DEFINING HEARING LOSS

hearing impairment the disability category label used in IDEA indicating a hearing loss for which special education and related services are needed

deaf not able to use hearing to understand speech even with a hearing aid, the hearing loss is too great to allow a deaf child to understand

speech through the ears alone although some sounds may be perceived through residual hearing, child uses vision as the

primary modality for learning and communication

hard-of-hearing a significant hearing loss that makes some special adaptations necessary can understand and respond to speech and other auditory stimuli, generally with the help of

a hearing aid speech and language skills, though they may be delayed or deficient, are developed mainly

through the auditory channel

conductive hearing loss abnormalities or complications of the outer or middle ear cause problems with transmitting sound vibrations to the inner ear

can often be corrected through surgical or medical treatment hearing aids are usually beneficial

T 10.1W. L. Heward, Exceptional Children, 6e, 2000 by Prentice-Hall, Inc. All rights reserved.

DEFINING HEARING LOSS (con’t)

sensorineural hearing loss caused by damage to the auditory nerve fibers or other sensitive mechanisms in the inner ear

sound delivered to the brain in a distorted fashion, or not delivered at all amplification--making the source of sound louder--may or may not help usually cannot be corrected by surgery or medication

unilateral hearing loss present in one ear onlybilateral hearing loss present in both earscongenital hearing loss present at birthadventitious hearing loss acquired later in life

prelingual hearing loss sustained before the development of spoken language; educational program focuses on acquisition of language and communication

postlingual hearing loss sustained after the development of spoken language; educational program usually emphasizes the maintenance of intelligible speech and appropriate language patterns

W. L. Heward, Exceptional Children, 6e, 2000 by Prentice-Hall, Inc. All rights reserved. T 10.2

CAUSES OF HEARING LOSS

Prelingual Causes maternal rubella (also known as German measles) can cause deafness, visual impairment, heart

disorders, and a variety of other serious disabilities when it affects a pregnant woman, particularly during the first trimester

heredity with the exception of rubella epidemics, genetic factors are the leading cause of deafness; more than 150 types of hereditary or genetic deafness have been identified

prematurity and complications of pregnancy early delivery and lower birth weight are more common among children who are deaf than among the general population

Congenital cytomegalovirus (CMV) a viral infection affecting 1% to 2% of all newborns, can result in several conditions, including mental retardation, visual impairment, and most often, hearing loss

Postlingual Causes meningitis the leading cause of adventitious hearing loss; a bacterial or viral infection that can

destroy the sensitive acoustic apparatus of the inner ear otitis media an infection or inflammation of the middle ear; if untreated, can result in a buildup of

fluid and a ruptured eardrum, causing permanent conductive hearing loss noise repeated exposure to loud sounds, such as industrial noise, jet aircraft, guns, and amplified

music, is increasingly recognized as a cause of hearing loss

Although several hundred causes of hearing loss have been identified, the exact cause is unknown for up to 50% of children with hearing loss.

W. L. Heward, Exceptional Children, 6e, 2000 by Prentice-Hall, Inc. All rights reserved. T 10.4

IDENTIFICATION AND ASSESSMENT OF HEARING LOSS

decibels (dB) standard unit for measuring the intensity of sound 0 dB represents the smallest sound a person with normal hearing can perceive; called the zero

hearing-threshold level (HTL), or audiometric zero a hearing loss of up to 25 dB is considered within the normal range

hertz (Hz) the frequency, or pitch, of sound measured in cycles per second humans can hear frequencies ranging from about 20 to 20,000 Hz the frequency range for hearing most spoken language is 500 to 2,000 Hz

pure-tone audiometry a formal testing procedure that determines how loud sounds at various frequencies must be before the child is able to hear them

child holds up a finger to signal when he hears a sound and lowers it when he hears no soundaudiometer an electronic device that generates sounds at different levels of intensity (dB) and frequency (Hz)

most deliver tones in 5 dB increments from 0 to 120 dB each dB level presented in various frequencies usually starting at 125 Hz and increasing in

octave intervals (doubling in frequency) to 8,000 Hzaudiogram a chart showing the results of an audiometric test

to obtain a hearing level on an audiogram, child must be able to detect a sound at least 50% of the time

W. L. Heward, Exceptional Children, 6e, 2000 by Prentice-Hall, Inc. All rights reserved. T 10.5

EFFECTS OF HEARING LOSS ON ENGLISH LITERACY AND ACADEMIC ACHIEVEMENT

A child with a hearing loss—especially a prelinguistic loss of 90 dB or greater—is at a great disadvantage in acquiring English language skills.

Hearing children typically acquire a large vocabulary and a knowledge of grammar, word order, idiomatic expressions, fine shades of meaning, and many other aspects of verbal expression by listening to others and to themselves from early infancy. A child who, from birth or soon after, is unable to hear the speech of other people will not learn speech and language spontaneously, as do children with normal hearing.

Since reading and writing involve graphic representations of a phonologically-based language, the deaf child must strive to decode and produce text based on a language for which he may have little or no understanding.

Deaf students typically have smaller vocabularies and their sentence structures are simpler and more rigid than those of hearing children of the same age or grade level.

Because the grammar and structure of English often do not follow logical rules (e.g., if the past tense of talk is talked, then why doesn't go become goed?), and a person with prelingual hearing loss must exert a great deal of effort to read and write with acceptable form and meaning.

The median grade level for reading comprehension of deaf students ages 16 to 18 years ranges from 2.9 to 3.2; for arithmetic computation, it ranges from 7.0 to 7.5.

Sign language—a visual-spatial language—is the first language for many deaf persons. Attempting to assess the intelligence of a deaf individual by his understanding and use of English—a phonologically based second language to which this person has had limited access—is just as inappropriate as using an English language assessment battery to classify a child whose first language is Spanish.

W. L. Heward, Exceptional Children, 6e, 2000 by Prentice-Hall, Inc. All rights reserved. T 10.7

ORAL/AURAL APPROACHES

Speech is viewed as essential if students who are deaf are to function in the hearing world. Training in producing and understanding speech and language is incorporated into virtually all aspects of the child's education.

used widely in the United States before the 1970s, a purely oral approach is now used by about one-fourth of educational programs for students with hearing loss

much attention is given to amplification, auditory training, speechreading, the use of technological aids, and, above all, talking

a few programs maintain a purely oral environment and may even prohibit children from pointing, using gestures, or spelling out words to communicate

a few oral programs use cued speech, a method of supplementing oral communication with hand signals near the chin to assist in identifying sounds that cannot be distinguished through speechreading

educators who use an oral approach acknowledge that teaching speech to children who are deaf is difficult, demanding, and time-consuming

most students with hearing losses no worse than severe can learn speech well enough to communicate effectively with hearing people

the best results are obtained with students in indisputably comprehensive oral programs or who are integrated most of the school day into regular education programs

W. L. Heward, Exceptional Children, 6e, 2000 by Prentice-Hall, Inc. All rights reserved. T 10.8

TOTAL COMMUNICATION

total communication the simultaneous presentation of manual communication (by signs and fingerspelling) and speech (through speechreading and residual hearing) to teach language to students with hearing loss

advocates believe it makes it possible for children to use either one or both types of communication, depending on the situation

since the 1960s, has become the predominant method of instruction in schools for the deaf teachers who practice total communication generally speak as they sign and make a special effort to follow the form and structure of spoken English

sign language use of gestures to represent words, ideas, and concepts some signs are iconic; they look like or appear to imitate or act out their message (e.g., the

signs for cat and eat) most signs, however, do not resemble the objects or actions they represent if sign language were simply a form of pantomime, then most nonsigners would be able to

understand it with relatively little effort

fingerspelling consists of 26 distinct hand positions, one for each letter of the English alphabet (see Transparency 10.10)

used to spell out proper names for which no sign exists and to clarify meanings

W. L. Heward, Exceptional Children, 6e, 2000 by Prentice-Hall, Inc. All rights reserved. T 10.9

AMERICAN SIGN LANGUAGE (ASL)

American Sign Language (ASL) is the language of the Deaf culture in the United States and Canada.

although sign languages by native deaf speakers were once thought of as non-languages, ASL is now viewed as a legitimate language in its own right

a visual-gestural language with its own rules of phonology, morphology, syntax, semantics, and pragmatics

the shape, location, and movement pattern of the hands; the intensity of motions; and the signer's facial expressions all communicate meaning and content

structured to meet eye and motor capabilities of the body; grammatical structure is spatially based

because ASL has its own vocabulary, syntax, and grammatical rules, it does not correspond to spoken or written English

difficult to make precise word-for-word translations between ASL and English

W. L. Heward, Exceptional Children, 6e, 2000 by Prentice-Hall, Inc. All rights reserved. T 10.11

BILINGUAL-BICULTURAL APPROACH

Proponents of a bilingual-bicultural approach view deafness as a cultural and linguistic difference, not a disability, and recognize American Sign Language (ASL) as the deaf child's natural language.

Both the Deaf community, as well as a growing number of hearing specialeducators, are calling for the use of ASL as the language of instruction.

They believe that ASL provides a natural pathway to linguistic competence and that English is better learned in the context of a bilingual-bicultural education after the child has mastered his or her native or first language (ASL).

The goal of the bilingual-bicultural education approach is for the deaf student to become a bilingual adult who is competent in both his or her first language, ASL, and can read and write with competence in his or her second language, English.

Empirical support for the bilingual-bicultural approach comes from some recent research finding that early exposure to and development of fluency in ASL are associated with increased competence and English literacy (reading and writing).

W. L. Heward, Exceptional Children, 6e, 2000 by Prentice-Hall, Inc. All rights reserved. T 10.12

AMPLIFICATION AND AUDITORY LEARNING

hearing aid a miniature amplification instrument that makes sounds louder

dozens of different kinds; can be worn behind the ear, in the ear, on the body, in eyeglasses can help many children by increasing their awareness of sound makes sounds louder but not necessarily clearer even the most powerful models do not enable children with severe and profound hearing losses

to hear speech sounds beyond a distance of a few feet does not cure a hearing loss or by itself enable a child who is deaf to function normally in the

classroom the earlier in life a child is fitted with an appropriate hearing aid, the better to derive the maximum benefit, must be worn throughout the day residual hearing is not developed by removing or turning the hearing aid off classroom amplification systems can augment the child’s personal hearing aid

auditory learning helps children make better use of residual hearing; includes four steps or levels:

awareness sensing the presence and absence of sound

localization locating the source of sound

discrimination differentiating between sounds

identification recognizing and comprehending the meaning of a sound

W. L. Heward, Exceptional Children, 6e, 2000 by Prentice-Hall, Inc. All rights reserved. T 10.13

SPEECHREADING

speechreading the process of understanding a spoken message by observing the speaker's face

traditionally called lipreading--some sounds are readily distinguished by watching the speaker's lips (e.g., the words pail and rail)

careful attention to a speaker's lips may help, but understanding speech from visual clues involves more than simply looking at the lips

important clues are obtained from signs or gestures, facial expressions, and familiarity with the context or situation

Speechreading is extremely difficult and has many limitations:

about half of all English words have some other word(s) that look alike on the lips (e.g., bat, mat, and pat)

visual clues may be blocked by a hand or a pencil, chewing gum, or a mustache many speakers hardly move their lips and are unintelligible through speechreading it is extremely tiring to watch lips for a long time it may be impossible to speechread at a distance, such as during a lecture even the best speechreaders detect only about 25% of what is said through visual clues alone

Despite the problems inherent in speechreading, it can be a valuable adjunct in the communication of a deaf or hard of hearing person.

T 10.14W. L. Heward, Exceptional Children, 6e, 2000 by Prentice-Hall, Inc. All rights reserved.