Children with visual impairments

Students with visual impairments are one of the smallest groups of students being served by special educational services in the public schools. However, they are increas­ingly being served in public schools rather than special schools. Their numbers in public schools increased from about 10 percent to almost 90 percent between 1950 and 1990.

The definitions of legal blindness and low vision are based on measures of visual acuity and field of vision. Low vision is defined as acuity from 20/70 to 20/180 in the best eye after correction and a field vision from 20 to 180 degrees. Legal blindness is defined as 20/200 acuity or less in the best eye after correction and/or a field of vision restricted to an area of 20 degrees or less (tunnel vision).

These definitions are useful for assessment of needs for special services. They do not specify actual vision. One must consider the amount of vision in the worst eye, the perception of light, the actual field of vision (if it is between 20 and 180 degrees), and visual efficiency and functional vision. These last two terms are used to de­scribe how well a person uses whatever vision is avail­able.

Visual impairments may be separated into the catego­ries of blind or low vision based on visual efficiency and functional vision. A child with so little functional vision that he or she learns primarily through the other senses is assessed as blind. A child with enough functional vision to learn primarily through the visual channel is assessed as having low vision. About 80 percent of the visually im­paired students who attend public schools are assessed as having low vision rather than blindness. Children with refractive errors (nearsightedness, farsightedness, and astigmatism) are rarely assessed as low vision students in need of special services. This is because refractive errors can usually be corrected with glasses.

The causes of legal blindness and low vision are not always easy to determine. About 15 percent of blindness is due to unknown factors. Heredity and prenatal factors (maternal illness, drugs, prematurity, low birth weight) are believed to contribute to more than one-half of all visual impairments. Other known causes of blindness or low vision are diseases, injuries, poisonings, and tumors.

Depending on the nature and the degree of the visual impairment, a teacher may need to become acquainted with a wide variety of special services used to assist in appropriate education for blind or low vision students.

Most children who are blind are taught to read using their sense of touch. Braille is a form of writing using raised dots that are "read" with the fingers. It takes many years to learn to read braille. Most braille readers read considerably slower than print readers. Their individu­alized education programs (lEPs) may include braille books and braille reading, and writing braille with a slate and stylus or brailler (six-keyed device like a typewriter). Most children who are blind also use Optacon scanners, talking books (books on tape), speech plus talking hand­held calculators, closed-circuit television, typewriters, and/or personal computers with special software. lEPs are specifically designed and annually updated to meet the unique and changing needs of each child who is blind.

Most children with low vision are taught to read using their residual vision. Their lEPs usually include the goals of using low vision aids and large type to read print. They also may use felt tip pens, wide-lined paper, or typewriters for writing, and personal computers with special software for both reading and writing.

Children who are blind or have low vision need to learn to use their other senses to provide information they miss through their eyes. Listening skills are especially impor­tant. Blind children are not born with better hearing. Their hearing may be normal, below normal, or they may be hearing impaired or deaf. If they have any hearing ability they need to learn to use it as efficiently as possible. lEPs usually include the goal of teaching discrimination of near-far, loud-soft, high-low, and of ignoring distracting back­ground noises.

Children who are blind or have low vision usually have more difficulty with orientation of their bodies in space and movement in their spatial environments than normal vision children. Most teachers need to include lessons in orientation and mobility (O&M) to the lEPs of visually-impaired students. These lessons are usually given by trained O&M instructors in conjunction with regular edu­cation teachers. The long cane used in O&M both serves as a probe and bumper for its user, and also signals sighted persons that its user is visually impaired. Only a very small percentage of visually-impaired students use guide dogs. If a student has a guide dog, the teacher and sighted student must learn to treat the dog as a working guide, not as a pet. Most persons with visual impairments occasionally use sighted persons as guides. Teachers and sighted students need to learn how to guide their blind or low vision friends with a few simple dos and don'ts.

Each child with low vision needs to feel accepted by his or her more visually abled peers. The teacher plays a major role in encouraging positive interactions between children with and without visual impairments. The teacher should discuss each child's special visual needs with the class. Having one's very own personal computer, televi­sion, talking calculator, or other intriguing piece of techno logical equipment may be viewed as favoritism. The need for the equipment should be explained fully at the begin­ning of the school year and whenever questioned during the remainder of the school year. With each new school year, and with each technological change, more explana­tions are required to help children without visual impair­ments understand the special child's needs.

The first article selected for this unit examines the efficacy of classroom special services for low vision stu­dents. In most classrooms, the use of technological equip­ment lags behind the students' needs. The next article suggests an efficient way for public schools with blind or low vision students in regular classrooms to utilize the services of schools for the blind. Residential schools can provide a wide range of services to mainstreamed chil­dren on an intermittent basis. The last article in this unit addresses the education of children who have hearing impairments in addition to visual impairments. Children who are deaf-blind have many special needs. This selec­tion is concerned with teaching students who are deaf-blind to make choices and develop independence.

Looking Ahead: Challenge Questions

How many low vision students who qualify for special educational services are actually receiving them, accord­ing to the article "Efficacy of Low Vision Services for Visually Impaired Children"?

Is it possible for public schools and residential schools for the blind to collaborate? Can children in inclusive education programs be pulled out to residential schools for occasional hands-on instruction?

How can choice making be taught to students who are deaf-blind?

Дата добавления: 2015-07-11