visual impairment and characteristics

8/10/2019 Visual Impairment And characteristics

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Q: Characteristics of a Visually Impaired Child

Definition

A visual impairment is any visual condition that impacts an individual’s ability to

successfully complete the activities of everyday life. Students with visual

impairments are infants, toddlers, children and youths who experience

impairments of the visual system that impact their ability to learn.

There are three classification systems for individuals with visual impairment that

are used by education professionals. To be declared legally blind, an individual

must have visual acuity of 20/200 or less, or have a field of vision restricted to 20

degrees or less at the widest point. However, this federal classification system is

used primarily to determine eligibility for adult agency services.

For educational purposes, a specially trained teacher must determine that the

visual impairment impacts the child’s ability to learn, and this professional

determination, with the agreement of the IEP team ensures access to special

education services. To implement appropriate classroom accommodations for

students with visual impairment, these students are also classified according to

their level of functional vision:

Low vision – students use their vision as their primary sensory channel

Functionally blind – students can use limited vision for functional tasks but

need their tactile and auditory channels for learning

Totally blind – students use tactile and auditory channels for learning and

functional tasks

A third classification system exists is based on the advent of the visual

impairment itself:

Congenital – occurs during fetal development, at birth or immediately

following birth; visual impairment is present before visual memory has beenestablished

Adventitious – occurs after having normal vision either through a hereditary

condition or trauma; visual memory may remain.

Students with congenital visual impairment typically have more difficulty

mastering visually strengthened concepts such as spatial orientation and many

environmental concepts



PrevalenceIt is difficult to obtain an exact prevalence of visual impairment due to the often

hidden nature of visual impairment in special education. Many students with

visual impairments also have additional coexisting impairments and are thus

classified in an alternate disability category. The National Dissemination Center

for Children with Disabilities reports that the rate of occurrence for visual

impairments in individuals under the age of 18 is at the rate of 12.2 per 1,000.

Legal or total blindness occurs at a rate of .06 per 1,000. Current specialeducation demographics obtained from the American Foundation for the Blind

2009 report that there are:

93,600 students who are visually impaired or blind;

55,200 students who are legally blind;

5,500 Braille readers

Characteristics of a Visually Impaired Child

It is not always easy to recognize that a child might be visually impaired. Although even

very young children can show some physical signs of having trouble with vision, many

times problems with a child's eyesight are not detected until after he goes to school. The

American Optometric Association points out that because 80 percent of a child's

learning relies on his vision acuity, early detection and treatment are needed.

Physical Signs

Crossed eyes, eyes that turn out, eyes that flutter from side to side or up and down, oreyes that do not seem to focus are physical signs that a child has vision problems.

Other problems are less obvious. The American Academy of Pediatrics recommends

that children have their eyes checked during regular well-baby visits throughout their

first years. A child should have a routine eye exam every year beginning at age 5.

Clumsiness A child might have a vision problem if he appears to be overly clumsy. Poor vision might

be the cause when a child is constantly running into things or falling down. He might

have trouble realizing how close or far away objects really are. The eyes provide the

information about surroundings and spatial position that is transmitted to the brain.

Consequently, clumsiness can occur when the eyes misjudge a distance. Sometimes

young children who do not walk well actually have problems with their vision.

BehaviorSome children who have vision problems appear to have a short attention span. Other

children might blink frequently or squint whenever they read or watch television. Often



children are sensitive to bright light or might sit close to the television or hold books that

they are reading close to their face. Likewise, younger children with visual impairments

might hold toys very close to their face.

Poor Eye-Hand CoordinationPoor eye and hand coordination can be another sign that a child has a vision problem,

therefore parents should observe a young child as he plays. Older children who go to

school might have difficulty with sporting activities or certain projects in class. Signs of

poor eye-hand coordination might include difficulty throwing or catching a ball, tying

shoes or copying schoolwork from the blackboard. Poor handwriting is often another

sign of poor eye-hand coordination. Children who suffer from lazy eyes, crossed or

wandering eyes can have problems with coordination, balance and depth perception,

primarily because they learn to use only one eye at a time.

Poor Academic PerformanceChildren who have trouble seeing often perform poorly at school. Frequently, problems

with learning are actually related to poor vision and not to a learning disability. A child

might not read well, or might use her finger to follow along when she is reading so that

she doesn't lose her place. Some children also have trouble remembering what they

read. Children with vision problems can find it difficult to write as well or might have

problems with math and other subjects. Schoolwork can be a challenge for a child who

cannot keep a clear focus, deals with double vision or blurred print on pages.

Unfortunately, not all vision problems are easily detectable. For children who have had

vision problems from the start, their vision seems perfectly normal to them, so they don't

usually complain.

CharacteristicsVisual impairment is essentially an umbrella term used to describe the loss of

sight that can be a consequence of a number of different medical conditions.

Some common causes of visual impairment are glaucoma, retinopathy of

prematurity, cataracts, retinal detachment, macular degeneration, diabetic

retinopathy, cortical visual impairment, infection and trauma. These are just a

handful of dozens of conditions impacting sight, and each condition has its own

unique characteristics and clinical features. In addition, the impact of the visual

impairment on individual learning is also tied to the onset, the severity, and the

type of visual loss, as well as to any coexisting disabilities that may be present in

the child. For this reason, all classroom accommodations, modifications, and

strategies must be designed with the individual needs of each student with a

visual impairment in mind. There is no one-size-fits-all model.



In addition to decreased visual acuity and visual field, a number of other vision

problems may also impact the visual functioning of the student with visual

impairment. There may be issues with sensitivity to light or glare, blind spots in

their visual fields, or problems with contrast or certain colors. Factors such as

lighting, the environment, fatigue, and emotional status can also impact visual

functioning in many of these students throughout the day. Students who have the

same visual condition may use their sight quite differently. To ensure accessibilityto classroom instruction, it is essential that you know how your student is using

his/her vision. A specially trained teacher of students who have visual

impairments, working with the IEP team members, can help determine the best

adaptations and learning media to use with each student.

Impact on LearningOne characteristic that is shared by all students with visual impairment is that

these students have a limited ability to learn incidentally from their environment.

It is through sight that much of what we learn is received and processed. It isbelieved that up to 80% of what children without visual impairments learn is

through visual cues. The other senses do not fully compensate for the loss of

sight. Touch and hearing can be ineffective substitutes for many individuals.

Children with visual impairments must be taught compensatory skills and

adaptive techniques in order to be able to acquire knowledge from methods other

than sight. The presence of a visual impairment can potentially impact the normal

sequence of learning in social, motor, language and cognitive developmental

areas.

Reduced vision often results in a low motivation to explore the environment,

initiate social interaction, and manipulate objects. The limited ability to explore

the environment may affect early motor development. These students cannot

share common visual experiences with their sighted peers, and therefore vision

loss may negatively impact the development of appropriate social skills. As a

result, these students may experience low self-esteem that limits their sense of

mastery over their own lives.

It is not enough to just provide instruction in the general core curriculum.

Students with visual impairments also need specialized instruction in a number of

other essential skill areas. These areas, called the expanded core curriculum,

include communication skills, social interaction skills, orientation and mobility,

independent living skills, recreation and leisure skills, use of assistive technology,



visual efficiency, and career education skills, and self-determination. Mastery of

these skills is essential for students’ long-range educational and life outcomes.

Students with visual impairments can learn at roughly the same rate as other

children but require direct interventions to develop understanding of the

relationships between people and objects in their environment.

Teaching StrategiesClassroom accommodations will be quite varied and should be individualized

according to the specific needs of the student. However, there are some basic

best practices that can guide the development of the most effective adaptations.

One thing to always consider is that it is often difficult for these students to

become as fully independent as they are capable of being. The classroom

teacher should encourage independence as often as possible to avoid the trap of

―learned helplessness.‖ Encourage the student to move independently throughthe classroom, and organize your classroom accordingly. Materials, desks, and

other objects in the classroom should be maintained in consistent locations.

Ensuring that cabinets are fully closed, chairs pushed in, and doors are not left

half ajar will help with safety in navigating the classroom. Part of becoming

independent for students with a visual impairment is learning when to advocate

for assistance. Not all instructional tasks will be immediately possible for a

student with a visual impairment, even with accommodations. The key is to

design your instruction so that the student has the most opportunity to act

independently. The student’s orientation and mobility specialist and teacher ofstudents with visual impairments can assist with room arrangements and room

familiarization.

Adapting your classroom to accommodate a student with a visual impairment is a

relatively easy task—it just requires an awareness of the student’s level of visual

functioning (how the student sees) and how the student works and learns. For

example, for the student with low vision, make sure that he is near the front of the

room where he can see the blackboard. Control lighting variables when

presenting learning materials to those students who are sensitive to light and

glare. Use verbal cues with those students who cannot see body movements or

physical cues. A trained teacher of students visual impairments can help you

make a few simple changes to classroom design that may mean all the

difference in the education of the student with a visual impairment.



One key accommodation that is absolutely essential is access to textbooks and

instructional materials in the appropriate media and at the same time as their

sighted peers. For students who are blind this may mean braille and/or recorded

media. For the student with low vision, this may mean large print text or the use

of optical devices to access text and/or recorded media while in class. Working

closely with a student’s teacher of students with visual impairments in advance

helps ensure accessible materials and availability of these materials in a timelymanner.

Assistive TechnologyIn order to access print information, students with visual impairments must be

trained in the use of a number of adaptive devices, methods, and equipment that

are collectively referred to as assistive technology. Some of this technology

allows access to information presented on a computer while others are devices

to be used independently. Computer hardware and software are continuously

advancing, allowing for more access to information than ever before. Someexamples:

Computer adaptations:

Braille translation software and equipment: converts print into braille andbraille into print.

Braille printer: connects to a computer and embosses braille on paper.

Screen reader: converts text on a computer screen to audible speech.

Screen enlargement software: increases the size of text and images on acomputer screen.

Refreshable Bbraille display: converts text on computer to braille by an outputdevice connected to the computer.

Adaptive devices:

Braille notetakers: lightweight electronic note-taking device that can beconnected to a printer or a braille embosser to produce a printed or brailledcopy.

Optical character reader: converts printed text into files on a computer thatcan be translated into audible speech or Braille with appropriate equipmentand software.

Electronic braillewriter: produces braille, translates braille into text or syntheticspeech.

Talking calculators: calculates with voice output.

Optical devices:



Closed Circuit Television (CCTV): enlarges an image to a larger size andprojects it on a screen

Magnifiers: enlarges images

Telescopes: used to view distant objects

A specially trained teacher of students with visual impairments can help supply

many of these devices and can provide training for the student to become

independent and proficient in using assistive technology.

Low Vision: If someone's vision is between 20/70-20/160 and cannot be corrected,

the student has moderate to low vision.

Legally Blind: From 20/200-20/400 is legally blind with severe low vision. From

20/400-20/1000 is profound visual impairment, and is very close to total blindness.

Totally Blind: The lack of light perception is known as total blindness or total visual

impairment.

Refractive ErrorsThe most common types of visual impairments are simple refractive errors. These

include nearsightedness, farsightedness, and astigmatism. In nearsightedness images

are focused in front of the retina, making far away images appear blurry.

Farsightedness results from an image being focused behind the retina, which means

the child will have trouble focusing on objects that are close up. Astigmatism results

from curvature of the cornea, which keeps light rays from focusing properly in one area

of the retina. This condition results in the inability to focus on objects far or near.

Fortunately, refractive errors are correctable. Many children use glasses and enjoy clear

vision. These students will have no need for special services unless the refractive error

is not correctable for some reason.

Common Eye Conditions

Amblyopia:

Amblyopia is also known as lazy eye. Children with a lazy eye may or may not beperceptible. Sometimes a lazy eye visibly turns in or out, but sometimes there is no

outward sign. Amblyopia causes the eye to have reduced acuity due to the poor

positioning of the eye and weak muscles. The treatment is commonly a patch over the

normal eye that makes the lazy eye work harder. Surgical corrections are also common.

Retinitis Pigmentosa:

This is a degenerative condition that is inherited. Retinitis pigmentosa results in a loss of

peripheral vision, and eventually the student is left with a severe visual impairment.



Retinopathy of Prematurity:

This condition is common in children who were premature babies that required high

concentrations of oxygen at birth. Scarring and detachment of the retina can result from

this condition.

Strabismus:

In this condition, both eyes are unable to gaze at an object at the same time.

Strabismus is caused by a muscle imbalance.

Cortical Visual Impairment:Cortical visual impairment is not a problem with the eye itself, but with the visual cortex

area of the brain. These children may also have other developmental delays or cerebral

palsy. Vision may change throughout the day, depending on the health, mood of the

child, or his environment.

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