This draft is out of date, there may be new research and new technologies that are relevant to this topic.
Textual content can be made easier to understand when delivered in different modes to help people with cognitive disabilities. These modes can include the addition of:
Difficulty of text comprehension by people with cognitive disabilities ranges from minimal to extreme. They may comprehend most of a web page's textual content, or none at all. These can impact people with impairments of:
People with cognitive disabilities may have to:
Issues with working memory may affect ability to multi-task so multi-modal approach needs to be used judiciously with user choice depending on the tasks in hand and the setting.
“Good cues for individuals without EMI (episodic memory impairment) can be more subtle and less central to the experience, whereas good cues for those with memory impairment need to cover the important highlights of the experience so that they can re-learn and re-construct the forgotten experience […] Individuals with EMI are more easily cognitively overloaded, which leads to a need for systems to present a smaller number of only the most powerful cues.”
People with cognitive disabilities may not:
People with cognitive disabilities:
People with cognitive disabilities may not understand text because they:
Some people with cognitive disabilities may not:
Many people with cognitive disabilities may not:
Some people with cognitive disabilities may not comprehend text because:
Other use cases include:
Text is written communication.
Textual content can be provided in a variety of alternative modes / formats as described below. Ideally, people with cognitive disabilities should be able to choose that content is delivered in the mode they comprehend best. This is an important component of the proposed Global Public Inclusive Infrastructure.
Text-to-speech (TTS) is hardware and/or software that produces human speech by a device such as a computer. Most TTS reads text aloud in a synthesized voice. Other TTS converts symbols, such as those employed by augmentative and alternative communication (AAC), into spoken speech.
Many people with cognitive disabilities, such as Dyslexia, may have the capacity to use a screen reader for TTS. However, people with severe cognitive disabilities, such as intellectual disabilities, may require simpler TTS delivery.
A common example is a TTS widget embedded in a website. An alternative is a CSS speech module, as proposed by the W3C. Advantages include that there is nothing to download and install; and learning how to use a TTS widget or a CSS speech module is dramatically simpler than learning how to use a screen reader.
The TTS should be limited to relevant content, and exclude such text as found in menus, footers, and advertisements. Another helpful feature is the visual highlighting of text as it is read aloud. Such features may help people with cognitive disabilities who are overwhelmed even by simple TTS delivery.
Video is a short film clip of moving visual images with or without audio.
To aid comprehension, video with audio should be captioned and/or have audio description, which provides important information not described or spoken in the main sound track. For example, see "Autistic spectrum, captions and audio description".
Further, video and audio should be navigable, such as:
WCAG 2.0 Success Criterion References:
An image is a picture, a representation of a visual perception.
User research has shown that text comprehension is significantly enhanced where accompanied by contextually-relevant images. A picture of an object may be easier to recognize than a textual description of it.
Diagrams and charts as visual representations could be helpful for textual descriptions of processes or flows. Employing HTML Canvas, as proposed by the W3C, diagrams and charts could be interactive and have additional descriptions for their parts to aid comprehension.
An icon is a small image or drawing that commonly represents a function. A graphic is a drawing of a visual perception or an abstract concept, or is otherwise a representation of an object or an idea.
Text accompanied by consistent iconography helps convey meaning, such as by associating discrete textual passages with each other. Similarly, a pie-chart graphic may help convey meaning easier to comprehend than a table of statistics.
What is "consistent" in this context?
A symbol is a sign that represents or suggests an idea, an object, an action, or a belief.
Symbol sets can be used for augmentative and alternative communication (AAC) to support people with cognitive disabilities who have severe speech and/or language difficulties. This can include those who may understand speech, but who are unable to express what they wish to say, perhaps because of a physical disability. (It is common for people with cognitive disabilities to also have physical disabilities.) Ideally, interoperable symbol sets could be used to replace or to augment web-based text.
Text should be written clearly and simply using the following attributes:
Plain language and clear structure will help comprehension of text-to-speech users.