Download Understanding Students with Hearing Loss

Understanding Students
with Hearing Loss
Christa Simons, David Mangels, and Tammy Hall
Defining Hearing Loss
• The current regulations implementing IDEA define deafness as a
hearing impairment that is so severe that the student is impaired in
processing linguistic information through hearing, with or without
amplification, and that it adversely affects the student’s educational
performance.
• Deaf – hearing loss of 70 to 90 decibels (dB) or
greater
• Hard of Hearing – hearing loss in the 20 to 70
dB range
The Hearing Process
• When we hear sounds, we are really
interpreting patterns in the movement of
air molecules.
• Frequency – measured in hertz (Hz). Most of the
sounds we hear every day occur in the 250 to
6,000 Hz range
• Decibels – measures loudness (dB). Conversational
speech is usually at about 45 dB to 50 dB of
loudness.
Degrees of Hearing Loss
Types of Hearing Loss
• Conductive Hearing Loss happens when there is a problem
conducting sound waves through the outer ear, tympanic
membrane (eardrum) or middle ear (ossicles) and the inner ear
(oval window/round window). This type of hearing loss may occur
in conjunction with sensorineural hearing loss or alone.’
• Sensorineural Hearing Loss occurs when something damages the
inner ear, the auditory nerve, or the parts of the brain that process
sound. Sensorineural hearing loss includes both sensory and neural
hearing loss. Sensory hearing loss occurs when the cochlea, or tiny
hair cells, are damaged. Neural hearing loss happens when the
auditory or hearing nerve or the part of the brain responsible for
hearing is damaged.
• Mixed hearing loss is a combination of both conductive and
sensorineural hearing loss. Conductive hearing loss can commonly
be corrected with surgical or medical treatment, while sensorineural
hearing loss usually cannot be reversed.
Causes
• Genetic – hereditary loss can occur in
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approximately 1 in 2,000 children.
Prenatal – exposure to viruses, bacteria, and
other toxins before or after birth can result in a
hearing loss.
Postnatal – infections in infancy and childhood
also can lead to a hearing loss.
Postlingual – a blow to the skull can cause
trauma to the cochlea and may lead to a hearing
loss.
Determining the Presence of
Hearing Loss
Most states now have an Early Hearing Detection and Intervention (EDHI)
system, which is a process of screening for hearing loss.
1. Screens all newborns for potential hearing loss before 1 month of age,
and preferably before leaving the hospital.
2. Refers all infants who screen positive for a diagnostic audiologic
evaluation before 3 months of age.
3. Provides all infants identified as having a hearing loss with appropriate
early intervention services before 6 months of age.
Behavioral audiological evaluations are appropriate for testing the hearing
of older children. The child listens to a series of beeps called pure tones
and alerts the tester when she hears the sound. The child’s responses
are recorded on an audiogram, a picture of what is heard.
Other assessment measures…
Audiological re-assessment: Recent audiograms may indicate that the student’s
hearing loss has stabilized or is worsening. Testing for hearing aid function is a
regular need.
Speech and language evaluation: The student may have significant problems with
receptive and expressive language. The student’s speech is usually affected.
Individualized intelligence test: The student’s scores show a discrepancy between
verbal and nonverbal measures. Nonverbal tests are considered the only
reliable and valid measures of intelligence for this population.
Individualized achievement test: The student may score significantly lower than
peers.
Adaptive behavior: The student may score below average in communication and
possibly other areas of adaptive behavior.
Anecdotal records: The student’s performance may indicate difficulty with reading,
writing, or language arts.
Curriculum-based assessment: The student may be performing below peers in one
or more areas of the curriculum because of reading and/or language difficulties.
Direct observation: The student may be difficult to understand and may
misunderstand others.
Prevalence
• Students with hearing loss are considered a relatively small group
compared to other groups of students with disabilities.
– The U.S. Department of Education (2003) reported that 70,349
students with hearing loss between the ages of 6 and 21 received some
type of special education services in 2002-2003.
– The number of Americans with a hearing loss has doubled during the
past 30 years. Federal surveys illustrate the following trend of
prevalence for individuals aged three years or older: 13.2 million
(1971), 14.2 million (1977) 20.3 million (1991)
– 24.2 million (1993) 28.6 (2000).
– The number of children with disabilities ages 6-21 served in the public
schools under IDEA in the 2000-2001 school year was 5,775,722. Of
these children 70, 767 (1.2%) received services for hearing. However,
the number of children with hearing loss and deafness is undoubtedly
higher, since many of these students may have other disabilities as
well.
American Speech-Language Hearing Association
Communication
• Oral – subsequent amplification is used to emphasize sound to help the
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child use what hearing remains. Auditory training enhances the students’
listening skills and stresses using speech to communicate.
Manual – stresses the use of some form of sign language. This approach
makes use of the students’ intact visual modality to get information.
American Sign Language (ASL) is the most widely used sign language
among deaf adults in America.
Speech Reading – lip reading
Simultaneous communication – uses both sign language and lip reading
Cued Speech – the use of hand cues to supplement oral communication; it
helps the student distinguish between patterns of speech seen on the lips
Difficulty in communication
Students with hearing impairments do not hear speech, so they struggle to:
1. produce speech without assistance
2. produce proper volume, pitch, and nasality
Individual Hearing Devices
Hearing Aids
Hearing aids amplify sounds, but do not correct hearing. The behind the
ear aid is probably the most common type of hearing aid, used by both
children and adults. The case holding all of the components is worn behind
the ear, and the signal is delivered through a tube into the ear using an ear
mold. These hearing aids, in addition to their durability and flexibility, are
easier to keep track of and better equipped to withstand the wear and tear
of young children.
Cochlear Implants
A cochlear implant is an electronic device which
is surgically implanted under the skin behind
the ear and contains a magnet that couples to
another magnet in a sound transmitter that is
worn externally. A surgeon inserts an electrode
array into the cochlea to provide direct
stimulation to the nerve fibers. A speech
processor that can be worn on the body or
behind the ear is connected to a headpiece by a
cable. Sound is then picked up by a
microphone and sent to the speech processor,
which then filters, analyzes, and digitizes the
sound into coded electrical signals. These
coded signals are sent through a coil across the
skin to the internal implanted
receiver/stimulator via an FM radio signal. The
receiver delivers electrical stimulation to the
appropriate implanted electrodes in the cochlea,
and then the signal is carried to the brain
through the auditory nerve.
Classroom Accommodations
Assistive Listening Devices
Noisy environments, such as classrooms, disrupt the effects of most hearing aids.
Assistive listening devices that use FM radio frequencies, often referred to as FM
systems, are easily adaptable in this type of noisy scenario. The teacher wears a
wireless microphone, which allows both the student and teacher to move freely
within the classroom. The individual hearing aid will only pick up sound from the
microphone, however, and other discussions that are happening around them will
not be picked up unless the microphone is passed from teacher to student or student
to student.
General and Special Education
and Related Services
The 6 factors used in determining the nature and extent of
special education services for children who are deaf or
hard of hearing
a) Communication -includes evaluation
b) Academic achievement -indicated by classroom
performance and standardized tests
c) Socialization -how well the student interacts with others
d) Motivation - how motivated is the student for learning?
e) Parent expectations and preference - play a major role
in student achievement
f) Presence of additional disability - often, a student will
have more than one disability
Inclusion
a) 84% of deaf students are enrolled in the public
school system
b) Many deaf students are still not integrated in
the general education classroom
Meeting Students' Needs
A. Augmenting Instruction
1. Total Communication - The instruction is uses speech and sign language
together to help the student understand
2. Instructional conversations
a) The teacher uses conversational discourse
rather than the question/answer routine
b) The teacher focuses on concepts and content
while addressing language goals through:
1) Restating the idea
2) Clarifying the topic
3) Extending what the student response
B. Augmenting Curriculum
2 Goals when learning about deaf culture:
a) Help the fellow students develop an understanding of deaf
culture through learning and history lessons
b) Transmit culture to next generation of deaf students
C. Resources for the hearing impaired student:
1. Interpreters- Interpreters can interpret between English, ASL
transliteration, and other languages
2. Oral Transliteration- The translator mimics mouth movements
than sign language
rather
* this is generally utilized when the student is far away from speaker
3. Tools
a) Special Telephones
1) Teletype, aka: TTY- used to send messages
2) Text telephones- more modern; also used to
type rather than speak
3) Internet-can be used as a video phone online
b) CC- Closed captioning on T.V.
c) Alerting devices- vibrate and provide flashing lights for:
1) Alarm clocks
2) Doorbells
3) Smoke alarms
4) Phones
Learning Throughout Life
A. The best strategy for improvement is to catch
it early and provide treatment
B. Learning assistance is available for:
1. Early Childhood
2. Elementary
3. Middle/Secondary
4. Postsecondary- This is a good help for
those entering college. It provides help during
the transition.