Types of Disabilities, Part 2

In Types of Disabilities, Part 1, I learned and shared about visual, auditory, and mobility disabilities. In this post I’ll cover the rest of the list, diving deeper into the the categories covered by the Deque material and CPACC Body of Knowledge: cognitive, speech, seizure, psychological, and compound.

Cognitive

Cognitive disabilities are the most common type of disability due to its broad definitions, which include impairments in thinking, language, learning, perception, attention, memory, and problem solving.

Types of cognitive disabilities:

  • Neurodevelopmental disorders (autism, Down’s syndrome)
  • Memory impairments (Alzheimer’s, dementia)
  • Neurodegenerative disorders
  • Brain injury impairments (injury, tumors)
  • Learning disabilities (dyslexia, dysgraphia, dyscalculia, aphasia)

Causes of cognitive disabilities:

  • congenital
  • developmental
  • traumatic injury
  • infections / disease
  • chemical imbalances
  • aging

Suggested AT or strategies for improving focus, leveraging learning styles, or accommodating short-term memory:

  • screen magnifier
  • easily editable/customizable content
  • customizable fonts and colors
  • screen reader or speak aloud
  • interactive transcripts
  • blocking animations or flashing elements
  • break up long tasks by saving work and doing shorter tasks

Additional reading about cognitive disabilities:

Digital Environments
Challenge Solution
Complex designs
  • Designers can create simple, predictable, organized designs
Complex tasks
  • Simplify steps or user components
Technical problems and errors
  • Alert about errors
  • Provide clear solutions
Physical and Digital Environments
Challenge Solution
Text-based information
  • Supplement with images and visuals
  • Use simple and easy-to-understand language

Reading (dyslexia, dysgraphia)

Digital Environment
Challenge Solution
Floating words
  • Font for Dyslexia
  • Additional time to complete tasks
Letter confusion, such as p b d q
  • Font, contrast, style customization
  • Additional time to complete tasks
Timed sessions
  • Time extensions or saved work during timeouts
  • Screen reader to listen along with text or view highlighted words or phrases
  • Visible focus indicators to keep track of their position on the page
  • Applications or dictionaries that present words with pictures
  • Additional time to complete tasks
Deciphering the way content is presented
  • Custom style sheet
CAPTCHA
  • Alternate type of security feature or problem to solve
Difficulty processing visual content
  • Screen reader to listen to content
  • Additional time to complete tasks
Difficulty accurately spelling words
  • Spelling and grammar checkers

Additional Reading:

Math (dyscalculia)

People with dyscalculia have difficulty understanding or using math based on how their brain functions, as opposed to experiencing a psychologically-induced fear.

Digital Environments
Challenge Solution
Distinguishing right from left in graphic images
  • Data table or text description
  • Additional time to complete tasks
Graphs, figures and diagrams (difficult to copy)
  • Text-to-speech to listen to problems
  • Additional time to complete tasks
Calculations
  • Reference sheet with common equations, as an accommodation
  • Onscreen calculator, as an accommodation
  • Additional time to complete tasks

Speech

A person with a speech disability may have trouble articulating words or producing speech sounds. Often times people with speech disabilities will use unaided or aided Augmentative and Alternative Communication (AAC) to give them a voice. A person with a speech disability may or may not have additional disabilities. In that case, the same design considerations for blindness, low vision, motor disabilities, auditory disabilities, and cognitive disabilities may need to be used.

Causes of speech disabilities:

  • genetics
  • learning disabilities
  • auditory disabilities
  • motoric disabilities
  • autism
  • traumatic brain injury
  • stroke
  • cancer

Some types of speech disabilities include:

  • stuttering
  • cluttering
  • apraxia
  • dysarthria
  • speech sound disorder (articulation, phonetic)
  • muteness

Suggested AT or strategies for people with speech disabilities:

  • touch screens
  • alternative keyboards
  • single switch devices
  • eye-tracking technologies
  • speech-generating software
  • word prediction software
  • symbol boards and languages
  • symbol software
  • translation software
Digital Environments
Challenge Solution
Live chats / webinars / teleconferences (voice-based communication)
  • offer text-based chat
Additional disability (low vision, hard of hearing, etc.)
  • create interoperable content for optimal accessibility;
  • captions & transcripts;
  • keyboard operable;
  • multiple formats of content
Physical Environments
Challenge Solution
May have mobility issues
  • same solutions for motoric disabilities
Additional disability (low vision, hard of hearing)
  • create interoperable content for optimal accessibility
  • captions & transcripts
  • keyboard operable
  • multiple formats of content
General
Challenge Solution
producing speech sounds
  • low-tech AAC (boards, gestures);
  • high-tech AAC (computer-generated voice);
  • patience

Additional resources:

Seizure Disorders

Seizures are electrical impulses in the brain that can interfere with information processing or create involuntary muscle movement. Photo-epileptic is one type of seizure.

Causes of seizures:

  • brain injury
  • dehydration
  • sleep deprivation
  • infections
  • fevers
  • drug overdoses or withdrawals
  • flashing lights (photo-epileptic)
Digital Environment
Challenge Solution
intense flashing light, blinking, or flickering
  • eliminate or reduce speed/intensity of flashing/animation

Psychological/Psychiatric

Psychological disorders encompass a wide range of emotional and mental conditions. When the condition impacts daily life activities, it becomes a disability. Some causes of mental illness may include:

  • trauma
  • chemical imbalances
  • genetics
  • social factors

Anxiety

Anxiety disorders are the most common of psychological disorders. This disorder manifests itself as fear and worry about situations or objects. A few anxiety disorders are:

  • panic disorder
  • phobias
  • post-traumatic stress disorder (PTSD)
  • obsessive-compulsive disorder (OCD)

Mood

Mood disorders create mood fluctuations in that person. Some subcategories of mood (affective) disorders:

  • depression
  • bipolar
  • seasonal affective disorder (SAD)

Schizophrenia

Schizophrenia is broken into two groups: positive (hallucinations and delusions) and negative (lack of motivation, dreary mood, isolating). It’s theorized that this disorder is caused by either genetics, chemical imbalance, or environmental factors. Sometimes people with this disorder can struggle with:

  • expressing themselves
  • attention and memory deficits
  • controlling their movements.

It’s estimated that 2.4 million (1.1%) Americans have schizophrenia. It’s also estimated that 4.9% of people with schizophrenia commit suicide with the average age of the life lost being 28.5 years old.

Additional Resources about Schizophrenia:

Other Psychological Disorders

Attention Deficit Hyperactivity Disorder (ADHD)

ADHD is categorized as a behavioral disorder. It’s broken up into 3 subcategories: inattention, hyperactivity, and impulsivity.

Personality Disorders

Personality disorders are when people’s behavior deviate from cultural expectations. Two common personality disorders are antisocial personality disorder and borderline personality disorder.

Eating Disorders

Eating disorders cause concern over food and weight. The 3 most common eating disorders are anorexia nervosa, bulimia nervosa, and compulsive (binge) eating.

Multiple/Compound

It’s possible to have more than one disability. People with multiple disabilities may experience a combination of disabilities (of different degrees) that affect their speech, motor, visual, or hearing abilities. More inclusive accommodations help anyone with multiple disabilities to live life more independently.

In Conclusion

Without understanding the people within this multifaceted culture of disability, we can’t create solutions to the challenges they face. Read my other posts from my WAS journey that go further into keeping perspective about the people we are trying to include and serve:

Types of Disabilities, Part 1

In my experience, disabilities have been categorized in many different ways. Most commonly, I’ve seen them generalized in the following 4 categories:

  • visual
  • hearing
  • mobility
  • cognitive

In their Introduction to Web Accessibility article, WebAIM is an example of one source I’ve found these 4 categories outlined. The University of Illinois at Urbana-Champaign‘s An Introduction to Accessibility and Inclusive Design class uses the same broad categories.

In contrast, Deque’s coursework addresses disabilities with more specific categories. They propose 13 categories altogether:

  • Blindness
  • Low Vision
  • Color Blindness
  • Deafblindness
  • Auditory Disabilities
  • Motor Disabilities
  • Cognitive Disabilities
  • Dyslexia/Reading Disabilities
  • Math Disabilities
  • Speech Disabilities
  • Seizure Disorders
  • Psychological/Psychiatric Disabilities
  • Multiple/Compound Disabilities

In comparison, the CPACC Body of Knowledge breaks disability types into 9 categories:

  • Visual
  • Auditory
  • Deafblindess
  • Mobility, flexibility, & body structure
  • Cognitive
  • Speech
  • Seizures
  • Psychological/psychiatric
  • Multiple/compound

So, for the sake of staying true to the study guide, let me tackle the first 4 on the CPACC list.

Visual

Visual disabilities can refer to blindness (of varying degrees), low vision, or colorblindness. Some of these communities prefer to be acknowledged as the specific disability (blind, low vision, or colorblind) rather than visually impaired. However, it’s better to ask someone about their preferred label, rather than assuming one voice speaks for everyone.

Blindness

According to legal definition, a person is blind if they have a visual acuity of 20/200 or less with correction or who has a field of vision (what can be seen in front of the person) of 20 degrees or less in their “best” eye. In 2017 the World Health Organization (WHO) estimated 1 million people in the US and 36 million people worldwide are legally blind.

Some causes of blindness:

  • Congenital
  • Cataracts
  • Diabetes
  • Macular Degeneration
  • Glaucoma
  • Accidents or traumatic injuries to the eye
  • Stroke
  • Retinitis Pigmentosa
Digital Environments
Challenge Solution
Digital interfaces with screens
  • Screen reader
  • Interface with built-in audio or speech
  • Refreshable Braille
Inaccessible content or interface (not compatible with screen reader)
  • Designers & authors can make markup for websites and content compatible with AT.
Physical Environments
Challenge Solution
Walking independently to places
  • White cane
  • Service animal
  • GPS-based walking instructions
  • Raised tiles on the ground
  • Obstructions removed from walkways and overhangs
Signage
  • Map & geolocation apps
  • Braille labels
  • Tactile models
Consumer Products
Challenge Solution
Flat interfaces and controls
  • Tactile controls
  • Audio interface
  • Mobile app control
Text on containers or packaging
  • Braille labels
Currency
  • Mobile app to read currency
  • Redesign of currency
  • Non-cash systems of payment
Printed materials (text and images)
  • Optical character recognition software
  • Conversion to digital format
  • Conversion to Braille

Additional Reading about blindness:

Low Vision

A person is considered to have low vision if their vision is 20/70 or poorer in their best eye with correction. People with low vision often struggle to accomplish visual tasks, but with the use of assistive technologies or adaptive strategies, they sometimes can accomplish those tasks. The National Institutes of Health estimates that there are 2.9 million people in the US and 246 million worldwide with low vision.

Types of low vision:

  • blur (generalized haze)
  • blur with low contrast (generalized haze)
  • cataracts (generalized haze)
  • diabetic retinopathy (central vision)
  • glaucoma (central vision)
  • hemianopia (peripheral vision)
  • macular degeneration (central vision)
  • retinal detachment (peripheral vision)
  • aphakia (generalized haze)
  • light sensitivity
  • night blindness
Physical and Digital Environments
Challenge Solution
Small text
  • Screen magnifier
  • Software or settings to increase contrast
  • Screen reader
  • Interface with built-in speech
  • Large print
  • Digital format compatible with AT
Low contrast
  • Software or settings to increase contrast
  • Designers and content creators choose high contrast for readability

On Day 51 of my WAS certification exam journey., I posted about Users with Low Vision, which expands on some of this information.

Colorblindness

Colorblindness is the inability to distinguish between certain kinds of colors, based on brightness and luminosity. 1 in 12 men and 1 in 200 women worldwide experience colorblindness.

Types of colorblindness:

  • red-green, including red on black (Deuteranopia and Protanopia)
  • blue-yellow (Tritanopia)
  • grayscale (Achromatopsia)
Physical and Digital Environments
Challenge Solution
Color combinations with low contrast
  • Designers shouldn’t depend on color only to share information

Auditory

Auditory disabilities range from mild to profound hearing loss and deafness. Some causes of auditory disabilities:

  • genetics
  • congenital
  • premature birth
  • infections/illnesses
  • ear trauma
  • exposure to loud noises
  • aging
Digital Environments
Challenge Solution
Audio
  • Full transcript
  • Sign language interpretation
Video
  • Synchronized captions
  • Full transcript
  • Sign language interpretation
Physical and Digital Environments
Challenge Solution
Speeches or presentations
  • Sign language interpretation
  • Live captions
Physical Environments or Consumer Products
Challenge Solution
Doorbells or other alarms
  • Visual alerts
  • Tactile alerts

Deafblindess

Deafblindness is a combination of blindness and deafness. People who are deafblind encounter the same challenges as blind and deaf people would.

Digital Environments
Challenge Solution
Text or images
  • Screen reader with refreshable Braille output
Video and/or audio
  • Full transcript

Mobility, flexibility, & body structure

People with mobility impairments may experience difficulty moving, controlling, or coordinating movements of the body. Some of these disabilities subcategorized as traumatic injuries (spinal cord injury, stroke, damage to limb) or biological conditions (CP, MD, Parkinson’s, MS, ALS, RA).

Causes of mobility impairments may be due to:

  • genetics
  • premature birth
  • illnesses
  • accidents
  • aging
Digital Environments
Challenge Solution
Mouse
  • Other input devices: keyboard, alternative keyboard, mouth stick, head wand, switch device,
    speech recognition, eye tracking
  • Developers and designers ensure keyboard (and other input devices) operability
Timed sessions
  • Designers can delay timeouts
  • Designers can provide alerts for timeout
  • Designers can allow time extension
Physical Environments
Challenge Solution
Steps and escalators
  • Ramps
  • Elevators
Small spaces
  • Wider spaces for wheelchair access
  • Remove obstacles in pathways
General
Challenge Solution
Walking
  • Walker
  • Cane
  • Crutches
  • Braces
  • Wheelchair
  • Scooter
Door knobs, handles, entrances
  • Door actuators
  • Motion sensors to automate door
  • Lever handles

Additional reading about motor disabilities:

To Be Continued…

This post only covers touches on some of the categories of disabilities. Next up, I’ll be learning about cognitive, speech, seizure, psychological/psychiatric, and compound disabilities to share with you in Part 2.