students with deafblindess: an introduction powerpoint slides to be used in conjunction with the...

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.


• 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.


• 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?


• 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).


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 Objectives-

The 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;


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;


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, continuedVisual 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 hearingAudiogram showing both frequency and intensity within the normal range

http://mast.ecu.edu/modules/db_intro/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


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


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.


• “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 (Cassin, Solomon, & Rubin, 1990; Levack, Stone, & Bishop, 1991).

• “Legal blindness” is not the only definition pertinent to the field of visual impairment.


• 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.


• 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.


• 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).


• 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.”


• 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?


• 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) .


• 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)


• 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. …


Others have sufficient hearing to recognize familiar sounds, understand some speech, or develop speech themselves. The range of sensory impairments included in the term ‘deaf-blindness’ is great (Miles, 2005, p.1).”

Definition, continuedGiven the wide variety of ways in which deaf-blindness 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) .


• 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.


• 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;


– 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 Associated ConditionsCongenital Deafness – Congenital Blindness(i.e., Congenital Deafblindness)

• rubella syndrome• cytomegalovirus (CMV)• toxoplasmosis• Down syndrome• CHARGE syndrome• Fetal Alcohol syndrome

• prematurity• Leber syndrome• syphilis• herpes• birth trauma• toxins

Adventitious Deafness – Adventitious Blindness(i.e., Adventitious Deafblindness)

• Usher syndrome - Type III• meningitis• encephalitis• neurofibromatosis• Friedreich’s ataxia

• trauma/head injury• stroke• asphyxia• toxins

Congenital Deafness – Adventitious Blindness

• Usher syndrome – Type II• shaken baby syndrome• diabetic retinopathy• macular degeneration

Congenital Blindness – Adventitious Deafness

• Trisomy 13• infection/disease• trauma


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.


• 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/remarkableconvchapt2.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;


– 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”;


– 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);


– 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;


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;


– 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.


• 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.


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.


• 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).


HEARING

•When sound is heard, a person is processing and interpreting a pattern of vibrating air molecules (Herer, Knightly, & Steinberg, 2002).

•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.

Category of Loss dB Range

Mild 26-40 dB

Moderate 41-55 dB

Moderate to Severe 56-70 dB

Severe 71-90 dB

Profound greater than 90 dB


• 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.


• 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/hearingloss/hlsoundslike.htm. – Follow the steps to first hear the “normal” hearing

simulation, then Moderate hearing loss simulations.


• 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/hlsimulation/ . – 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.”


• Look at an audiogram depicting severe hearing loss on the next slide.

Severe hearing loss



• 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.


– “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) .


• 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).


– 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.


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.


• 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.


• 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/slide12.html.


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.


• 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.


• 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).


• 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).


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.


• 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) .


• 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.


• 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, continuedConditions 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.


• 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.


• 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.


• 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/slide15.html .


• 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.


• 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.


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.


• 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).


• 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.


• 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).


• 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;


– 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;


– 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.


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.


• 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.


• 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.


• 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 (Heller & Kennedy, 1994; Herer, Knightly, & Steinberg, 2002).

• A sensorineural hearing loss is permanent. It is caused by abnormal development or damage to the cochlea and/or to the auditory nerve.


• 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.


• 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.


• 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” (Morlet, 2010, p.2).

• An impairment in the way a learner’s brain processes auditory stimuli can result in central auditory processing disorder (CAPD).


• 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.


• 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” (Morlet, 2010, p.4).

• CAPD may contribute to problems with sound localization, discrimination, and the ability to process quick sound sequences.

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).


• 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.


• 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).


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.


• 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.

Etiologies of Deafblindness Mechanism/Cause Associated Sensory Conditions

Usher Syndrome (Types I, II, III)

Hereditary syndrome Sensorineural hearing loss, retinitis pigmentosa

CHARGE Syndrome(coloboma, heart defect, choanal atresia, retarded growth, genital abnormalities, ear abnormalities)

Genetic pattern Sensorineural hearing loss due to malformed cochlea, coloboma

Retinopathy of Prematurity (ROP)

Birth prior to full-term Optic atrophy, cataracts, glaucoma, underdeveloped ears (causing sensorineural loss)

Down Syndrome Genetic pattern 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

Common Etiologies of Deafblindness

(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.


• 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?


– 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).


• 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.


• 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.


• 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.


• 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 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.


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:


– 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; and

– difficulty benefiting from group instruction, alone, because she cannot learn optimally from watching and listening to peers


• 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.


• 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.


• 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?)


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.


• 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.


• 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


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


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


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.


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.


• 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 QuestionsDivide 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.


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 National Consortium on Deaf-Blindnesshttp://www.hknc.org Helen Keller National Center for Deaf-Blind Youths and Adultshttp://www.tsbvi.edu Texas School for the Blind and Visually Impairedhttp://www.wsdsonline.org Washington Sensory Disabilities Serviceshttp://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.)


Resources Topics Commun-icationStrategies

Transition Planning and Services

Instructional Strategies

http:/.nationaldb.org

http://www.hknc.org

http://tsdbvi.edu

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 information available.

3. Choose one of the resources. Develop a summary detailing the information provided and present it or share it with a class or group of individuals. A sample chart to be completed is on the right.

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.

students with deafblindess: an introduction powerpoint slides to be used in conjunction with the...

Documents

person of deafblindness

term deafblindness

causes of deafblindness

deafblindness experience

session agenda deafblindness

introduction session

hearing impairment

facilitators guide slide