Students
with disabilities meet barriers of all types. However, technology is
helping to lower many of these barriers. By using computing technology
for tasks such as reading and writing documents, communicating with
others, and searching for information on the Internet, students with
disabilities are capable of handling a wider range of activities
independently. Still, people with disabilities face a variety of
barriers to computer use. These barriers can be grouped into three
functional categories: barriers to providing computer input,
interpreting output, and reading supporting documentation. Hardware and
software tools (known as adaptive or assistive technologies) have been
developed to provide functional alternatives to these standard
operations. Specific products, and approaches to using them, are
described below.
Mobility
Impairments
Some wheelchairs may not fit under standard height computer tables and some computer users do not have enough use of their hands and arms to operate a standard keyboard or mouse.
Some wheelchairs may not fit under standard height computer tables and some computer users do not have enough use of their hands and arms to operate a standard keyboard or mouse.
Input
Equipment which provides flexibility in the positioning of monitors, keyboards, documentation, and tabletops is useful for many individuals with disabilities. Plugging all computer components into power outlet strips with accessible on/off switches makes it possible for some individuals to turn equipment on and off independently.
Equipment which provides flexibility in the positioning of monitors, keyboards, documentation, and tabletops is useful for many individuals with disabilities. Plugging all computer components into power outlet strips with accessible on/off switches makes it possible for some individuals to turn equipment on and off independently.
Some
technology assists individuals with little or no use of their hands in
using a standard keyboard. Individuals who have use of one finger, or
have access to a mouth- or head-stick or some other pointing device, can
control the computer by pressing keys with the pointing device. Software
utilities can create "sticky keys" that electronically latch
the SHIFT, CONTROL, and other keys to allow sequential keystrokes to
input commands that normally require two or more keys to be pressed
simultaneously. The key repeat function can be disabled for those who
cannot release a key quickly enough to avoid multiple selections.
Keyboard guards (solid templates with holes over each key to assist
precise selection) can be used by those with limited fine motor control.
Sometimes
repositioning the keyboard and monitor can enhance accessibility. For
example, mounting keyboards perpendicular to tables or wheelchair trays
at head-height can assist individuals with limited mobility who use
pointing devices to press keys. Other simple hardware modifications can
assist individuals with mobility impairments. For instance, disk guides
can assist with inserting and removing diskettes; a dedicated hard disk
and/or computer network access can eliminate or reduce the necessity to
do so.
For
individuals who need to operate the computer with one hand, left- and
right-handed keyboards are available. They provide more efficient key
arrangements than standard keyboards designed for two-handed users.
Some
hardware modifications completely replace the keyboard and/or mouse for
individuals who cannot operate these standard devices. Expanded
keyboards (larger keys spaced far apart) can replace standard keyboards
for those with limited fine motor control. Mini-keyboards provide access
to those who have fine motor control but lack a range of motion great
enough to use a standard keyboard. Track balls and specialized input
devices can replace mice.
For
those with more severe mobility impairments keyboard emulation is
available, including scanning and Morse code input. In each case,
special switches make use of at least one muscle over which the
individual has voluntary control (e.g., head, finger, knee, mouth). In
scanning input, lights or cursors scan letters and symbols displayed on
computer screens or external devices. To make selections, individuals
use switches activated by movement of the head, finger, foot, breath,
etc. Hundreds of switches tailor input devices to individual needs. In
Morse code input, users input Morse code by activating switches (e.g., a
sip-and-puff switch registers dot with a sip and dash with a puff).
Special adaptive hardware and software translate Morse code into a form
that computers understand so that standard software can be used.
Speech
input provides another option for individuals with disabilities. Speech
recognition systems allow users to control computers by speaking words
and letters. A particular system is "trained" to recognize
specific voices.
Special
software can further aid those with mobility impairments. Abbreviation
expansion (macro) and word prediction software can reduce input demands
for commonly used text and keyboard commands. For example, word
prediction software anticipates entire words after several keystrokes
and increases input speed.
Output
Screen output does not present a challenge, but individuals with mobility impairments who have difficulty obtaining output from printers may need assistance from others.
Screen output does not present a challenge, but individuals with mobility impairments who have difficulty obtaining output from printers may need assistance from others.
Documentation
On-screen help can provide efficient access to user guides for individuals who are unable to turn pages in books.
On-screen help can provide efficient access to user guides for individuals who are unable to turn pages in books.
For
more details on mobility impairments and computer technology, and a list
of available commercial products, visit http://www.washington.edu/doit/Brochures/Technology/wtmob.html
Blindness
Individuals who are blind cannot access visual material presented on the computer screen or in printed materials.
Individuals who are blind cannot access visual material presented on the computer screen or in printed materials.
Input
Most individuals who are blind use standard keyboards, however, Braille input devices are available. Braille key labels can assist with keyboard use.
Most individuals who are blind use standard keyboards, however, Braille input devices are available. Braille key labels can assist with keyboard use.
Output
Speech output systems can be used to read screen text to blind computer users. Special software programs (called screen readers) "read" computer screens and speech synthesizers "speak" the text. The availability of earphones for individuals using speech output systems can reduce the distractions for others nearby.
Speech output systems can be used to read screen text to blind computer users. Special software programs (called screen readers) "read" computer screens and speech synthesizers "speak" the text. The availability of earphones for individuals using speech output systems can reduce the distractions for others nearby.
Refreshable
Braille displays allow line-by-line translation of screen text into
Braille on a display area where vertical pins move into Braille
configurations as screen text is scanned. Braille displays can be read
quickly by those with advanced Braille skills, are good for detailed
editing (e.g., programming and final editing of papers), and do not
disrupt others in work areas because they are quiet. Braille printers
provide "hard copy" output for blind users.
Documentation
Scanners with optical character recognition can read printed material and store it electronically on computers, where it can be read using speech synthesis or printed using Braille translation software and Braille printers. Such systems provide independent access to journals, syllabi, and homework assignments for blind students. Some hardware and software vendors also provide Braille or ASCII versions of their documentation to support computer users who are blind.
Scanners with optical character recognition can read printed material and store it electronically on computers, where it can be read using speech synthesis or printed using Braille translation software and Braille printers. Such systems provide independent access to journals, syllabi, and homework assignments for blind students. Some hardware and software vendors also provide Braille or ASCII versions of their documentation to support computer users who are blind.
Low
Vision
For some people with visual impairments the standard size of letters on the screen or printed in documents are too small for them to read. Some people cannot distinguish one color from another.
For some people with visual impairments the standard size of letters on the screen or printed in documents are too small for them to read. Some people cannot distinguish one color from another.
Input
Most individuals who have visual impairments can use standard keyboards, but large print keytop labels are sometimes useful.
Most individuals who have visual impairments can use standard keyboards, but large print keytop labels are sometimes useful.
Output
Special equipment for individuals who are visually impaired can modify display or printer output. Computer-generated symbols, both text and graphics, can be enlarged on the monitor or printer, thereby allowing individuals with low vision to use standard word processing, spreadsheet, electronic mail, and other software applications. For individuals with some visual impairments, the ability to adjust the color of the monitor or change the foreground and background colors is also of value. For example, special software can reverse the screen from black on white to white on black for people who are light sensitive. Anti-glare screens can make screens easier to read. Voice output systems are also used by people with low vision.
Special equipment for individuals who are visually impaired can modify display or printer output. Computer-generated symbols, both text and graphics, can be enlarged on the monitor or printer, thereby allowing individuals with low vision to use standard word processing, spreadsheet, electronic mail, and other software applications. For individuals with some visual impairments, the ability to adjust the color of the monitor or change the foreground and background colors is also of value. For example, special software can reverse the screen from black on white to white on black for people who are light sensitive. Anti-glare screens can make screens easier to read. Voice output systems are also used by people with low vision.
Documentation
Scanners with optical character recognition can read printed material and store it electronically on computers, where it can be read using speech synthesis or printed in large print. Some hardware and software vendors also provide large print or ASCII versions of their documentation.
Scanners with optical character recognition can read printed material and store it electronically on computers, where it can be read using speech synthesis or printed in large print. Some hardware and software vendors also provide large print or ASCII versions of their documentation.
For
more details on visual impairments and computer technology, and a list
of available commercial products, visit http://www.washington.edu/doit/Brochures/Technology/wtsense.html
Hearing
and/or Speech Impairments
Speech and hearing disorders alone do not generally interfere with
computer use. However, advanced speech synthesizers are close enough to
human quality to act as substitute voices and thus provide a
compensatory tool for students who cannot communicate verbally. Students
with portable systems can participate in class discussions once adapted
computers provide them with intelligible speaking voices. Word
processing and educational software may also help hearing impaired
students develop writing skills.
Input
Students with hearing and/or speech impairments typically use a standard keyboard and mouse.
Students with hearing and/or speech impairments typically use a standard keyboard and mouse.
Output
Alternatives to audio output can assist the hearing-impaired computer user. For example, if the sound volume is turned to zero, a computer may flash the menu bar when audio output is normally used.
Alternatives to audio output can assist the hearing-impaired computer user. For example, if the sound volume is turned to zero, a computer may flash the menu bar when audio output is normally used.
Documentation
Individuals with hearing and/or speech impairments typically do not have difficulty using standard written or on-screen documentation.
Individuals with hearing and/or speech impairments typically do not have difficulty using standard written or on-screen documentation.
Specific
Learning Disabilities
Educational software where the computer provides multisensory experiences, interaction, positive reinforcement, individualized instruction, and repetition can be useful in skill building. Some students with learning disabilities who have difficulty processing written information can also benefit from completing writing assignments, tutorial lessons, and drill-and-practice work with the aid of computers. For example, a standard word processor can be a valuable tool for individuals with dysgraphia, an inability to produce handwriting reliably.
Educational software where the computer provides multisensory experiences, interaction, positive reinforcement, individualized instruction, and repetition can be useful in skill building. Some students with learning disabilities who have difficulty processing written information can also benefit from completing writing assignments, tutorial lessons, and drill-and-practice work with the aid of computers. For example, a standard word processor can be a valuable tool for individuals with dysgraphia, an inability to produce handwriting reliably.
Input
Quiet work areas and ear protectors may make computer input easier for individuals with learning disabilities who are hypersensitive to background noise.
Quiet work areas and ear protectors may make computer input easier for individuals with learning disabilities who are hypersensitive to background noise.
Software
that aids in efficient and accurate input can also assist. Some people
can compensate for high rates of input errors by using spell checkers,
thesauruses, and grammar checkers. In addition, word prediction programs
(software that predicts whole words from fragments) have been used
successfully by students with learning disabilities. Similarly, macro
software which expands abbreviations can reduce the necessity to
memorize keyboard commands and can ease the entry of commonly used text.
Output
Some learning disabled individuals find adaptive devices designed for those with visual impairments useful. In particular, large print displays, alternative colors on the computer screen, and voice output can compensate for some reading problems. People who have difficulty interpreting visual material can improve comprehension and the ability to identify and correct errors when words are spoken or printed in large fonts.
Some learning disabled individuals find adaptive devices designed for those with visual impairments useful. In particular, large print displays, alternative colors on the computer screen, and voice output can compensate for some reading problems. People who have difficulty interpreting visual material can improve comprehension and the ability to identify and correct errors when words are spoken or printed in large fonts.
Documentation
Some individuals with learning disabilities find it difficult to read. Computer documentation provided in electronic forms can be used by enlarged character and voice synthesis devices to make it accessible to those with reading difficulties.
Some individuals with learning disabilities find it difficult to read. Computer documentation provided in electronic forms can be used by enlarged character and voice synthesis devices to make it accessible to those with reading difficulties.
For
more details on learning disabilities and computer technology, and a
list of available commercial products, visit http://www.washington.edu/doit/Brochures/Technology/atpwld.html
Next
Steps
Continue your exploration of computer technology for students with disabilities by:
Continue your exploration of computer technology for students with disabilities by:
·
Buying the directory and/or attending the conference of Closing the Gap.
To request information, write to P.O. Box 68, Henderson, MN 56044 or
call 612-248-3294. Visit their Web site at
http://www.closingthegap.com/.
·
Contacting technology assistance centers in your state http://www.resna.org/taproject/at/statecontacts.html
or region http://www.adata.org/dbtac.html.
·
Contacting the Special Education Technology Center (Washington State
Public Schools) http://www.cwu.edu/~setc/.
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