Glossary Terms: A

A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z

Accommodations
Changes that allow a person with a disability to participate fully in an activity. Examples include extended time, different test format and alterations to a classroom.

Acoustics
Having to do with sound, the sense of hearing, or the science of sound. As used in this web site, the term refers to the qualities of an auditorium, classroom, or other space that determine how well sounds can be heard.

Acoustic Neurinoma
Tumor, usually benign, which may develop on the hearing and balance nerves and can cause gradual hearing loss, tinnitus, and/or dizziness. (sometimes called vestibular schwannoma). Also see Neurofibromatosis Type 2.

Acoustic Room Treatment
The use of sound-absorbing materials (such as carpets and acoustical tile) to reduce room noise and improve the usefulness of hearing aids and other listening devices.

Acquired Deafness
Loss of hearing that occurs or develops some time during the lifespan but is not present at birth.

ADA
Americans with Disabilities Act; landmark legislation protecting the rights of people with disabilities, including those who are deaf or hard of hearing.

ADD/ADHD
Attention deficit disorder and attention deficit hyperactivity disorder is a condition characterized by a child’s inability to focus, while possessing impulsivity, fidgeting and inattention.

ALDs
Assistive Listening Devices include FM Sound-field systems, amplified telephones, TTYs/TDDs, strobe light smoke alarms and alert systems, etc.

Adventitious Deafness
A hearing loss that occurs any time after birth due to injury or disease. 

Ageusia
Loss of the sense of taste.

Air Conduction 
An evaluative measure performed during diagnostic audiologic testing whereby sound is delivered via earphones through the ear canal, the ear drum, and middle ear to the inner ear to assess hearing sensitivity. (Contrasts with Bone Conduction, see below.)

Albinism
Lack of normal pigment in the skin, eyes, and hair.

Alport Syndrome
Hereditary condition characterized by kidney disease, sensorineural hearing loss, and sometimes eye defects.

American Sign Language (ASL)
Manual language with its own syntax and grammar, used primarily by people who are deaf.

Americans with Disabilities Act
Federal law that protects persons with disabilities from discrimination in the operation of public businesses and governments.

Amplification
The use of hearing aids and other electronic devices to increase the loudness of sound so that it may be more easily received and understood.

Anosmia
Absence of the sense of smell.

Aphasia
Total or partial loss of the ability to use or understand language; usually caused by stroke, brain disease, or injury.

Aphonia
Complete loss of voice.

Apraxia
Inability to execute a voluntary movement despite being able to demonstrate normal muscle function.

Articulation Disorder
Inability to correctly produce speech sounds (phonemes) because of imprecise placement, timing, pressure, speed, or flow of movement of the lips, tongue, or throat.

Assessment or Evaluation
Term used to describe all testing and diagnostic processes leading up to the development of an appropriate IEP for a student with special education needs.

Assistive Devices
Technical tools and devices such as alphabet boards, text telephones, or text-to-speech conversion software used to aid individuals who have communication disorders perform actions, tasks, and activities.

Assistive Listening Devices
A group of systems including personal hearing aids, FM systems and infared systems that through special input enhance listening situations and auditory awareness for use of the telephone, television, amplified alarms and signals. For more detailed information, see the sections on Support Aids and Auditory Devices.

Asperger’s Syndrome
Type of pervasive developmental disorder (PDD) that involves delays in the development of basic skills including socializing, coordination and the ability to communicate.

Atresia 
Closure of the ear canal and/or absence of an ear opening.

Audio Loops / Induction Loops 
Assistive listening device which enhances the use of hearing aids in schools, theaters, religious places, and public buildings and auditoriums. The ADA requires the inclusion of these systems in a host of public settings.

Audiogram 
A graph on which a person's ability to hear different pitches (frequencies) at different volumes (intensities) of sound is recorded.

Audiological Assessment 
A series of tests performed to identify pure-tone thresholds, impedance, speech recognition, and speech discrimination, which show the type and degree of hearing loss and status of outer, middle and inner ear function.

Audiological Evaluation 
Tests conducted by an audiologist to determine whether a hearing loss is present, what tones (pitches) are affected, how severe the hearing loss is, and the type of hearing loss. The evaluation also includes recommendations as to the hearing loss management, including selection of an appropriate amplification.

Audiologist 
Health care professional who is trained to evaluate hearing loss and related disorders, including balance (vestibular) disorders and tinnitus, and to rehabilitate individuals with hearing loss and related disorders. An audiologist uses a variety of tests and procedures to assess hearing and balance function and to fit and dispense hearing aids and other assistive devices for hearing.

Auditory Brainstem Response (ABR) Test  
A test for brain functioning in comatose, unresponsive, etc., patients, and for hearing in infants and young children; involves attaching electrodes to the head to record electrical activity from the hearing nerve and other parts of the brain.

Auditory Nerve
Eighth cranial nerve that connects the inner ear to the brainstem and is responsible for hearing and balance. 

Auditory Neuropathy
 Auditory neuropathy occurs when sound travels through to the inner ear normally, but the transmission of the auditory signals to the brain is impaired. Auditory neuropathy can affect children and adults, however incidences are low. People with auditory neuropathy generally have mild to severe hearing loss, and they always have poor speech perception no matter what level of hearing loss they have. Auditory Neuropathy can be very difficult to diagnose, especially in children when their hearing abilities appear to change back and forth. For more information on auditory neuropathy visit the National Institute on Deafness and Other Communications Disorders website. 

Auditory/Oral 
These programs teach children to make maximum use of their residual hearing through amplification (hearing aids or cochlear implants), to augment their residual hearing with speechreading, and to speak. This approach excludes the use of sign language.

Auditory/Oral Education 
An approach based on the principle that most deaf and hard-of-hearing children can be taught to listen and speak with early intervention and consistent training to develop their hearing potential. The focus of this educational approach is to use the auditory channel (or hearing) to acquire speech and oral language. The goal is for these children to grow up to become independent, participating citizens in mainstream society. Also known as Oral Deaf Education.

Auditory Perception
Ability to identify, interpret, and attach meaning to sound.

Auditory Prosthesis
Device that substitutes or enhances the ability to hear.

Auditory Trainer 
An assistive auditory device or FM system similar to a radio transmitter with a wireless microphone. The teacher or parent wears the microphone transmitter while the child wears the receiver which is set to amplify sound. The benefit is that the background room noise is not amplified, and the teacher/parent's voice has direct access to the child from any location, even another room.

Auditory Training 
The process of training a person's residual hearing in the recognition, identification, and interpretation of sound.

Auditory-Verbal
This approach is similar to the auditory/oral approach, except it does not encourage speechreading. This method emphasizes the exclusive use of auditory skills through one-on-one teaching. It excludes the use of any type of sign language, while emphasizing the importance of placing children in the regular classroom ("mainstream education") as soon as possible.

 Auditory/Verbal Therapists
The development of speech and verbal language through the maximized use of auditory potential by trained and licenced auditory/verbal therapists.

Augmentative Devices
Tools that help individuals with limited or absent speech to communicate, such as communication boards, pictographs (symbols that look like the things they represent), or ideographs (symbols representing ideas).

Aural Rehabilitation
Techniques used with people who are hearing impaired to improve their ability to speak and communicate.

Autoimmune Deafness
Individual's immune system produces abnormal antibodies that react against the body's healthy tissues.

Autism
A brain development disorder characterized by impaired social interaction and communication, and by restricted and repetitive behavior. Signs usually begin before a child is 3–years-old.

Autosomal
Describes genetic material (chromosomes or genes) that are not gender-related.