Download Powerpoint® Students with Deafblindess: An

Students with Deafblindess:
An Introduction
PowerPoint Slides
to be used in conjunction with the
Facilitator’s Guide
Copyright © 2012, East Carolina University.
Recommended citation:
Obold-Geary, R., & Henderson, K. (2012). Students with
Deafblindness: An Introduction– A PowerPoint
presentation for professional development. Module
Addressing Special Education and Teacher Education
(MAST). Greenville, NC: East Carolina University.
This resource includes contributions from the module
developer and MAST Module Project colleagues (in
alphabetical order) Kelly Henderson (Facilitator Guide
Editor), Tanner Jones (Web Designer), Diane Kester
(Editor), Sue Byrd Steinweg (Project Director), Bradley
Baggett (Graduate Assistant), and Sandra Hopfengardner
Warren (Principal Investigator).
Session Agenda
•
•
•
•
•
•
•
Deafblindness: An Introduction
Session Goal and Objectives
Vision and Hearing
Vision
Hearing
Definition of Deafblindness
General Characteristics of Deafblindness
Session Agenda, continued
• Educational Terminology Describing
Vision and Hearing
• Common Vision Disorders
• Common Hearing Disorders
• Causes of Deafblindness
• Assessment
• Summary
• Evaluation
Deafblindness: An Introduction
• Read this
email you
just
received
from
Principal
Johnson:
Introduction, continued
• After reading the email, you realize your
need to find out specific information about
the new student, but more importantly,
you want to learn more about
deafblindness (to calm the anxiety you
are most likely feeling!).
• Helen Keller might be the person with
deafblindness with whom you are most
familiar.
Introduction, continued
• Helen Keller’s experiences as a person of
deafblindness are not, however, typical of
all individuals who have this diagnosis. The
population of individuals with
deafblindness is quite heterogeneous.
• Each individual’s interaction with the world
depends on her degree of sight and
hearing.
Introduction, continued
• You might begin with questions:
– What is blindness and visual impairment?
– What does the world sound like with a hearing
impairment?
– What are some of the causes of
deafblindness?
– What does a person with deafblindness
experience?
Introduction, continued
• The term “deafblindness” will be used:
“In 1991, the International Association for the
Education of the Deafblind (now known as
Deafblind International) resolved to adopt this
spelling rather than use the hyphenated term
‘deaf-blindness’ to define the population of
infants, children and adults we are talking about
here. Although this change may not seem so
significant, it demonstrates that this is a unique
disability, and not the sum total of a vision and a
hearing loss” (Miles & Riggio, 1999, p. 22-23).
Introduction, continued
Before we begin, however, it is absolutely
critical to clarify the facts that:
• “Deafblindness” does NOT imply that an
individual sees or hears absolutely nothing.
• “Deafblindness” simply means that the
individual experiences both a vision loss
and a hearing loss, to some degree.
• Learners who have deafblindness are an
incredibly heterogeneous group!
Session Goal and Objectives
• In this session, participants will learn:
– definitions used in describing the sensory
systems of a learner with deafblindness;
– the various conditions and types of impairment
that are factors in understanding the impact of
sensory losses for an individual learner;
– the characteristics and needs of learners who
experience deafblindness; and
– strategies and techniques for supporting these
learners’ educational experiences.
Session Objectives, continued
Session ObjectivesThe participant will be able to:
1.identify definitions related to, and causes
and types of, combined visual and hearing
impairments (i.e., deafblindness);
2.identify terms related to visual impairment
or hearing impairment;
Session Objectives, continued
3. identify general characteristics that are
common among learners with
deafblindness;
4. identify the general needs of learners
who experience deafblindness;
5. identify elements critical to remember
when a person is communicating with a
learner who has deafblindness;
Session Objectives, continued
6. identify the characteristics relevant to
learning that are typical of children and
young adults with deafblindness;
7. identify critical strategies and techniques
that educational teams need to
implement when working with learners
with deafblindness; and
8. identify the critical nature of collaboration
for supporting learners who experience
deafblindness.
Vision and Hearing
• Our senses of touch, smell, taste, vision,
and hearing are critical to exploring,
learning, interacting, and functioning in
our daily environments.
• The eye and ear are fascinating sensory
organs; each is complicated in its
structure and function.
Vision and Hearing, continued
• In order to better understand the definitions
for deafblindness, it is important to
understand the basic anatomy and
functions of the typical eye and ear.
• Throughout this session, simulations will
be provided regarding types and degrees
of various hearing and vision losses.
Vision and Hearing, continued
• The simulations are just that—simulations.
They are an attempt to provide a brief
experience of what a condition might be
like.
• Each simulation is specific to a single
condition or description and does not
reflect the combinations of factors in any
individual learner’s experience.
Vision
• Vision is one of the senses that allows us
to gather information about our
environment and others around us.
– For example, the expression on a friend’s face
gives an indication of how he or she feels, and
road signs provide travel information.
• When people experience difficulty with
their vision, they may choose to have their
eyes examined by a doctor, who assesses
for visual acuity and visual field.
Vision, continued
Visual Acuity
• A visit to an ophthalmologist or optometrist
often includes a check of acuity.
– What is “normal” visual acuity? What is 20/20
acuity?
– Through research, doctors have determined
what a person, who has typical visual acuity,
should be able to see when standing 20 feet
away from an eye chart—without corrective
lenses (glasses).
Vision, continued
– Acuity of 20/20 means that when you stand 20
feet away from the Snellen eye chart, you can
see clearly, and with detail, what another
person without loss of visual acuity can see
(Cassin, Solomon, & Rubin, 1990; Heller & Kennedy, 1994).
– For reference, watch the simulation of normal
vision available at
http://www.acbvi.org/albums/Vision/slide2.html
. The first slide accessible from the link below
illustrates “normal,” 20/20, visual acuity.
Vision, continued
Visual Field
• Visual field is a second very important
feature when discussing vision.
• When looking straight ahead, at eye
level, the peripheral field is viewed to the
sides and above and below eye level
(Levack,
Stone, & Bishop, 1991).
Vision, continued
• Watch a simulation of peripheral loss:
http://www.acbvi.org/albums/Vision/slide5
.html.
• What is seen straight in front of you is the
central field. It is also possible to have a
visual loss in the central field
.
(Levack, Stone, & Bishop,
1991)
Hearing
• Processing sound provides information
about our social interactions and
surroundings. The sounds heard in
spoken language are a basis for learning
verbal language and communication.
• Hearing sounds, discriminating sounds,
and associating meaning with sounds
provides information about content
knowledge, directions, discussions, and
conversations with others.
Hearing, continued
• An audiologist is a professional trained to
test hearing. Following an assessment,
the audiologist charts an audiogram of
the levels and intensities of sounds an
individual “heard”.
• The audiogram is a visual representation
of a learner’s hearing levels.
Hearing, continued
• What do the terms “normal hearing” and
“hearing loss” mean?
• The loudness, or intensity, of sound is
measured in decibels (dB).
– Think of intensity as volume on a CD player.
Soft sounds such as whispering, or the
sound “t” in the word “too,” are examples. A
lawn mower and car horn are considered
loud sounds (American Speech-Language-Hearing Association, 2010).
Hearing, continued
• Normal hearing in children is defined as
the ability to hear sounds in the
“loudness” range of 0-25 decibels.
• In addition to intensity (loudness), a
second significant aspect of hearing
ability is the pitch, or frequency, of sound.
Hearing, continued
• Frequency is measured in Hertz (Hz).
– Frequency measures the pitch of low
frequency sounds, such as a tuba or the
speech sounds of “oo” in “who,” through the
entire range to high frequency sounds, such
as a bird chirp or the sound “s” in “sun.”
– Another way to think about pitch, or frequency,
is to consider a piano keyboard. Low
frequency sounds are on the left side of the
keyboard; high frequency sounds are on the
right hand side (American Speech-Language-Hearing Association, 2010).
Hearing, continued
• Examine the image “Audiogram depicting
‘normal’ hearing” on the next slide.
• This audiogram depicts “normal” hearing,
which shows both frequency and
intensity within the normal range.
Normal
hearing
Audiogram
showing
both
frequency
and
intensity
within the
normal
range
http://mast.ecu.edu/modules/db_int
ro/lib/documents/audiogram_01.pdf
Hearing, continued
• When talking about hearing under typical
conditions, the “speech banana” is often
referred to as the area of an audiogram
in which the sounds of human speech
are heard.
• Look at the diagram on the next slide that
illustrates which sounds are heard within
various frequency and intensity ranges.
http://speechbananas.com/
sample-page/
Hearing, continued
• Look at an audiogram on the next slide
that depicts a mild hearing loss.
– With this level of loss a learner can “hear,”
but will likely miss parts of a conversation
and may misunderstand portions of what is
said. A learner with a 40 dB loss might miss
as much as one-half of a class discussion
and / or might feel fatigued, due to the effort
involved in intently listening (Anderson & Matkin, 2010).
Mild
hearing
loss
http://mast.ecu.edu/modules/db_int
ro/lib/documents/audiogram_02.pdf
Hearing, continued
• The next audiogram illustrates a
moderate hearing loss.
• A learner with a moderate hearing loss
may understand a conversation held
within 3-5 feet. With a loss of 55 dB, the
learner may miss all spoken language
(Anderson & Matkin, 2010).
Moderate
hearing
loss
http://mast.ecu.edu/modules/db_intro
/lib/documents/audiogram_03.pdf
Hearing, continued
• Look again at the speech banana
illustration. Many sounds utilized in speech
and everyday activities could not be heard
in typical contexts or noisy environments,
even with only a mild hearing loss.
– Our hearing and vision greatly impact what we
are able to experience and access around us.
Take a moment to notice all the sights and
sounds around you and the information they
provide!
Hearing, continued
For more information about the anatomy of
the eye, ear, and the sensory systems,
please refer to the East Carolina University
Teacher Support Program at
http://www.ecu.edu/educ/ci/sped/dbproject/.
Hearing, continued
REMEMBER
• Visual acuity and peripheral vision are
critical in our daily lives.
• Typical speech sounds in a person with
“normal” hearing, vary both in intensity
and frequency.
• Both vision and hearing are critical to our
exploring, learning, interacting, and
completing the tasks of everyday living.
Definition of Deafblindness
• Several definitions are used in describing
deafblindness.
• Some definitions are medically related,
while others refer to the learner’s
functioning in the environment.
• Some terms reflect the need for support for
the individual’s unique learning
characteristics.
Definition, continued
• We’ll look at some common definitions
used when discussing the dual sensory
impairment, deafblindness.
– Some of these definitions might seem very
technical at first, but information included in
this session should help make these seem
less intimidating and more understandable.
Definition, continued
• “Legal blindness” refers to a central visual
acuity of 20/200 or less in the better eye
with corrective lenses, or a visual field loss,
such that the peripheral field is less than
20 degrees
.
• “Legal blindness” is not the only definition
pertinent to the field of visual impairment.
(Cassin, Solomon, & Rubin, 1990; Levack, Stone, & Bishop, 1991)
Definition, continued
• The Individuals with Disabilities Education
Improvement Act of 2004 (IDEA) describes
visual impairment and blindness as having
vision loss, even with correction, that
“adversely affects the educational
performance” of a learner.
• In IDEA, visual impairment is determined
by how the learner functions in the
environment and not solely on the basis of
a diagnosis or visual condition.
Definition, continued
• In IDEA, a “hearing impairment” is
described in educational terms as “an
impairment in hearing, whether permanent
or fluctuating, that adversely affects a
child’s educational performance.” A
hearing impairment may range from a mild
loss to a severe loss.
Definition, continued
• Deafness, as described in IDEA, is “a
hearing impairment that is so severe that
the child is impaired in processing linguistic
information through hearing, with or without
amplification” (IDEA, 2004).
Definition, continued
• The federal definition of deafblindness
recognizes the uniqueness of this disability:
– “Deaf-blindness means concomitant hearing
and vision impairments, the combination of
which causes such severe communication and
other developmental and educational needs
that they cannot be accommodated in special
education programs solely for children with
deafness or children with blindness.”
Definition, continued
• Thus, deafblindness requires its own
interpretation and bank of considerations,
when planning a learner’s educational
program.
• What then do these various definitions
really mean for a learner, families,
teachers, and others?
Definition, continued
• Barbara Miles writes about deafblindness :
“A person who is deaf-blind has a unique
experience of the world. For people who can see
and hear, the world extends outward as far as
his or her eyes and ears can reach. For the
young child who is deaf-blind, the world is
initially much narrower. If the child is profoundly
deaf and totally blind, his or her experience of
the world extends only as far as the fingertips
can reach. Such children are effectively alone if
no one is touching them” (2005, p. 1) .
Definition, continued
• Deafblindness affects two of a learner’s
three DISTANCE SENSES (i.e., vision,
hearing, and smell).
• It necessitates that she use IMPACT
SENSES (i.e., taste, touch, kinesthetic,
and proprioceptive) to gather information
from the environment
(Gee, Alwell, Graham, & Goetz, 1994)
Definition, continued
• Some learners have varying degrees of
vision and hearing. Regarding these
learners Miles adds:
“If a child who is deaf-blind has some usable
vision and/or hearing, as many do, her or his
world will be enlarged. Many children called
deaf-blind have enough vision to be able to
move about in their environments, recognize
familiar people, see sign language at close
distances, and perhaps read large print. …
Definition, continued
Others have sufficient hearing to recognize
familiar sounds, understand some speech, or
develop speech themselves. The range of
sensory impairments included in the term ‘deafblindness’ is great (Miles, 2005, p.1).”
Definition, continued
Given the wide variety of ways in which deafblindness presents, it is helpful to think about four
categories of deafblindness These four categories
include learners who are:
1) totally deaf and totally blind;
2) totally deaf, but able to use vision to some
degree;
3) totally blind, but able to use hearing to some
degree; and
4) able to use some residual hearing and some
residual vision (Miles & Riggio, 1999b and Heller & Kennedy, 1994) .
Definition, continued
• In addition, the time of onset of each
sensory loss (i.e., vision loss and hearing
loss) is of critical importance and must also
be considered.
– A “congenital” impairment refers to a loss that
is present at birth; an “adventitious” loss
develops at some point after the peri-natal
period. Congenital sensory loss generally has
a more pervasive effect on a child’s
development and future learning than do
adventitious sensory impairments.
Definition, continued
• The magnitude of the effect of an
adventitious hearing or vision loss will
depend on the individual’s age at the time
the sensory system becomes impaired
– For example, adventitious deafness will impact
the language development of a child who loses
her hearing at 15 months of age to a much
greater extent than it will affect the language
learning of a 7 year old child who becomes
deaf;
Definition, continued
– Adventitious vision loss will impact the 2-1/2
years old’s development to a much greater
extent than it will affect the development of
visual-motor skills and understanding of
visual-spatial concepts of a 10 year old child).
• The following table identifies conditions
associated with each of four categories of
deafblindness.
Category
Congenital Deafness –
Congenital Blindness
(i.e., Congenital
Deafblindness)
Adventitious Deafness –
Adventitious Blindness
(i.e., Adventitious
Deafblindness)
Congenital Deafness –
Adventitious Blindness
Congenital Blindness –
Adventitious Deafness
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Associated Conditions
rubella syndrome
• prematurity
cytomegalovirus (CMV)
• Leber syndrome
toxoplasmosis
• syphilis
Down syndrome
• herpes
CHARGE syndrome
• birth trauma
Fetal Alcohol syndrome
• toxins
Usher syndrome - Type III • trauma/head injury
meningitis
• stroke
encephalitis
• asphyxia
neurofibromatosis
• toxins
Friedreich’s ataxia
Usher syndrome – Type II
shaken baby syndrome
diabetic retinopathy
macular degeneration
Trisomy 13
infection/disease
trauma
Definition, continued
REMEMBER
• The timing at which an individual loses a
particular sensory ability is critical! This will
determine whether or not the individual
maintains visual imaging (of boundaries &
people) and/or recollection of sound.
Definition, continued
• A child with deafblindness is NOT:
– a “deaf child” who cannot see or
– a “blind child” who cannot hear.
• Deafblindness is a unique and complex
disability!
Activity - Definition
• Read pages 22 through 26 of
Understanding Deafblindness by B. Miles
and M. Riggio, available at
http://www.nationaldb.org/documents/rem
arkableconvchapt2.pdf.
• In your small group, adopt one deafblind
individual from the biographical sketches.
• Evaluate if and how the individual
challenges might impact your individual.
General Characteristics of
Learners with Deafblindness
• Since a learner with deafblindness has
different access to learning experiences
than do children who are typically
developing, deafblindness has been
described as a disability of information
gathering
.
(Gee, Alwell, Graham, & Goetz, 1994)
General Characteristics, continued
• Due to the impairments these learners
experience in their distance senses, they
often demonstrate several of the
following characteristics:
– difficulty bonding with caregivers and
establishing / maintaining interpersonal
relationships;
– feelings of vulnerability; generally, the
learner will experience feelings of greater
security/ safety in a seated position;
General Characteristics, continued
– difficulty developing skills for communicating
with others in a meaningful way;
– trouble learning object permanence (i.e.
knowing objects and people still exist when
they cannot be directly seen or heard) [not
fully understanding object permanence
greatly impacts learning];
– delayed understanding that there are
consequences to actions (i.e., “causality”)
because learners with deafblindness are not
able to see or hear “what happens”;
General Characteristics, continued
– inconsistent responses to sounds or visual
images (i.e., developing functional use of
remaining sensory skills can be difficult);
– developing a distorted perception of the
world (i.e., due to a lack of non-distorted
information from the distance senses); they
typically perceive time very differently (i.e.,
time seems to pass much more slowly);
– unusual responses via the impact senses
(e.g., tactile sensitivity or tactile
defensiveness, particularly around the face);
General Characteristics, continued
– an overactive startle response;
– difficulty interacting with things in the
environment in a meaningful way and/or
generalizing information;
– stereotypy (because of fear, confusion, and/ or
sensory deprivation); and
– delayed motor skills, such as crawling and
reaching (because these are motivated and
further developed by the use of vision and
hearing); difficulties interpreting movement;
problems in maintaining and restoring balance;
General Characteristics, continued
Learners who experience deafblindness
need:
– experiences for understanding concepts
through more than one sensory /
communicative mode (e.g., enhanced
textures);
– extra time (i.e., extended “wait time”) in
which to respond to another person’s
question / comment / interaction;
General Characteristics, continued
– to have the opportunity to learn and interact
in an enhanced context, in order to know
what is going on around them;
– extended periods of time to learn to trust
others and the external environment;
– assistance in order to counteract boredom;
– more frequent “breaks” to compensate for
the fact they typically fatigue more rapidly
than do their same-aged peers.
General Characteristics, continued
• So, how is all this information important?
• It is important to be able to understand a
learner, design an appropriate
educational program for her, assist
families, and educate communities to
embrace the talents and contributions
which individuals with deafblindness
offer.
General Characteristics, continued
REMEMBER
• Definitions of deafblindness vary
because of the degrees and severity of
the disability.
• Learners with deafblindness have a
disability in accessing and gathering
information.
General Characteristics, continued
• Deafblindness is not only a limitation of
hearing and sight. The combination of
these two sensory losses exponentially
affects all aspects of learning and daily
living.
Educational Terminology
Describing Vision and Hearing
VISION
• Vision loss occurs in varying degrees.
• Some terms used in the educational
setting when referring to vision loss:
– “low vision” refers to a significant vision loss,
but implies that the individual does still have
some usable vision for daily life. Moderate low
vision is defined as a visual acuity of 20/70 in
the better eye with corrective lenses;
Educational Terminology, continued
– “light perception” is the ability to differentiate
lightness from darkness. Some learners with
vision loss retain the ability to determine that
there is a source of light and from which
direction it is coming. Learners not having
light perception are considered to have “total
blindness” (Levack, Stone, & Bishop, 1991).
Educational Terminology, continued
HEARING
• When sound is heard, a person is
processing and interpreting a pattern of
vibrating air molecules
.
• Sound is measured in decibels (dB)
(loudness or intensity) and hertz (Hz)
(frequency or pitch). The range of normal
hearing is within 0-25 dB.
(Herer, Knightly, & Steinberg, 2002)
Category of Loss
Mild
Moderate
Moderate to Severe
Severe
Profound
dB Range
26-40 dB
41-55 dB
56-70 dB
71-90 dB
greater than 90 dB
Educational Terminology, continued
• With a mild hearing loss, most speech and
conversations can be heard; however,
sounds at a distance may be difficult to
hear.
• With a moderate hearing loss, hearing
normal conversation is difficult; therefore,
learning to hear speech sounds at a
young age, in order to develop clearly
articulated speech is a challenge.
Educational Terminology, continued
• A person with a severe hearing loss will
need an assistive hearing device, such as
a hearing aid, in order to hear speech and
conversation.
• Listen to simulated hearing loss samples:
http://www.cdc.gov/niosh/mining/topics/he
aringloss/hlsoundslike.htm.
– Follow the steps to first hear the “normal”
hearing simulation, then Moderate hearing
loss simulations.
Educational Terminology, continued
• Dr. Scott Bradley of the University of
Wisconsin has developed simulations of
severe to profound hearing loss. Listen at
http://facstaff.uww.edu/bradleys/radio/hlsi
mulation/ .
– Upon linking to the webpage, listen to the
“Normal Hearing” simulations. Then scroll
down to locate and listen to “Profound
Hearing Loss with Residual Low Frequency
Hearing.”
Educational Terminology, continued
• Look at an audiogram depicting severe
hearing loss on the next slide.
Severe
hearing loss
http://mast.ecu.edu/modules
/db_intro/lib/documents/audi
ogram_04.pdf
Educational Terminology, continued
• Several terms used in educational
settings include “deaf,” “hard of hearing,”
and “hearing impaired.”
• Even among professionals in the fields of
education and audiology, disagreement
exists regarding the most appropriate
definitions of these basic terms.
Educational Terminology, continued
– “Most audiologists reserve the term ‘deaf’ for
those individuals whose hearing loss is in the
profound range (hearing sounds only above 90
dB); below that level an individual would be
called ‘hearing impaired’ or ‘hard of hearing.’
Others use the term ‘deaf’ to describe any
person with a hearing impairment who does
not benefit from the use of hearing aids and/or
who uses sign language or other manual forms
of communication, regardless of the degree of
hearing loss” (Steinberg & Knightly, 1997, p. 247) .
Educational Terminology, continued
• The age of onset of a sensory impairment
is of critical importance
• The age of the learner when he or she
first experiences hearing loss or deafness
is critical to an understanding of his or her
possible exposure or non exposure to
verbal speech communication
.
(Heller & Kennedy, 1994)
Educational Terminology, continued
– For instance, learners who are congenitally
deaf will not hear spoken language and will
not, therefore, learn a communication system
based on oral language without intensive,
ongoing intervention and supports.
– A learner who becomes deaf later in
childhood or adolescence will have
experienced spoken language and will,
therefore, be more likely to retain at least a
degree of spoken language abilities.
Educational Terminology, continued
REMEMBER
• Common terms used in describing hearing
loss are deaf, hard of hearing, and hearing
impaired. The range of hearing loss varies
from mild to profound.
• Common terms used for vision loss include
low vision, light perception, or blindness.
• A learner experiencing deafblindness may
have some use of hearing and/or vision.
Activity - Educational Terminology
• The impact of hearing loss can be more
significant with background noise.
• Move to different areas of the facility.
Spend five minutes noting what types of
background noises are present, then report
back to a small group.
• In small groups, brainstorm options for
reducing the impact of these types of
background noises in your typical settings.
Common Vision Disorders
• Individuals wearing
glasses or contacts
probably are
corrected for some
of the most
common disorders
of visual acuity:
hyperopia, myopia,
and astigmatism.
Courtesy of the National Eye Institute, National Institutes of
Health (2010).
Vision Disorders, continued
• These occur when light rays entering the
eye do not fall on the retina in a way that
makes vision clear.
• Hyperopia, or farsightedness, occurs
when a learner sees things farther away
(i.e., greater than 14 inches) as unclear,
though closer objects are seen clearly.
When hyperopia is present, light rays fall
behind the retina.
Vision Disorders, continued
• Myopia, or nearsightedness, occurs when
a learner can see things more clearly up
close, but objects or images farther away
are unclear. When light rays fall in front of
the retina, myopia occurs.
• Astigmatism also causes vision to be
unclear because of a defect in the
curvature of the cornea.
Vision Disorders, continued
• In astigmatism, light entering the eye does
not focus on a single point on the retina,
thus affecting clear visual acuity.
• Visual field loss or severe restriction
constitutes a visual impairment.
• The central field is seen when looking
straight ahead, at eye level. Damage or
disorders affecting the macula of the eye
cause impairments to the central field of
vision.
Vision Disorders, continued
• The peripheral field is what can be seen
off to the sides of the body, while still
looking straight ahead.
• Some learners may have a condition
called “scotomas,” which are “blind
spots.” These scotomas may affect both
the central and/or peripheral vision.
• A simulation of scotomas is found at
http://www.acbvi.org/albums/Vision/slide1
2.html.
Vision Disorders, continued
Conditions resulting in muscle
imbalance
• Six muscles are attached to each eye.
When these muscles do not function
normally, conditions such as strabismus,
amblyopia, and nystagmus affect vision.
• Strabismus occurs when there is a muscle
imbalance and the eyes are not able to
“look” at an object at the same time.
Vision Disorders, continued
• Strabismus affects eye-hand coordination
and depth perception.
• Amblyopia occurs when only one eye is
used, which may cause field loss and/or
difficulties in depth perception.
• Nystagmus is caused by involuntary eye
movements, usually horizontally, though
the eyes may also involuntarily move
vertically, diagonally, and or circularly.
Vision Disorders, continued
• When a person experiences nystagmus, it
is difficult to maintain visual focus. There
may, also, be a decrease in acuity and/or
visual fatigue
.
(Heller & Kennedy, 1994; Levack, Stone. & Bishop, 1991)
Vision Disorders, continued
• The eye has outer, middle, and inner
layers.
• The cornea (on the outer layer of the eye)
helps refract, or bend, light rays entering
the eye.
• This bending is important and any
scarring or lesion of the cornea will affect
vision. If the cornea ruptures, blindness
may result
.
(Heller & Kennedy, 1994; Levack, Stone, & Bishop, 1991)
Vision Disorders, continued
Conditions affecting the middle eye
• Glaucoma and cataracts are conditions of
the middle eye.
• Glaucoma is caused by a blockage of fluid
in the aqueous humor of the eye. When
the fluid does not move correctly,
increased pressure results.
Vision Disorders, continued
• This pressure causes damage to the retina
of the eye and the optic nerve. Increased
pressure might cause fluctuating vision,
peripheral vision loss, poor vision at night
or in dark areas, difficulty reading or
seeing objects at a close distance, and/or
eye pain.
• When glaucoma is untreated, blindness
usually occurs
.
(Levack, Stone, & Bishop, 1991; Miller, Menacker, & Batshaw, 2002)
Vision Disorders, continued
• A cataract results in the “clouding” of the
lens of the eye. The lens focuses light onto
the retina. Cloudiness impedes the light
coming into the eye. Varying opaqueness
and location of a cataract impact the
degree of visual acuity.
Vision Disorders, continued
• Cataracts on the outer part of the lens
may result in difficulty discriminating
colors. Cataracts located more centrally
affect the central field of vision. Advanced
cataracts may cause blindness.
• The following are pictures of two
difference degrees or types of cataracts:
Courtesy of the National Eye Institute, National Institutes of Health (2010)
Vision Disorders, continued
Conditions affecting the inner eye
• Common disorders of the inner eye are
retinitis pigmentosa, retinopathy of
prematurity and retinal detachment.
• The retina gathers all the visual images
coming in through the cornea and lens. It
is made up of rods and cones and senses
light.
Vision Disorders, continued
• Rods make it possible for a person to see
in dim light, cones make it possible to see
color and details.
• In retinitis pigmentosa, the rods and cones
in the retina degenerate or lose their
effectiveness to gather specific visual
information.
Vision Disorders, continued
• When outer rods are affected, a learner
experiences peripheral field loss, or tunnel
vision. Due to the degeneration of rods,
some persons may have difficulty seeing
objects and persons at night and in the
periphery.
• When the cones in the middle of the retina
are affected, a learner has difficulty with
central vision and seeing colors.
Vision Disorders, continued
• As retinitis pigmentosa progresses, the
learner will have difficulty with tasks such
as reading and distinguishing details.
Watch a simulation of retinitis pigmentosa
at
http://www.acbvi.org/albums/Vision/slide1
5.html .
Vision Disorders, continued
• Babies born early may have retinopathy of
prematurity. Retinopathy of prematurity
(ROP) occurs when there is abnormal
blood vessel growth and development in
the eye.
• Blood vessels grow towards the middle of
the retina instead of growing along its
surface. This causes scarring on the
retina; the retina may detach.
Vision Disorders, continued
• If the retina becomes detached, severe
visual impairment or blindness will occur.
• Very young learners with retinopathy of
prematurity likely have decreased acuity
and visual field loss, in addition to other
possible visual impairments.
Vision Disorders, continued
Eye malformations affecting vision
• Several eye malformations are
associated with vision loss.
• Coloboma is caused when a child’s eye
does not form properly during pregnancy
so a gap, or cleft, exists in some part of
the eye.
Vision Disorders, continued
• When a coloboma occurs in the iris, a
learner may be sensitive to light since the
amount of light entering the eye may not
be adjusted properly by the iris opening
and closing in a typical manner.
• Depending on the location of the
coloboma in other parts of the eye, various
degrees of acuity and/or visual field loss
may occur
.
(Heller & Kennedy, 1994; Levack, Stone, & Bishop, 1991)
Vision Disorders, continued
• Cortical visual impairment (CVI) is a
neurological condition.
• In this condition, it is the brain and NOT
the eye that causes the visual
impairment. The eye and optic nerves
gather and send visual information
properly to the brain, but the brain is not
able to make sense of the information it
receives.
Vision Disorders, continued
• In CVI, the parts of the brain that process
visual information are not functioning
typically. The degree of vision loss
depends on the location of the impairment
within the brain, as well as age of onset.
• Cortical visual impairment may be mild to
severe, and either temporary or
permanent
.
(Roman-Lantzy, 2007)
Vision Disorders, continued
• It is typical for a learner with CVI to
demonstrate inconsistent visual
performance (i.e., to “see” something one
day, but not the next).
• Some of the characteristics of a learner
with cortical visual impairment include:
– using visual fields in individually unique ways
to view people and objects
– responding preferentially to colors, especially
yellow and/or red;
Vision Disorders, continued
– taking longer to look at something after it is
within view;
– experiencing difficulty with figure-ground
differentiation (i.e., seeing a specific item
when visual clutter is present in the
background);
– experiencing difficulty using vision and
reaching for something at the same time;
– needing an object to be moved slightly, to be
able to look at it for an extended period;
Vision Disorders, continued
– having a preference for seeing familiar
objects instead of new ones (Adapted from: Roman-Lantzy, 2007)
• Common causes of cortical visual
impairment include asphyxia (the brain
not getting enough oxygen), brain
hemorrhage, infections of the central
nervous system, and trauma to the brain.
Vision Disorders, continued
REMEMBER
• The type of eye condition impacts the
visual information received and processed.
• Cortical visual impairment is a condition in
which the brain is not able to adequately
interpret and use information sent by the
eye, through the optic nerves.
Vision Disorders, continued
• Premature birth may result in retinopathy
of prematurity, which can cause a variety
of visual conditions, including blindness.
Common Hearing Disorders
• Hearing loss is
typically classified
as one of three
basic types:
conductive,
sensorineural, and
mixed hearing loss.
Educational guide’s Weblog, 2008. Retrieved from:
http://educationalguide.files.wordpress.com/2008/09/
ear.jpg
Hearing Disorders, continued
• A conductive hearing loss occurs when
sound cannot pass through the outer ear to
the inner ear effectively.
• The outer ear and/or auditory canal may
have developed in such a way that sound
cannot travel to the inner ear.
• If the external part of the ear is blocked by
ear wax, fluid, or a tumor, a conductive
hearing loss can result.
Hearing Disorders, continued
• Otitis media, known as ear infection, can
result in a conductive hearing loss.
• During an episode of otitis media, fluid is
present in the middle part of the ear. This
fluid does not allow the tympanic
membrane, or ear drum, to move normally;
it may cause the eardrum to rupture.
Hearing Disorders, continued
• Damage to the middle ear may cause a
conductive hearing loss. If otitis media
occurs chronically, it may cause damage to
the ear and result in a sensorineural
hearing loss
• A sensorineural hearing loss is permanent.
It is caused by abnormal development or
damage to the cochlea and/or to the
auditory nerve.
(Heller & Kennedy, 1994; Herer, Knightly, & Steinberg, 2002).
Hearing Disorders, continued
• The cochlea, in the inner ear, is lined with
cilia, (or hair). Sound vibrations in the
cochlea bend the cilia; when the cilia bend,
they send signals to the auditory nerve.
The auditory nerve carries information
regarding sound to the brain.
• Sensorineural hearing loss may also occur
due to abnormalities in the auditory cortex
or brainstem.
Hearing Disorders, continued
• Auditory neuropathy spectrum disorder
(ANSD) is believed to characterize
approximately 10% of learners’
sensorineural hearing losses.
• In a learner with ANSD, sounds are
amplified satisfactorily in the cochlea, but
the portion of the brainstem devoted to
processing sounds does not respond
normally.
Hearing Disorders, continued
• This could be due to a problem “with the
connection between the inner hair cells (of
the cochlea) and the auditory nerve, or with
the auditory nerve itself”
.
• An impairment in the way a learner’s brain
processes auditory stimuli can result in
central auditory processing disorder
(CAPD).
(Morlet, 2010, p.2)
Hearing Disorders, continued
• As in cortical vision impairment, CAPD is
the brain and NOT the sensory organ (in
this case, the ear) that causes the
impairment.
• The outer, middle, and inner ear
components send auditory information
properly to the brain, but the brain is not
able to make sense of the information it
receives.
Hearing Disorders, continued
• The majority of learners who experience
CAPD do not “hear well in the presence of
competing speech or background
noise….They also have difficulty when an
important sound is degraded such as from a
badly tuned radio or through a bad phone
connection”
.
• CAPD may contribute to problems with
sound localization, discrimination, and the
ability to process quick sound sequences.
(Morlet, 2010, p.4)
Hearing Disorders, continued
• A mixed hearing loss is present when the
learner has both a conductive and
sensorineural hearing loss. Hearing loss
may also be unilateral or bilateral.
• With a unilateral hearing loss, there is
normal hearing in one ear and a hearing
loss in the other.
• Bilateral loss occurs in both ears, though
the sound intensities and frequencies heard
in each ear may be the same or different).
Hearing Disorders, continued
• In addition to their function as the organs for
hearing, the ears provide the sense of
physical balance, or equilibrium.
• A sense of balance helps us to know where
we are in space, helps us stand, run, and
walk without toppling over. Equilibrium is
controlled by the vestibular system in the
inner ears.
Hearing Disorders, continued
• The vestibular system sends messages to
the brain about body movement from side
to side and up and down. The vestibular
system involves hearing, vision, and the
feedback we get from our muscles.
• Because they experience both vision and
hearing losses, learners with deafblindness
typically have difficulty learning gross motor
skills and maintaining physical balance
(American
Speech-Language-Hearing Association, 2010).
Hearing Disorders, continued
REMEMBER
• Hearing loss may be conductive and/or
sensorineural. When both conductive and
sensorineural hearing losses are present,
the condition is referred to as a “mixed
hearing loss”.
• Sensorineural hearing loss is caused by
damage to, or poor development of, the
inner ear.
Hearing Disorders, continued
• Sensorineural loss also occurs when the
auditory nerves and/or the brain are not
able to receive and/or process information
from the outer, middle, and / or inner ear
properly.
• The ears and the eyes include components
of the vestibular system, which helps
maintain physical balance and body control.
Causes of Deafblindness
• A variety of known causes exist for
deafblindness; these include congenital
conditions and a wide variety of
conditions that occur, or manifest, after
birth (i.e., due to adventitious causes).
• Earlier in this session, a table listed
common causes of deafblindness
according to the time of an individual’s
life when the sensory loss occurred.
Causes of Deafblindness,
continued
• The following table provides additional
details regarding some of the most common
etiologies of deafblindness and sensory
conditions frequently associated with these
diagnoses.
Common Etiologies of Deafblindness
Etiologies of Deafblindness
Mechanism/Cause
Associated Sensory
Conditions
Sensorineural hearing loss,
retinitis pigmentosa
Usher Syndrome
(Types I, II, III)
Hereditary syndrome
CHARGE Syndrome
(coloboma, heart defect,
choanal atresia, retarded
growth, genital abnormalities,
ear abnormalities)
Retinopathy of Prematurity
(ROP)
Genetic pattern
Sensorineural hearing loss due
to malformed cochlea,
coloboma
Birth prior to full-term
Down Syndrome
Genetic pattern
Optic atrophy, cataracts,
glaucoma, underdeveloped
ears (causing sensorineural
loss)
Myopia, hyperopia,
strabismus, cataracts, mild to
moderate hearing loss
Syphilis, toxoplasmosis,
cytomegalovirus (CMV),
herpes, and human
immunodeficiency virus (HIV)
Infection
Various degrees of vision and
hearing loss
(Heller & Kennedy, 1994; Herer, Knightly, & Steinberg, 2002; Levack, Stone, & Bishop, 1991, Miller; Menacker, &
Batshaw, 2002)
Causes of Deafblindness, continued
REMEMBER
• Causes of deafblindness may be hereditary
or associated with prenatal, peri-natal, or
post-natal conditions.
• Infections transmitted from a pregnant
woman to her baby may cause dual sensory
loss.
• Premature infants are at a higher risk for
having difficulties with vision and hearing,
than are babies born at full-term.
Assessment
• An accurate assessment of a learner’s
vision and hearing is critical to determine
the medical and educational interventions
and instructional strategies needed for
each learner.
• Since each learner is unique, so must be
the assessment.
• Assessments may be formal or informal.
Assessment, continued
• An ophthalmologist will conduct a medical
evaluation for vision. Information gathered
will include the diagnosis, visual acuity, eye
muscle function, visual field, and the health
of each eye. If glasses are appropriate, they
will be prescribed.
• Additional information will be gathered by a
teacher of the visually impaired, with the
help of parents and other educational team
members.
Assessment, continued
• This is called a “functional vision
assessment.” During a functional vision
assessment, information will be collected in
regard to how the learner is able to use her
vision in everyday activities.
• Questions that will be addressed include:
– How close or far way to an object does the
learner need to be for vision to be helpful?
– What colors does the individual notice?
Assessment, continued
– How does the learner use her vision and
motor skills to move about?
– What kind of lighting is best for the learner?
• This information is collected in the
learner’s school and/or home settings and
is invaluable for designing instructional
programs and environmental
modifications
.
(Levack, Stone, & Bishop, 1991; Topor, 2009)
Assessment, continued
• Similarly, a hearing assessment will be
conducted.
• In most states infants are screened for
hearing impairments before leaving the
hospital after birth.
• Additional testing is needed if a baby does
not pass this screening.
Assessment, continued
• In the case of hearing losses that develop
later in life, assessments will be conducted
by an audiologist to determine if the loss is
conductive, sensorineural, or a mixed
hearing loss.
• To assess for intensity and frequency of
sounds a learner hears, the audiologist will
use a sound proof booth and a series of
activities to chart an audiogram.
Assessment, continued
• More sophisticated medical tests to
diagnose hearing loss include auditory
brainstem response & otoacoustic emission.
• A teacher of the deaf and hard of hearing, in
collaboration with others, may also conduct
a “functional hearing assessment.” This will
provide information about what the student
hears in common, everyday environments
and how she uses the hearing she has.
Assessment, continued
• Some of the questions addressed include:
– To what type of sounds does the learner
respond?
– What does the learner associate with sounds
heard?
– How does the learner respond when different
types of sounds are present in the
background? (American Speech-Language-Hearing Association, 2010; Durkel, 2005).
Assessment, continued
• Assessment information will help
determine the educational programming
and supports a learner needs.
• Areas addressed include: placement of
materials for best viewing, best positions
for hearing, assistive technology and
devices recommended, type of literacy
program, and systems / modes of
communication the learner needs.
Assessment, continued
Teaching learners with deafblindness
• Given all the information you have
processed previously in this module, it
should be becoming apparent that the
implications for teaching learners with
deafblindness are numerous.
• Remember that learners with deafblindness
often demonstrate the following
characteristics relevant to learning:
Assessment, continued
– lack of the ability to anticipate events;
– deprivation of many of the most basic extrinsic
motivations (i.e., curiosity), because sensory
information is often so distorted it is ineffective
as a source of motivation for exploring and
interacting with people and the environment;
– inability to benefit from being left alone, for long
periods of time, with toys or educational
materials;
– inability to benefit from incidental or secondary
learning;
Assessment, continued
– must be taught through direct, systematic
instruction;
– unlikelihood of independently learning from
mistakes, because she is unable to correctly
understand the results of her actions; and
– difficulty benefiting from group instruction,
alone, because she cannot learn optimally
from watching and listening to peers
Assessment, continued
• The best way to informally gauge a
learner’s cognitive skills is by observing the
way she “remembers”—that is, how she
deals with and what she does with the
sensory information she is able to process.
Assessment, continued
• Deafblindness requires a learner’s
educational team members to take time to:
– plan how she will RECEIVE information in
every activity;
– plan what the learner will DO in every activity;
– consider the IMMEDIATE physical, visual, and
auditory ENVIRONMENTAL CONTEXTS of
every activity.
Assessment, continued
• Educational teams need to include these
components in ALL routines, when working
with a learner with deafblindness:
– INITIATION (How will the learner know it is time
to begin a new activity?)
– PREPARATION (What does the learner need to
do in order to be ready for an activity?)
– CORE ELEMENTS (How, specifically, will the
learner participate in the activity?)
– TERMINATION (How will the learner know
when the activity is ending?)
Assessment, continued
Collaboration
• For a learner with deafblindness, neither
assessment nor instructional design can be
accomplished by one person or in isolation.
• Assessing, determining interventions, and
implementing best practice educational
strategies needs to be done collaboratively.
• Families of learners with deafblindness play
a critical in implementing strategies.
Assessment, continued
• The collaborating team may include:
– Parent and family, the ophthalmologist,
audiologist, otolaryngologist, and other medical
personnel, teacher of the blind and visually
impaired, low vision specialist, teacher of the
deaf and hard of hearing, special education
teacher, adapted PE teacher, paraprofessional,
intervener, general education teacher, speech/
language therapist, and orientation and mobility
instructor. A physical therapist, occupational
therapist, and nurse may also be included.
Assessment, continued
• Examples of educational considerations for
collaborative teams (which should include
family members of the learner):
Curriculum
– Access to the general education curriculum
– Literacy and numeracy
– Additional individual skills (e.g., orientation
and mobility)
– Communication
– Basic concept development
Assessment, continued
Instructional Strategies
– Systematic instructional methods
– Prompting and cueing strategies
– Wait time (time delay)
– Routines-based instruction
– Errorless learning
– Task analysis
– Individualized access to information and
experiences
Assessment, continued
Materials
– Assistive technology
– Low vision devices (e.g., magnifiers, CCTV)
– Assistive listening devices (e.g. hearing aids,
FM systems, cochlear implants)
– Adapted and alternate materials and tools
Assessment, continued
Environment
– Lighting
– Contrast
– Size of materials
– Learner’s positioning
– Distance
– Accessibility
– Background noise
– Visual background clutter
Assessment, continued
Other
– Time of onset of sensory losses
– Family preferences
– Learner preferences
– Family’s culture
– Presence of additional disabilities
– Medical conditions and / or interventions
– Medications
– Natural supports
(Gee, Allwell, Graham, & Goetz, 1994; Levack, Stone & Bishop, 1991; Miles & Riggio, 1999a). For additional
implications and considerations see additional MAST modules on Deafblindness.
Assessment, continued
REMEMBER
• Assessment information is obtained from
parents, medical professionals, and
educators observing and interacting with
the learner in daily activities & settings.
• Functional vision and hearing assessments
will address how the learner is currently
using vision and hearing in daily activities
and environments.
Assessment, continued
• Assessments will assist team members in
planning educational interventions and
instructional strategies.
• Collaboration among parents and
professionals is critical to obtaining reliable
assessment information and providing
best practice educational strategies for
learners with deafblindness.
Summary
• Definitions vary for classifying and
describing deafblindness.
• Most definitions do, however, emphasize
that such a unique dual sensory disability
profoundly impacts the learner’s access to
information, learning, and therefore, to
educational performance and engagement
in daily life.
Summary, continued
• A learner with deafblindness experiences
not only a vision loss and a loss of hearing,
but a unique experience of the concomitant
loss of these two senses.
• Deafblindness is a disability:
– about information gathering,
– which limits access, and
– that is exponentially more than a hearing loss
plus a vision loss.
Summary, continued
• To meet an individual learner’s needs,
assessments and collaboration among
families and professionals are essential.
• Partnering with a learner who experiences
deafblindness involves “inviting the child
(or adolescent) ‘out’ to join you in the
world” and building levels of connections
with her
(attributed to Jan van Dijk, in personal communication with Robbie Blaha, June 2006).
Focus and Reflection Questions
Divide the participants in groups of 3 or 4 and
discuss one of the following characteristics of
deafblindness relative to learning.
•
•
•
•
•
•
lack of the ability to anticipate events
deprivation of many of the most basic extrinsic motivations (i.e., curiosity),
because sensory information is often so distorted it is ineffective as a source
of motivation for exploring and interacting with people and the environment
inability to benefit from being left alone, for long periods of time, with toys or
educational materials
inability to benefit from incidental or secondary learning; must be taught
through direct, systematic instruction
unlikelihood of independently learning from mistakes, because she is unable
to correctly understand the results of her actions
difficulty benefiting from group instruction, alone, because she cannot learn
optimally from watching and listening to peers
Questions, continued
What questions have been raised that you
would like to discuss?
Application and Extension Activities
1. Divide the participants into pairs to go on a
“trust walk”. One partner is blindfolded
and the other becomes the leader for a
short walk in the hallway, returning in 5
minutes to the meeting room. Allow time
for discussion of feelings – of both the one
blindfolded and the helper. As time
permits, reverse the roles.
Application and Extension Activities
2. There are a variety of resources available to learn more
about deafblindness. There are agencies that serve the
needs of students and adults with deafblindness. The
resources listed are a few that are currently available.
Material Location:
http://nationaldb.org
http://www.hknc.org
National Consortium on Deaf-Blindness
Helen Keller National Center for Deaf-Blind Youths
and Adults
http://www.tsbvi.edu
Texas School for the Blind and Visually Impaired
http://www.wsdsonline.org Washington Sensory Disabilities Services
http://www.ncpublicschools.org/ec/instructional/deafblind/ North Carolina
Project for Children and Young Adults Who Are Deaf-Blind (Other state
projects are listed on the National Consortium of Deaf-Blindness website.)
Application and Extension Activities
Activity Steps:
1. Locate and become familiar with each of the websites
listed.
2. Discuss in a group and or plot on a chart the types of
Resources Topics
Commun- Transition
information available.
ication
Planning
Strategies and
3. Choose one of the
Services
resources. Develop a
summary detailing the
http:/.nationaldb.org
information provided and
present it or share it with a http://www.hknc.org
class or group of individuals. http://tsdbvi.edu
A sample chart to be
completed is on the right.
Instruction
al
Strategies
Self-Assessment
• A self-assessment with response feedback
is available at
http://mast.ecu.edu/modules/db_intro/quiz/
Participants may take this assessment
online to evaluate their learning about
content presented in this module.
Session Evaluation
• A form for participants to evaluate the
session is available in the Facilitator’s
Guide.