Hearing Disabilities

Learners Who Are Deaf or Hard of Hearing Overview- Isolation can accompany a hearing loss Controversy concerning whether children should be educated to communicate orally or through manual sign language Some do become fluent enough in spoken English to function in mainstream society Many members of the Deaf community consider themselves part of a cultural minority rather than disabled

Definition and Classification Decibels- units of relative loudness of sounds Congenitally deaf- deafness that is present at birth; can be caused by genetic factors Adventitiously deaf- deafness that occurs through illness or accident in an individual who was born with normal hearing Prelingual deafness- deafness that occurs before the development of spoken language Postlingual deafness- deafness occurring after the development of speech and language

Degrees of Hearing loss Mild- 26-54 db. Moderate- 55-69 db. Severe- 70-89 db Profound- 90 and above

Prevalence Differences in definition, populations studied, and accuracy of testing contribute to varying figures U.S. Dept. of Education estimate that about .14 percent of the population from 6-17 years of age is identified as deaf or hard of hearing

Anatomy and Physiology of the Ear The Outer Ear Tympanic membrane (eardrum)- Anatomical boundary between the outer and middle ears; the sound gathered in the outer ear vibrates here Auricle- The visible part of the ear; cartilage; collects sounds

The Middle Ear Ossicles- three tiny bones (malleus, incus, and stapes) that make a transfer of sound waves from the eardrum to the oval window Mallues- hammer-shaped bone Incus- anvil-shaped bone Stapes- stirrup Oval Window- The link between the middle and inner ears

The Inner Ear Vestibular mechanism- located in the upper portion of the inner ears; responsible for sense of balance Cochlea- snail-shaped organ that lies below the vestibular mechanism, converts the sounds into electric signals that are transmitted to the brain

Diagram of the ear

Measurement of Hearing Ability Screening Tests Otoacoustic emissions- low-intensity sounds produced by the cochlea in response to auditory stimulation; used to screen hearing problems in infants and very young kids Pure-Tone Audiometry- a test where tones of various intensities and frequencies are presented to determine a person’s hearing loss Speech Audiometry- technique that tests a person’s detection and understanding of speech

Tests for Young and Hard to Test Children Speech reception threshold (SRT)- the decibel level at which a person can understand speech Play audiometry- use of a game-like format to test hearing of young and hard to test children. Tympanometry- a method of measuring the middle ear’s response to pressure and sounds

Causes Conductive- transfer of sound in outer or middle ear Sensorineural- inner ear Mixed Hearing Loss- combination of both Hearing Loss and the Outer Ear External otitis-swimmer’s ear (infection) Hearing Loss and the Middle Ear Otitis media Hearing Loss and the Inner Ear Congenital cytomegalovirus

Psychological and Behavioral Characteristics English Language and Speech Development- English vs, ASL Intellectual Ability-difficulty in testing Academic Achievement-deficits Social Adjustment- based on communication

Educational Considerations Oral Approach: Auditory-Verbal Approach and Speechreading Total Communication http://www.masterstech-home.com/ASLDict.html The Bicultural-Bilingual Approach Service Delivery Models Technological Advances

Early Intervention Critical-language development-oral vs. manual Children with deaf parents develop language (ASL) faster

Transition to Adulthood Postsecondary Education Gallaudet University Traditional univrsities Family Issues 95% choose deaf spouses 90% of their offspring can hear