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Adaptive Computer Access

Review Course for Assistive Technology Practitioners &

Suppliers

Learning Objective

• Recognize and refer a person needing adaptive computer access

• Categorize modifications according to input and output

• Apply technology solutions using the hierarchy of access

• Appreciate solutions useful for various categories of functional impairment

What is a computer?

• Processes instructions & manipulates data

• Stores & retrieves data• Products = letters,

numbers, words, documents, spreadsheets, graphics, etc.

• Products = images on the screen, printed document, braille, text-to-speech, music, etc.

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Why adapt computers?

• Computers are used in more than 75% of all jobs… a permanent part of everyday life!

• Supports personal meaningful and productive activity and communication at work, school, and home.

• Computers run adaptations needed to compensate for impairment simultaneouslywith the application software needed to complete the desired task or activity.

Computers compensate for…

• Upper extremity motor impairment• Paralysis, weakness, incoordination, tremor, limited

ROM found in Spinal Cord Injury, Cerebral Palsy, ALS, Cerebral Vascular Accident, Arthrogryposis, missing limbs, etc.

• Sensory impairment• Blindness, low vision, deafness, dual sensory loss

• Cognitive impairment• Learning disability, brain injury, language

impairment, mental retardation

• Combinations of the above

The HAAT Model

• Human• Activity• Assistive

Technology• Context

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The Computer “system”

• Human Technology Interface or Input– Keyboard– Mouse– Voice

• Activity Output– Monitor– Printer– Sounds

The AT or the Processor

• Central Processing Unit (CPU)

• Operating System (OS)• RAM - active memory• ROM - prewritten• Storage• Productivity Software• Modem/Network

connection

Hierarchy of Access

Use the least amount of technology necessary to do the job! For example:

1. Look at task ergonomics: seating, positioning, and mounting.

2. Use computer operating system disability access features.

3. Use “performance enhancers.”4. Use general purpose hardware or software.5. Use special or “adaptive” hardware or software.

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Begin with the Client!

• What do they want to do? Goals?• Review the referral information • Review prior assessment data

• Seating and Mobility• Fine motor control issues• Visual perception functioning• Cognitive issues• Social/Emotional issues

• Need more data?

Goals

• Educational• Vocational• Leisure• Information Gathering• Communication

Review Prior Assessment Data

• Prior experience with computers and special access technology

• Comfort with technology• Education level• Personal goals• Interests• Motivation• Proposed activity environment• Support systems• Availability of technical support• Funding sources

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How do you know what adaptations to consider?

• The typical keyboard requires:• Strength, • Endurance, • Reach (range of motion) & motor

accuracy, • Isolated motor movement (one key

at a time),• Sequenced motor movements which

over time becomes easy and efficient.

How do you know what adaptations to consider?

• The typical mouse requires:• Understanding the mouse is how you

choose,• Perceptual motor skill to move hand in

one plane & get feedback in another plane,

• Locate/see the mouse and track it as it moves across a busy background,

• Move the pointer/cursor to a precise point,

• Click, double click, drag (click and move),

• Movement patterns eventually become easy and efficient.

How do you know what adaptations to consider?

• The typical monitor requires• Visual acuity that is functional or

correctable, • Ability for eyes to work together, • Ability to track, • Perception: figure ground, form

constancy, etc.• Ability to read or literacy, • Usually sits on a desk but alternative

placement is possible.

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How do you know what adaptations to consider?

• Figure out how to fill in the gap between “typical”and where the client is currently…

– Is it the individual’s performance deficits? • (e.g., poorly controlled motor movements, low vision).

– Is it the ergonomic requirements of computing? • (e.g., can’t reach the whole keyboard, low endurance).

– Is it interference from the performance context? • (e.g., distractibility when doing written assignments).

Seating, Positioning

and Mounting• Work as a team• If client uses a wheelchair or

has mobility limitations consider a height adjustable table.

• Work surface height can easily vary for – Task– Changing user need– Time of day

Seating, Positioning and Mounting

• Get hands into optimal or “neutral” position to reduce strain or enhance function– Consider low cost wrist

rests – Use tilt adjustment on

keyboard– Try an under-the-desk

keyboard tray

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Control Enhancers

• Mobile forearm supports

• Mouth sticks• Typing sticks• Head pointers• Easels and copy

holders

Control Enhancers

Built-in Accessibility Features• Both Windows and Apple have operating system

level features to compensate for impairment:– One-handed keyboarders, mouthstick or typing stick

users.– Keyboarders with poor coordination (e.g., too long on the

key, difficulty with overshoot, inability to precisely point with the mouse).

– Hearing impairment– Low Vision– Cognitive impairment

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Accessibility Options

• Go to “Control Panel”• Choose “Accessibility

Options”• Choose and set up the

desired features• Learn more at :

– http://www.microsoft.com/enable– http://www.apple.com/accessibility

Change the keyboard layout

• QWERTY versus Dvorak• Half QWERTY

Adaptations for Physical Impairments

• Limited Range of Motion

Magic WandTASH Mini BAT Keyboard

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Adaptations for Physical Impairments

• Incoordination

Keyguards Intellikeys

Adaptations for Physical Impairments

• Inability to move hands

HeadMaster Jouse

Adaptations for Physical Impairments

Onscreen keyboards: WiVik

• For use with alternate mouse control

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Adaptations for Physical Impairments

• Loss of hand and head movement

EyeTech Tongue Touch Keypad

Direct Selection

• All of the adaptations discussed up to this point use or improve direct selection.

• Definition: ALL items in the selection set are available ALL the time.

• The user simply chooses the desired item.• Cognitively simpler, physically more complex.• Example: a keyboard

Indirect Selection• Definition: NOT ALL items

in the selection set are available ANY time.

• The user must WAIT until the desired option is offered, then choose with a switch.

• Physically simpler, Cognitively more complex.

• Use when physical disability is severe.

• Examples: alphabet array

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Before choosing scanning…

• Determine that direct selection is NOTpossible.

• Carefully select a switch based on physical assessment of body sites capable of reliable, effortless, movement.

• Match the type of switch to the part of the body that will activate it.

• Optimize the selection set to support greatest efficiency.

• Choose from the variety of single switches

Rocker SwitchPneumatic: Sip n’ Puff

Small Switches

Types of Switches

Indirect selection - scanning

• Text generation at 3-4 wpm.

• Pair with rate enhancement strategy.

An alphanumeric scanning array

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Rate Enhancement

• Arrange items in array so frequently used choices are offered sooner.

• Pros: reduces number of keystrokes or switch activations to increase efficiency.

• Cons: creates additional cognitive effort and increased sensory load.

• Three types of rate enhancement: – word prediction– abbreviation expansion– encoding schemes, e.g., Minspeak™

Word Prediction• Completes word.• Uses rules of

grammar, recency and frequency to anticipate the next word.

• Automatic capitalization after terminal punctuation.

Abbreviation Expansion

• User creates and saves the abbreviation.• User enters the abbreviation.• Computer replaces the short string of letters

with a complete sentence, several sentences or paragraphs.

• Useful for frequently entered data.• Usually used in combination with word

prediction.• N&A = Joanne Jones

5044 Forbes TowerUniversity of PittsburghPittsburgh, PA 15260

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Single switch use doesn’t always mean scanning!

• Another option with a single switch is Morse code – Another form of indirect selection– Use a single switch sends code for a letter, number or

command.– Frequent letters = shortest codes– “Dah” is 3 times longer than “Dit”– Advantages: speed (30 wpm), minimal motor control,

becomes automatic– Use 1 or 2 switches: which ever is less fatiguing!– Needs alphanumeric + other computer-required

characters. – No uniformity between applications: E-Z Morse

Single switch use doesn’t always mean scanning!

• Another option with a single switch is control of Single Switch Software – This only allows control of specific software applications– The switch often emulates a mouse click, space bar or

return– Requires a switch interface

Voice Recognition

Naturally Speaking

Via Voice

• Greatly improved in recent years.

• Uses continuous speech not discrete speech.

• Cost = Low to Moderate.

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Voice Recognition:Disadvantages• Recognition rate declines as voice

fatigues.• Not suitable in all environments e.g.,

public library, noisy factory floor.• Requires newer, high performance

computer.• High learning curve and cognitive load.• Ability to think of voice as an input tool.• Difficult with learning disability• Occasional keyboard entry and mousing

may still be needed.

Adaptations for Visual Impairments

• Adapt the monitor’s output– Resolution or contrast – Magnifiers

• ZoomText, CloseView, enLARGE, Magic, etc.

• Substitute for the monitor’s output.– Text-to-speech– Refreshable Braille

• Printer’s output– Large print or Braille

Serif Font

San Serif Font

Adaptations for Auditory Impairments

• Modify the sound output that accompanies warnings or alerts– Flash screen or title bar– Multiple signals types– Go to accessibility options in the computer operating

system

• Keep auditory impairment in mind with movie clips or voice-overs on multi media materials.

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Adaptations for Cognitive Impairment

• Learning Disability, brain injury, etc.• Specific learning disability requirements:

– Reading– Writing– Combinations– Organization and sequencing

Adaptations for Cognitive Impairment

• Scan print and convert to computer text• Text-to-speech• Text highlighting • Modify text spacing and formatting• Vocabulary support• Voice notes• Daily schedule software

Additional Resources

• Alliance for Technology Access – http://www.ataccess.org/

• Microsoft – http://www.microsoft.com/enable/

• Apple – http://www.apple.com/accessibility/

• RESNA-SIG11 Computer Applications – http://www.RESNA.org

• Koester, H.H. & Levine, S.P. (1996). Effect of a word predictionfeature on user performance. AAC: Alternative and Augmentative Communication. (12)155-168.