Persons with Hearing Impairments

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Chapter 11

• Persons with Hearing Impairments

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Definitions I

• Deafness a hearing loss that adversely affects
  educational performance and is so severe that the
  child is impaired in processing linguistic
  information, through hearing with or without a
  hearing aid (Kuder,2003)
• Hearing Impairment general term to describe
  disordered hearing and considered by some to
  imply deficiency

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Definitions II

• Hearing Sensitivity Loss a specific aspect of
  hearing impairment ranging in severity from mild
  to profound
• Residual Hearing remaining usable hearing
• Hard of Hearing the sense of hearing is less
  than optimal (residual)
• Minimal Hearing Loss (MHL) difficulty in hearing
  spoken language at a distance

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Deaf/deaf

• Deaf used with a capital D, refers to
  individuals who consider themselves members of a
  Deaf culture
• deaf refers to any hearing loss that is mild or
  moderate in degree

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Anatomy of the Auditory System

• Outer, middle, inner ear
• Tympanic membrane
• Ossicular chain malleus, incus, and stapes
• Cochlea
• Organ of Corti
• Central auditory nervous system
• Temporal lobe of the brain

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Figure 11.1 A Cross Section of the Human Ear
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Classification of Hearing Loss I

• Conductive blockage/barrier of mechanical sound
  conduction through outer or middle ear
• Sensorineural inner ear/auditory nerve disorder
  decreases impulse transmission to the brain
• Mixed Hearing Loss combination of conductive and
  sensorimotor loss

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Classification of Hearing Loss II

• Central Hearing Disorder disorder/dysfunction in
  the central auditory nervous system
• Auditory/neuropathy dy-synchrony absence of
  neural function with normal cochlea functioning.
• Functional/nonorganic inconsistent with
  audiometric testing

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Measurement of Hearing Loss

• Auditory threshold measures
• Audiogram
• Frequency measured in hertz (Hz)
• 250 Hz to 8000 Hz
• Human speech concentrates between 500-3000 Hz
• Hearing threshold levels (sound
  pressure/loudness) in decibels (dB)
• Human speech concentrates between 40-60dB
• Sounds above 130dB can be extremely painful and
  damaging

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SPEECH BANANA
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Audiometry

• Pure-tone stimuli delivered by earphones until
  test signal of particular frequency is barely
  audible (plots hearing thresholds)
• Air-conduction earphones or speakers used to
  test thresholds through outer, middle, and inner
  hear
• Bone-conduction small vibrator placed on
  forehead or bone behind the ear stimulates the
  inner ear directly

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Figure 11.2 Audiograms Demonstrating Types of
Hearing Loss
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Figure 11.2 Audiograms Demonstrating Types of
Hearing Loss
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Hearing Assessment

• Case history
• Anatomical inspection
• General audiometry
• Cognitive functioning
• Academic achievement
• Speech and language skills
• Speech recognition threshold
• Social-emotional adjustment
• Play audiometry
• Specialized evoked audiometry

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Prelingual v.Postlingual Hearing Loss

• Prelingual
• Present at birth
• Most common congenital disorder in newborns
• Neonatal universal hearing screening necessary to
  reduce effects of hearing loss on
  social/cognitive development
• Postlingual or adventitious
• Hearing loss occurs after acquisition of speech
  and language
• Impact on social/cognitive development dependent
  upon the childs age when the hearing loss
  occurred

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History of Persons with Hearing Impairments I

• 1817- American Asylum for the Education of the
  Deaf and Dumb
• Thomas Hopkin Gallaudet
• Brings Laurent Clerc to US from France
• A well known educator of the hearing impaired
• Used manual communication as his personal means
  of communication
• 1864- Abraham Lincoln signed legislation
  establishing Gallaudet University
• First college for the hearing impaired

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Gallaudet and BellOpposite Viewpoints

• Thomas Gallaudet
• Renowned legal scholar
• Promoted the manual method of communication for
  maximization of education and socialization
• Alexander Graham Bell
• Inventor of the telephone, internationally
  recognized educator of the deaf
• Believed manual method fostered segregation and
  sought to ban it in any form
• Strongly opposed residential schools, marriage
  between individuals who were both deaf, and
  letting adults with significant hearing loss
  become teachers of the deaf

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Prevalence

• 1.2 of all pupils with a disability
• 8,300 preschoolers receiving special education
  because of hearing impairments
• 70,767 students between 6 and 21
• 1 in every 22 infants born in the USA
• .011 of the total school age population

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Etiology

• Genetic/Hereditary
• Autosomal dominant
• Autosomal recessive
• X-linked recessive
• Infections
• Prenatal, perinatal, postnatal
• Developmental Abnormalities
• Environmental/Trauma

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Characteristics I

• Intelligence
• Similar to hearing with normal hearing a
  function of language development rather than
  hearing
• Speech and Language
• Mild to moderate loss and postlingual deafness,
  speech remains primary mode of communication
• Profound loss and prelingual deafness result in
  significant voice, articulation, and tone
  discrimination problems

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Characteristics II

• Social development
• Young children may exhibit less language
  interaction and imaginary play, more small group
  activity, little interest in playing with
  individuals who do not share a common
  communication system
• Older children need social and emotional growth
  opportunities to develop pragmatic abilities and
  friendships

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Educational Achievement

• May exhibit low academic achievement
• Three to four years delay
• Reading is most affected by a hearing impairment
• Median reading level for students ages 16-18
  with hearing impairment at 3rd grade level (Holt,
  1993)

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Assessment

• Cognitive- Must not rely primarily on verbal
  abilities
• Stanford Achievement Test- 91 of students with
  hearing loss are administered this test
• Communication- Must examine expressive and
  receptive communication skills in form, content,
  use of language
• Personal/Social/ Behavioral- Atypical responses
  may be due to linguistic differences

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Teacher To Do List

• Model and promote acceptance
• Be familiar with amplification devices
• Provide preferential seating
• Increase visual information
• Minimize classroom noise
• Structure lesson format to accommodate a hearing
  loss student
• Have realistic expectations

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Communication v. Language

• Communication
• Transfer of knowledge, ideas, opinions, and
  feelings
• Involves encoding and decoding messages
• Language
• Basis of communication
• System of rules governing sounds, words,
  meanings, and use

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Educational Approaches

• Bilingual-Bicultural
• Deaf culture
• ASL
• Total Communication
• Multiple communication techniques
• Sign language, fingerspelling, and speech reading
• Auditory-Oral
• Dependent on residual hearing, amplification, and
  speech/language training
• Spoken (oral) language

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Sign Language Systems(Kuder, 2003)

• American Sign Language
• Unique syntax system, used by interpreters
• Signing Exact English
• Similar to spoken English, uses English word
  order
• Signed English
• Uses ASL signs in English word order

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Technology

• Hearing/ Communication Aids
• Computers
• Alerting Devices
• Real Time Captioning/ Interpreting
• Telecommunication Devices
• Cochlear Implants

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Aids

• Hearing
• In-the-ear
• Behind-the-ear
• Body
• Bone-conduction
• Communication
• Assistive listening devices
• Auditory trainers
• Sound field systems

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Cochlear Implants

• A tiny array of electrodes
• Implanted surgically in the inner ear (cochlea)
• Attached to receiver-stimulator implanted just
  behind the ear at the base of the skull
• Individual wears a microphone and a small
  computer for speech processing, connected by
  electrical wiring
• Transmitter held in place over implant site by a
  magnet

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Transition Issues

• 1968- Pl 89-36 establishes Rochester Institute of
  Technology
• Mandated by IDEA 1990 and Section 504 of the
  Rehabilitation Act of 1973
• Funded by Congress at six post secondary programs
• Gallaudet University, NTID, California State, St.
  Paul Technical College, Seattle Community
  College, and University of Tennessee Consortium
• ( Lewis Greene, 1994)

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Adult Services

• State Commission or Office on Deafness
• Advocacy, information gathering, and
  dissemination, referral to appropriate agencies,
  interpreting services, and job placement and
  development
• State Vocational Rehabilitation Service
• Vocational evaluation, job placement, counseling,
  often in conjunction with high school transition
  planning

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Trends, Issues, and Controversies

• The merits of various methodologies
• Transitioning from child-centered to
  family-centered intervention programs
• Bicultural-bilingual philosophy
• Opposition to the total communication approach
• Emphasis on importance of early screening and
  timely and effective intervention programs
• Qualification of educational interpreters
• Limited cultural interaction between the Deaf and
  the hearing communities