This Wiki page is edited by participants of the Cognitive and Learning Disabilities Accessibility Task Force. It does not necessarily represent consensus and it may have incorrect information or information that is not supported by other Task Force participants, WAI, or W3C. It may also have some very useful information.
- 1 Note: This page is out of date. This page has been ported to the github version. If you have edits for this page please send them to the list or to Michael and Lisa.
- 2 NOTE
- 3 Description
- 4 Cognitive functions
- 5 Symptoms
- 6 Their challenges
- 7 Some persona with use case that address key challenges
- 8 How they use the web and ICT to include: Email, apps, voice systems, IM
- 9 How people with cognitive disabilities use optimized content and special pages
- 10 Characteristics of content optimized for this group
- 11 Specific technologies (reference section bellow and how they use it differently)
- 12 Summary Existing research and guidelines
- 13 Extent to which current needs are met
- 14 Potentials and possibilities
- 15 Prevalence
- 16 References to research.
Note: This page is out of date. This page has been ported to the github version. If you have edits for this page please send them to the list or to Michael and Lisa.
We are using this wiki page (and sub pages) as a white board for building a document and collecting notes. Information on this page should NOT be quoted.
Down syndrome also known as Trisomy 21, is a genetic disorder caused by the presence of all or part of a third copy of chromosome 21. It is typically associated with physical growth delays, characteristic facial features and mild to moderate intellectual disability.
Education and proper care has been shown to improve quality of life. Some children with Down syndrome are educated in typical school classes while others require more specialized education. Some individuals with Down syndrome graduate from high school and a few attend post-secondary education.
Down syndrome is best known for its affect on the development of literacy and language related skills. Down syndrome is widely recognized as being a specific learning disability of neurological origin that does not imply low intelligence or poor educational potential, and which is independent of race and social background.
This section is a technical reference. Jump to the next section on Symptoms for more practical information.
Improvements in medical interventions for people with Down's syndrome have led to a substantial increase in their longevity. Diagnosis and treatment of neurological complications are important in maintaining optimal cognitive functioning.
The cognitive phenotype in Down's syndrome is characterized by impairments in morphosyntax, verbal short-term memory, and explicit long-term memory. However, visuospatial short-term memory, associative learning, and implicit long-term memory functions are preserved. Seizures are associated with cognitive decline and seem to cause additional decline in cognitive functioning, particularly in people with Down's syndrome and comorbid disorders such as autism. Vision and hearing disorders as well as hypothyroidism can negatively impact cognitive functioning in people with Down's syndrome.
Dementia that resembles Alzheimer's disease is common in adults with Down's syndrome. Early-onset dementia in adults with Down's syndrome does not seem to be associated with atherosclerotic complications.
Source: The Lancet
People with Down syndrome often struggle with short-term auditory memory. Most people use memory to process, hold, understand and assimilate spoken language. Auditory memory relates directly to the speed with which we can articulate words, and influences the speed at which people learn new words and learn to read.
Theories about memory suggest that words we hear are received and stored in our working memory in order to make sense of them. They are then transferred to a more long-term store. However, words are only retained in the working memory for two seconds unless consciously kept there by silently repeating them to oneself, called rehearsing. The amount of information we can retain within the two-second span is called the auditory digit span.
Is there a relationship between Down’s syndrome and working memory?
Yes, many people with Down’s syndrome have difficulties in this area. Generally, long-term memory is not impaired; neither is the visual memory, which is often far stronger.
Source: Sandy Alton
Visual Recognition Skills
The cognitive profile observed in Down syndrome is typically uneven with stronger visual than verbal skills, receptive vocabulary stronger than expressive language and grammatical skills, and often strengths in reading abilities. There is considerable variation across the population of people with Down syndrome.
Many studies have included typically developing children matched for chronological age, for non-verbal mental age or on a measure of language or reading ability. Individuals with Down syndrome have also been compared to individuals with learning difficulties of an unknown origin and to individuals who have learning difficulties of a different aetiology (e.g., specific language impairment).
The particular measures of language, reading or non-verbal ability used for matching can affect the conclusion drawn. There are also behavioral aspects of the Down syndrome phenotype other than non-verbal ability and language ability (such as motivational style) that may affect their performance on tasks, including attainment tests, and need to be taken into account.
In terms of education, there is strong evidence to suggest that the relatively recent policy of educating children with Down syndrome in mainstream schools has had a positive effect on language skills and academic attainments. This means that the findings of studies conducted a number of years ago need to be interpreted with caution.
Source: Margaret Snowling, Hannah Nash and Lisa Henderson
Intellectual and cognitive impairment and problems with thinking and learning and usually ranges from mild to moderate. Common symptoms are:
- Short attention span
- Poor judgment
- Impulsive behavior
- Slow learning
- Delayed language and speech development
- Reading is typically slow and laborious. If they are undiagnosed or diagnosed late, they may be illiterate or barely literate.
- Concentration tends to fluctuate.
- Poor and unusual spelling and grammar.
- Handwriting is unusable or very messy.
- Poor physical coordination
- Difficulty remembering information (tends to fluctuate)
- Difficulty with organizing and planning
- Difficulty working within time limits
- Difficulty thinking and working in sequences, which can make planning difficult
- Visual processing difficulties, which can affect reading and recognizing places
- Poor auditory processing skills
- Listening to oral instructions difficult, tiring and confusing
Down syndrome symptoms vary with each person and appear at different times in their lives.
- Poor short term memory for facts, events, times, dates, symbols.
- Poor working memory; i.e. difficulty holding on to several pieces of information at the same time. This is especially challenging while undertaking a task e.g. taking notes as you listen, addressing compound questions.
- Mistakes with routine information e.g. giving your age, and phone number or the ages of children.
- Inability to hold on to information without referring to notes.
Down syndrome do not tend to automatise skills very well, and a high degree of mental effort is required to carrying out tasks that other individuals generally do not feel requires effort. This is particularly true when the skill is composed of several subskills (e.g. reading and writing).
- Difficulties with taking in information efficiently (this could be written or auditory).
- Slow speed of information processing, such as a 'penny dropping' delay between hearing or reading something and understanding and responding to it.
- Lack of verbal fluency and lack of precision in speech. (relevant for voice systems)
- Word-finding problems.
- Inability to work out what to say quickly enough.
- Misunderstandings or misinterpretations during oral exchanges.
- Sometimes mispronunciations or a speech impediment may be evident.
- Difficulty in acquiring reading and writing skills. Reading is likely to be slow.
- If they are undiagnosed or diagnosed late, may be illiterate, barely literate and it will be very laborious
- Where literacy has been mastered, problems continue such as pore spelling, difficulty extracting the meaning from written material, difficulty with unfamiliar words, and difficulty with scanning or skimming text.
- Particular difficulty with unfamiliar or new language such as jargon.
- Difficulty organizing a sequence of events.
- Incorrect sequencing of strings of number and letter. (passwords, phone numbers)
- Chronic disorganisation and misplacing/losing items.
- Difficulty with time management and passage of time
- Difficulty with finding the way to places or navigating - even in the context of building. Often get lost.
- Sensitivity to noise and visual stimuli.
- Impaired ability to screen out background noise / movement.
- Sensations of mental overload
- Tendency to "switch off".
Lack of awareness
- Failure to notice body language.
- Failure to realize the consequences of their speech or actions.
- Some people with Down syndrome difficulties may experience visual stress when reading. Especially when dealing with large amounts of text. So brakes are often needed
It must be emphasized that individuals vary greatly in their Specific Learning Difficulties profile. Key variables are the severity of the difficulties and the ability of the individual to identify and understand their difficulties and successfully develop and implement coping strategies.
By adulthood, many people with Specific Learning Difficulties are able to compensate through technology, reliance on others and an array of self-help mechanisms - the operation of which require sustained effort and energy. Unfortunately, these strategies are prone to break down under stressful conditions which impinge on areas of weakness.
Effects of stress
People are particularly susceptible to stress (compared with the ordinary population) with the result that increase their impairments.
Some persona with use case that address key challenges
Scenario A is a high school student with Down syndrome.
Although she can read at a 3rd grade level it is slow and she finds it difficult. Books geared towards a younger audience with a lot of pictures help. Plus she can comprehend and remember stories read by others. Test taking is very stressful and it helps when the teacher can help her take the test orally. She is strong on the computer especially when interested in the topics. She can surf the internet and do research but needs to be reminded to stay on task and not get distracted by other sites and advertisements. She does not use assistive technology but has in the past to improve her reading skills. The teacher aide has to remind her to stay on task during exercise. She can do simple research projects but only if supported with reminders and visual ques.
|Doing a short review of different option and finding the most appropriate|
|Finding the right content in the right document|
|Read the right content|
|Collecting the information|
|Coping for Citing the resources and collecting them with the right information|
|Remembering the process (re-finding it next time)|
|Saving the work|
|Putting it together and writing the paper||Her writing is poor and so this would be Out of scope of this user case|
How they use the web and ICT to include: Email, apps, voice systems, IM
To do: Add table.
How people with cognitive disabilities use optimized content and special pages
To do: Add examples with descriptions of features
Characteristics of content optimized for this group
To do: Add descriptions of key features and how it helps users overcome challenges
Specific technologies (reference section bellow and how they use it differently)
To do: Add section
Summary Existing research and guidelines
Aim to ensure that written material takes into account the visual stress experienced by some Down syndrome people, and to facilitate ease of reading. Adopting best practice for Down syndrome readers has the advantage of making documents easier on the eye for everyone. Font. (Remember people with Down syndrome can be easily distracted and confused)
- Use a plain, evenly spaced sans serif font such as Arial and Comic Sans. Alternatives include Verdana, Tahoma, Century Gothic, Trebuchet.
- Font size should be 12-14 point. Some dyslexic readers may request a larger font.
- Use dark colored text on a light (not white) background.
Headings and Emphasis
- Avoid underlining and italics: these tend to make the text appear to run together. Use bold instead.
- AVOID TEXT IN BLOCK CAPITALS: this is much harder to read.
- For Headings, use larger font size in bold, lower case.
- Boxes and borders can be used for effective emphasis.
- Use left-justified with ragged right edge.
- Avoid narrow columns (as used in newspapers).
- Lines should not be too long: 60 to70 characters.
- Avoid cramping material and using long, dense paragraphs: space it out.
- Line spacing of 1.5 is preferable.
- Avoid starting a sentence at the end of a line.
- Use bullet points and numbering rather than continuous prose.
- Use short, simple sentences in a direct style.
- Give instructions clearly. Avoid long sentences of explanation.
- Use active rather than passive voice.
- Avoid double negatives.
- Be concise.
- Flow charts are ideal for explaining procedures.
- Pictograms and graphics help to locate information.
- Lists of 'do's and 'don'ts' are more useful than continuous text to highlight aspects of good practice.
- Avoid abbreviations if possible or provide a glossary of abbreviations and jargon.
- For long documents include a contents page at the beginning and an index at end.
Note: Checking Readability. To set your spell checker in Word 2003 to automatically check readability, go to Tools, Options, Spelling, and Grammar, then tick the Readability request. Word will then show your readability score every time you spell check. In Word 2007 Click the Microsoft Office Button, and then click Word Options. Click Proofing. Make sure Check grammar with spelling is selected. Under When correcting grammar in Word, select the Show readability statistics check box. Check long documents in sections, so that you know which parts are too hard.
- RNIB Web Access Centre: http://www.rnib.org.uk/professionals/webaccessibility/Pages/web_accessibility.aspx.
- BBC: My web, my way. Making the web easier to use: http://www.bbc.co.uk/accessibility/guides/allguides_index.shtml
Extent to which current needs are met
To do: Review challenges and describe where needs are met. Identify gaps
Potentials and possibilities
To do: Add ideas for filling gaps
The estimated incidence of Down syndrome is between 1 in 1,000 to 1 in 1,100 live births worldwide. Each year approximately 3,000 to 5,000 children are born with this chromosome disorder and it is believed there are about 250,000 families in the United States of America who are affected by Down syndrome.
Sixty to 80 percent of children with Down syndrome have hearing deficits. Forty to 45 percent of children with Down syndrome have congenital heart disease. Intestinal abnormalities also occur at a higher frequency in children with Down syndrome.
Children with Down syndrome often have more eye problems than other children who do not have this chromosome disorder. Another concern relates to nutritional aspects. Some children with Down syndrome, in particular those with severe heart disease often fail to thrive in infancy. On the other hand, obesity is often noted during adolescence and early adulthood. These conditions can be prevented by providing appropriate nutritional counseling and anticipatory dietary guidance.
Thyroid dysfunctions are more common in children with Down syndrome than in other children. Skeletal problems have also been noted at a higher frequency in children with Down syndrome. Other important medical aspects in Down syndrome, including immunologic concerns, leukemia, Alzheimer disease, seizure disorders, sleep apnoea and skin disorders, may require the attention of specialists in their respective fields.
Source: World Health Organization - http://www.who.int/genomics/public/geneticdiseases/en/index1.html
References to research.
To do: Add section