (ASL): a visual-spatial language used in the United States and Canada. Linguistic information is conveyed by the movement of hands and non-manual signals received through the eyes and processed in the language areas of the brain. ASL has its own rules of grammar, phonology, morphology, semantics, syntax, and pragmatics.

Amplification: the use of hearing aids and other electronic devices to increase the loudness of sound.

Assistive listening devices (ALDs): all types of electronic hearing aids, including personal aids, FM systems, infrared systems, special input devices for telephone or television, amplified alarms and signals, etc.

Audiogram: the graph on which a person's thresholds (loudness level at which a person just perceives a sound) is plotted for different frequencies (pitches).

Auditory neuropathy spectrum disorder (ANSD): a variety of hearing loss in which the outer hair cells within the cochlea are present and functional, but sound information is not consistently transmitted to the brain by the auditory nerve, resulting in a dyssynchronous signal to the brain.

Auditory/oral: a communication methodology that encourages children to make use of the hearing they have (residual hearing) through the use of appropriate technology (e.g., hearing aids, cochlear implants, FM systems) and therapeutic intervention. In this approach, children are taught to listen and speak.

Auditory training: the process of training a person to use his or her amplified residual hearing for the recognition, identification, and interpretation of sound

Aural habilitation/rehabilitation: training designed to help an individual with elevated hearing levels to make productive use of amplified residual hearing that may or may not include training in speechreading/lip reading.

Bicultural: belonging to two cultures, such as Deaf culture and hearing culture.

Bilateral vs. unilateral: bilateral hearing loss means both ears are affected; unilateral hearing loss means only one ear is affected.

Bilingual: being fluent in two languages; for some deaf children, this includes the use of ASL and English. Bone conduction: sound received through the vibration of the bones of the skull.

C-Print: a speech-to-text system developed at the National Technical institute for the Deaf (NTID) at the Rochester Institute of Technology (RIT) as an access service option for some D/HH students in educational environments; printed text of spoken English is displayed in real time with a meaning-for-meaning representation of the spoken word.

Captionist: the person who provides real-time captioning for a student using either C-Print or CART (see below).

CART (communication access realtime translation): instantaneous verbatim (word-for-word) translation of the spoken word into English text using a stenotype machine, notebook computer, and real-time software with a display of the text on a laptop computer, monitor, or screen.

Central auditory processing disorder (CAPD): a condition typically associated with normal hearing levels that affects the ability to decode the sounds a person hears. CAPD appears to result from a dysfunction in part of the brain that process sound. It differs from ANSD (see above) in that the latter is a result of the auditory nerve delivering sound to the brain inconsistently.

Cochlear implant: an electronic device surgically implanted to stimulate nerve endings in the inner ear (cochlea) in order to receive and process sound signals to send to the brain via the auditory nerve.

Conductive hearing loss: difficulty for sound to be "conducted" to the nerves in the inner ear caused by a problem in the outer or middle ear. The amount of loss depends on the nature of the cause of the sound conduction issue.

Configuration of loss: the amount of hearing loss at each frequency (pitch) and the overall picture of hearing that is created on an audiogram (see above).

Congenital hearing loss: a hearing loss that is present at birth or that is associated with the birth process or that develops in the first few days of life.

Cued speech: a phone-based system that makes traditionally spoken languages accessible by using a small number of handshapes, known as cues (representing consonants), in different locations near the mouth (representing vowels), as a supplement to speechreading.

Deaf: a cultural, linguistic term that means that a person's communication mode is visually based (either sign language or written English); residual hearing (if any) may be a secondary and supplemental sensory avenue.

Deafblind: any combination of documented hearing and vision loss, ranging from mild to profound hearing loss and low vision to total blindness; students who are deafblind should be reported to the Ohio's Center for Deafblind Education (https://ohiodeafblind.org) for additional services.

Deaf community: the community of people whose primary mode of communication is ASL and who share a common identity, a common culture, and a common way of interacting with each other and the hearing community.

Decibel (dB): the unit of measurement for the loudness of sound; the higher the dB, the louder the sound.

Degree of hearing loss: the severity of hearing loss, typically divided into seven categories. The numerical values are based on the average of the hearing levels at three frequencies, 500 Hz, 1000 Hz, and 2000 Hz, in the better ear, without amplification. Some people use slightly smaller or slightly larger numbers for each of the following categories:

  • Normal range = -10 to 15 dB
  • Slight loss/minimal loss = 16 to 25 dB
  • Mild loss = 26 to 40 dB
  • Moderate loss = 41 to 55 dB
  • Moderate/severe loss = 56 to 70 dB
  • Severe loss = 71 to 90 dB
  • Profound loss = 91 dB or more (www.ASHA.org)

Ear mold: a custom-made acrylic, vinyl, or silicone piece that fits into the outer ear to send sound from a hearing aid into the ear.

Fingerspelling: manual representation of the alphabet by finger positions, in order to spell out words or longer strings of language.

Fluctuating vs. stable hearing loss: some types of hearing loss change; sometimes improving, sometimes worsening. Such a change commonly occurs in young children who have hearing loss as a result of otitis media or fluid in the middle ear (conductive). While hearing losses of a sensorineural nature can fluctuate as well, those that remain the same year after year are regarded as stable.

FM system: a wireless assistive listening device that consists of a transmitter (worn by the speaker) and a small receiver that couples to a hearing aid or cochlear implant or bone-anchored hearing aid (BAHA). The speaker's voice transmits directly to the receiver, reducing the effects of background noise and loss of intensity due to distance from speaker.

Frequency: the number of vibrations per second of a sound. Frequency, expressed in Hertz (Hz), determines the pitch of sound.

Gesture: movement of any part of the body to express or emphasize an idea, an emotion, or a function. Gestures are not part of a formal communication system.

Hard of hearing: an individual with partial ability to hear who may communicate via sign language, spoken language, or both.

Hearing screening: a screening of the ability to hear selected frequencies at intensities above the threshold of normal hearing. The purpose of the screening is to identify (with minimal time expenditure) individuals with significant hearing loss and refer them for further testing.

Intensity: the loudness of a sound measured in decibels (dB).

Interpreter or transliterator for the deaf: a person who facilitates communication between hearing and deaf or hard of hearing persons through the interpretation of English into a signed language (e.g., ASL), the signed language into English, or the transliteration of a language into a visual/phonemic code by an oral interpreter or cued speech interpreter. A special kind of interpreter, the educational interpreter, specializes in classroom interpreting.

Intervener: an individual with knowledge and skills in the mode of communication of a student who is deafblind who can communicate to the student what is occurring in the educational setting.

Language: the comprehension (receptive) and/or use (expressive) of a spoken, written, and/or other signed (e.g., ASL) language.

  • ASL is a visual-spatial language used in the United States and Canada. The linguistic information is processed through the eyes and conveyed by the movement of the hands and non-manual signals. ASL has its own rules of grammar, phonology, morphology, semantics, syntax, and pragmatics.
  • Spoken and written language and their associated components are each a synergistic system comprised of individual language domains (phonology, morphology, syntax, semantics, pragmatics) that form a dynamic integrative whole (Berko Gleason, 2005).

Listening and spoken language therapy: application of techniques, strategies, and procedures that promote optimal acquisition of spoken language through listening.

Mixed hearing loss: a hearing loss that has a combined conductive and sensorineural component.

Morpheme: a linguistic unit of relatively stable meaning that cannot be divided into smaller meaningful parts.

Ophthalmologist: a physician specializing in the treatment of diseases of the eye.

Oral interpreter: a person who communicates the words of a speaker or group of speakers to an individual who is deaf by inaudibly mouthing what is said so that is can be read on his or her lips.

Otitis media: an infection of the middle ear. Children with recurrent episodes that are not appropriately treated may be at a higher risk for permanent decrease in hearing and/or may have a fluctuating hearing loss.

Otologist: a physician who specializes in the medical conditions of the ear.

Pragmatics: the appropriateness of language given the particular situation, speaker, and audience.

Progressive vs. sudden hearing loss: a progressive hearing loss is one that has decreased over time, such as a hearing loss resulting from a tumor on the auditory nerve, ototoxicity, or enlarged vestibular aqueduct syndrome (EVAS). A sudden hearing loss is one that has an acute or rapid onset and, therefore, occurs quickly, possibly caused by head trauma or a virus.

Residual hearing: the amount of usable hearing available for amplification purposes.

Reverberation: prolongation (continuation) of a sound after the sound source has ceased. The amount of reverberant energy in a room depends on the absorption quality of the material of the walls, floor, and ceiling.

Semantics: the use of meaningful referents, in both word and sentence structures.

Sensorineural hearing loss: a hearing loss that is caused by damage to some or all of the nerves in the cochlea. Sensorineural hearing loss causes both distortion and decreased loudness of sounds.

Signal-to-noise ratio: the difference in the intensities of the speech signal (e.g., the teacher's voice) and the ambient (background) noise

Speechreading (also referred to as lip reading): the interpretation of lip and mouth movements, facial expressions, gestures, and prosodic aspects of speech, structural characteristics of language, and topical and contextual cues.

Speech perception: the ability to recognize speech stimuli presented at supra-threshold levels (levels loud enough to be heard).

Speech intelligibility: the ability to understand speech (assessment); the ability to be understood when using speech (expressive).

Speech and word recognition: the ability to understand what is being spoken.

Syntax: defines the word classes of language (i.e., nouns, verbs, etc.) and the rules for their combination (i.e., which words can be combined, and in what order, to convey meaning).

Standards: grade-level expectations for students. Content standards are designed to encourage the highest achievement of every student by defining the knowledge, concepts, and skills that students should acquire at each grade level.

Symmetrical vs. asymmetrical hearing loss: symmetrical hearing loss means that the degree and configuration of the hearing loss are the same/similar in each ear. An asymmetrical hearing loss is one in which the degree and/or configuration of the loss is different in each ear.

Transition: this term is used in two situations. The first is when students are moving into the school system at age 3. The other use is for a coordinated set of activities that may address, among others, the assessment, planning process, educational and community experiences for youth with disabilities as they turn age 14. The intent of transition is to create opportunities for youth with disabilities that result in positive adult outcomes, including raising expectations, assessing interests, utilizing community supports, becoming involved in school and community activities, and fostering leadership development.

Unilateral hearing loss: may be a mild to profound loss of hearing in one ear. May adversely affect educational progress.