Gap Analysis/non-vocal

From Cognitive Accessibility Task Force
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Communication Difficulties and Disorders may include non-vocal individuals such as those who have Aphonia, Anarthria and other disabilities that preclude any form of speech and language. The description also includes those with Aphasia who may have receptive and expressive difficulties, Dysarthria and dyspraxia where words may become unintelligible and a wide range of other difficulties that make articulation of accurate sounds difficult, language expression and understanding hard to achieve and vocalization impossible. This can include those who have hearing impairments and cognitive disabilities.

The American Association of Speech-Language-Hearing Association (ASHA) definition for communication disorders is as follows: "A communication disorder is an impairment in the ability to receive, send, process, and comprehend concepts or verbal, nonverbal and graphic symbol systems. A communication disorder may be evident in the processes of hearing, language, and/or speech. A communication disorder may range in severity from mild to profound. It may be developmental or acquired. Individuals may demonstrate one or any combination of communication disorders. A communication disorder may result in a primary disability or it may be secondary to other disabilities. - See more at:"

Cognitive functions

Cognitive function as "an intellectual process by which one becomes aware of, perceives, or comprehends ideas" (Mosby, 2009)may or may not be tied directly to a communication disorder. An individual may have high cognitive functioning and still be unable to communicate.

An example would be Aphasia that impairs an individual's abilities to speak, write, read or understand speech, or a combination of these abilities. Aphasia is caused by brain damage due to stroke, injury, brain tumors or infections and can be mild to severe.


Anarthria: Loss of the motor ability that enables speech. Complete loss of the ability to vocalize words as a result of an injury to the part of the brain that is responsible for controlling the larynx.

Aphasia: A disturbance of the comprehension and formulation of language caused by dysfunction in specific brain regions. There may be an inability to read, naming problems (finding the right word to refer to something), mis-articulated words, grammatical errors in speech, difficulty with numerical calculations, slow and effortful speech, inability to compose written language or inability to understand speech.

Apraxia: An acquired oral motor speech disorder affecting an individual's ability to translate conscious speech plans into motor plans.

Autism: A disorder of neural development characterized by impaired social interaction and verbal and non-vocal communication.

Aphonia: The inability to produce voice.

Alalia: A delay in the development or use of the mechanisms that produce speech.

Dyslalia: Difficulties in talking due to structural defects in speech organs.

Developmental verbal dyspraxia: Motor speech disorder involving impairments in the motor control of speech production.

Developmental Disabilties: Fragile X, Down syndrome, pervasive developmental disorders, fetal alcohol spectrum disorders, cerebral palsy.

Intellectual Impairment: traumatic brain injury, lead poisoning, Alzheimer's disease.

Their challenges

The following rights are summarized from the United States of America's Communication Bill of Rights put forth in 1992 by the US National Joint Committee for the Communication Needs of Persons with Severe Disabilities. (1992). Guidelines for meeting the communication needs of persons with severe disabilities. Asha, 34(Suppl. 7), 2–3.

"All people with a disability of any extent or severity have a basic right to affect, through communication, the conditions of their existence. All people have the following specific communication rights in their daily interactions.

Each person has the right to

  • request desired objects, actions, events and people
  • refuse undesired objects, actions, or events
  • express personal preferences and feelings
  • be offered choices and alternatives
  • reject offered choices
  • request and receive another person's attention and interaction
  • ask for and receive information about changes in routine and environment
  • receive intervention to improve communication skills
  • receive a response to any communication, whether or not the responder can fulfill the request
  • have access to AAC (augmentative and alternative communication) and other AT (assistive technology) services and devices at all times
  • have AAC and other AT devices that function properly at all times
  • be in environments that promote one's communication as a full partner with other people, including peers
  • be spoken to with respect and courtesy
  • be spoken to directly and not be spoken for or talked about in the third person while present
  • have clear, meaningful and culturally and linguistically appropriate communications"

How Symptoms result in Challenges for Young People who are Non-Vocal

Young non-vocal communicators are very often encouraged to make vocal speech and all efforts are made to achieve that goal. There is a persistent idea that if AAC systems are introduced early in a child’s life it will delay or prevent the development of verbal speech. This conclusion is erroneous. Research ( has shown that the introduction of AAC early in a child’s life will actually help the child develop verbal speech if that capability exists. The emphasis on making verbal speech still continues after AAC is introduced, but the fact that the child now has a means of communicating means that their right to communicate is already being supported. In situations where Speech and Language Pathologists (SLP) attempt to introduce AAC early the challenge to enlist the family/caregivers as supporters of AAC often fails. In situations where no SLP is available and/or the knowledge that there are relatively inexpensive interventions available and/or the parents/caregivers do not support the system, the child is not supported with an AAC system and expectations fall far short of the child's potential.

Major Challenges

No Support

Because very special conditions must be present to support a non-vocal communicator with AAC (resources, knowledge, support) non-vocal people are often not helped to develop even low-tech communication systems. This leads to vastly reduced opportunities for the non-vocal communicator. In individuals for whom functional level prohibits using AAC tools, there are other strategies such as indirect selection, facial expression, vocalizations, gestures, and sign languages.


Since high-tech AAC systems almost always have different operating systems and file structures, each time a new device is added someone has to manually re-program the communication system. This non-interoperability problem exists across almost all devices, even extending to multiple devices developed within by a single manufacturer. This is a major challenge facing most non-vocal people using high-tech AAC systems.

Costs of Low-Tech AAC

Communication books, symbol sets and software to customize and print icons, activity boards, picture schedules, and other low-tech communication tools are relatively inexpensive as is training for non-vocal people, SLPs, and parents/caregivers. Inexpensive is a relative term, and many communities do not have resources for even the basic tools, but if a basic methodology is employed, then even makeshift tools will enable some communication beyond making sounds, pointing, and gesturing.

Costs of High-Tech AAC

High-tech AAC systems are expensive as are extended warranties. The life of a device is usually limited to the life of the extended warranty offered by the manufacturer. This is due not only to the expense involved in supporting an out-of-warranty device but also to the fact that parts become scarce when devices are discontinued and manufacturing stops. Medicare standards (in the US?) prohibit the purchase of a new device until five years from the purchase date of the previous device so insurance companies and institutions follow that pattern. This makes the de-facto life of high-tech AAC devices five years, and this is echoed by manufacturer warranties which typically extend coverage to five years.

Costs of Lack of AAC

There are costs associated with failing to implement AAC. These costs include social and health consequences for neuro-typical as well as other communicators. AAC introduces a range of behavior modification techniques for non-neuro-typical individuals. Example: use of a picture schedule creates the opportunity for frictionless transitions in individuals for whom transitions are difficult and who may act out their fears with self-harming or other behaviors.

How Symptoms result in Challenges for People with Aphasia

Language abilities affected by Aphasia

Aphasia can affect any aspect of language -- reading, writing, speaking or listening, or combinations of these abilities. However, difficulty in reading is probably the symptom that most impacts use of the web, because most websites do not make heavy demands on the other language-related skills. Minimal writing, such as form-filling, is common on websites, but extensive writing, such as a product review or blog comment, is usually optional. Speaking is rarely required for interacting with a conventional website. It may be used in websites that support real-time human-human communication, but then a human is present who can make an extra effort to understand someone who doesn't speak fluently. Speaking, however, is often required in telephone voice applications. Using the keypad as an alternative to voice may also be difficult for some people with aphasia. Listening is required for websites where audio or video material is presented. Closed-captioning is not necessarily an option because many people with aphasia are unable to read. Many people with aphasia have some degree of hemiplegia, associated with the brain injury that affected their language. This means that using a mouse or keyboard can be difficult, so typing is not necessarily available as an alternative. In addition to difficulty reading text, some people with aphasia find certain websites confusing, for example, if there's too much material.

Variability of symptoms of aphasia

Another aspect of aphasia that impacts web accessibility is that the symptoms of aphasia vary considerably from person to person, and even in the same person from day to day. For example, some people with aphasia find that reading text for 15 or 20 minutes is ok, then the "brain shuts down". However, for some people reading is unaffected. Some people with aphasia can speak fairly well, but some don't talk at all. Specific aspects of reading might be differentially affected, for example, numbers, or people's names.

Some persona with use case that address key challenges

Persona and scenarios

Young non-vocal woman

S is a 21 year old woman with a chromosomal deletion known as Cri-du-chat Syndrome, or Five P Minus (5p-). She is a mosaic; she has the transcription error in approximately 50 percent of her cells, so some of the classic Cri-du-chat symptoms are not present such as congenital heart problems and microcephaly. S has orthopedic impairments, is ataxic (loss of full control of bodily movements) and hypotonic (abnormally low body tone) and she is developmentally disabled. She is also nearly completely non-vocal, but she has a communication system. S uses the Picture Exchange Communication System (PECS) ( as her base methodology and this is invoked in whatever communication book, picture schedule, choice boards, and other low-tech systems she uses. PECS methodology is also used in her high-tech voice output devices. Using PECS as the base methodology supports her with a consistent approach that has allowed her to develop into a very confident communicator. Since she cannot read or write she relies on icons and pictures to navigate and make her communication choices. She has been using a communication book since she was five years old (and still does) and she started using high-tech AAC systems when she was ten years old. All of her high-tech AAC devices have been purchased from a single vendor, and none of them have been interoperable, requiring her communication environment to be created manually at each change of device. None of her other non-vocal classmates/peers have communication systems.

Professional man with Aphasia

Mr C was a highly skilled accountant before he suffered a stroke, he read widely and enjoyed using technology for both his work and leisure activities. After a severe left sided brain haemorrhage he not only could not speak clearly and had difficulty understanding conversation, but he also found that he could not read or write in a recognizable way. He found it hard to concentrate and when trying to use the Internet he did not have the skills to search for things of interest let alone read the content of the web pages. He was extremely frustrated, found himself breaking down. It was extremely distressing for his family. Slowly words returned and reading skills improved but he found the clutter on the screen exasperating and often failed to select the correct link or menu item. As he progressed in his rehabilitation, he was able to read slowly and made limited use of text to speech and increased font sizing. However, he tired easily, complained of eye strain and would often give up if he could not find something he was searching for. He could not cope with CAPTCHA technology, found form filling difficult and would often buy the wrong items on Amazon by accident. However, with support and using simple technologies to de-clutter web sites, so that the text was clear without advertisements and excessive imagery Mr. C continued to take up the challenge of reading from the screen and his skills slowly improved. Eventually he was able to make use of social networks with friends who understood his difficulties and enjoyed asynchronous communication where he did not have to answer immediately and could take his time reading and composing messages.

To do: Add table of ICT Steps and challenges.

Step Challenge

How they use the web and ICT to include: Email, apps, voice systems, IM

There are many people who have spoken language communication difficulties who can cope with the use of the web and ICT at a very high level. It can provide their only method for dialogue using e-mail, instant messaging, social media etc. Individuals with cognitive disabilities as well as communication difficulties may on the other hand struggle with elements of Internet usage. They may find the intricacies of navigation, complex content and confusing messaging systems hard to access.

There remains a lack of suitable systems that are simple enough for symbol users to engage with a wide range of social networks, email and voice systems. Users generally need to use bespoke software that allows for symbol to text and text to symbol conversions. Use of the web is hampered by a lack of symbol based informational sites - simple word to symbol translation does not always solve comprehension problems.

People with aphasia use the web to shop, get information, communicate with others, and be entertained. These tasks involve the language abilities affected by aphasia (listening, speaking, reading and writing), although to different extents. Tasks like shopping, getting information and being entertained typically heavily involve reading, with some writing required for form-filling. Communicating with others via email or social networking requires both reading and writing. People with aphasia who have difficulties with spoken language may find it hard to understand the audio tracks of videos. Speaking is very rarely required for interacting with a traditional website, so speaking difficulties are unlikely to impact web usage by people with aphasia. Telephone voice applications, on the other hand, are likely to be very difficult to use for people whose speech is affected.

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

Impairments in reading ability affect many aspects of web usage. We can separate reading tasks into reading multiple paragraphs of informative text and reading captions on form items. Paragraphs of informative text can be made easier to read through general techniques that improve readability, such as simpler language, well-structured layout and organization, use of white space, and typography that enhances legibility. Form filling also requires reading, but in a different way. The purpose of reading the caption on a form is to understand what the user has to do to provide the correct information for the form. Form captions need to be simple and clear. The user should be able to hear as well as see the caption on a form as needed, even repeating the audio several times if necessary. Well-designed icons can also supplement text and audio captions. The user should also be able to hear their own input, since some people with aphasia can write but not read.

  • Important points are short with no ambiguity and may need to be highlighted with images and boxed.
  • Each point is made in a clear order so it tells a story.
  • Sentences are in first person where possible and use easy to understand words.
  • Numbers are kept in numerical format unless large and unwieldy when they also need to be in written form.
  • Increased amounts of white space and 14 point or larger sans serif fonts are used.
  • Bold type for headings and keywords
  • Colour can be used to link items
  • Pictures are of good quality and clearly represent what is being discussed.
  • Keep to one style for all items with clear logical navigation

Below is the direct quote from Tanya A. Rose, Linda E. Worrall, Louise M. Hickson, Tammy C. Hoffmann, (2012) Guiding principles for printed education materials: Design preferences of people with aphasia. International Journal of Speech-Language Pathology 14:1, pages 11-23.

  • Numbers: Present smaller numbers as figures.
  • Present larger numbers (e.g., 40,000) in both figures and words.
  • Present fractions in words.
  • People with aphasia may have a clear preference regarding which representation (i.e., figures or words) they consider easier to read, and should be provided with the option to choose, where possible.
  • Font size and typeface: Use a minimum 14-point font.
  • Use a san serif font (e.g., Verdana or Arial).
  • Use a font that is clear and bold.
  • Line spacing and blank space: Use 1.5 or double line spacing for paragraphs.
  • Ensure blank space is included around sections of text.
  • Document length: People with aphasia may want several pages of information if it is presented in a simplified format.
  • Preferences for document length may not be related to the recipient ’ s reading ability or aphasia severity, and the recipient ’ s preference for amount of information should be ascertained.
  • Graphics: Include graphics, preferably photographs.
  • Check preferences for the inclusion of graphics and preferences for graphic type, particularly when developing written information for people with more severe reading difficulties.
  • Ensure all graphics relate to the text and are labelled.

More References Kitching, J. (1990). Patient information leafl ets: The state of the art. Journal of the Royal Society of Medicine , 83 , 298 – 300. Tarleton, B.,(‎2008) Finding the Right Help - University of Bristol (accessed 27th June 2014)

Specific technologies (reference section below and how they use it differently)

Specific technologies that can help those who have communication difficulties vary enormously. They range from simple text to speech that can aid reading ability, the highlighting of text as items are read aloud, enlarged font sizing and different font styles to complex communication aids.

Those who have Aphasia may find it helpful to use the reading aids mentioned above and those who cannot communicate with text may need to use symbols or pictograms or other forms of augmentative and alternative communication (AAC). There are a wide range of systems including unaided AAC systems that do not require an technologies but may include facial expression, vocalizations, gestures, and sign languages. Then there are the low-tech communication aids which may be defined as those that do not need batteries, electricity or electronics such as communication books and boards. High-tech communication systems can include speech generating devices and software for computers, tablets, and smart phones.

Specific groups of AAC users: cerebral palsy, intellectual impairment, autism, developmental verbal dyspraxia, traumatic brain injury (TBI), aphasia, locked-in syndrome, amyotrophic lateral sclerosis, Parkinson's disease, multiple sclerosis, dementia.

Types of symbol AAC methodologies:

  • Picture Exchange Communication System (PECS),
  • MinSpeak etc
  • LAMP

Symbol sets:

  • Bliss symbols
  • Symbol Stix
  • PCS
  • Widgit
  • Sclera

Summary Existing research and guidelines

To do: Add literary summary and insert guidelines and or references

Extent to which current needs are met

   To do: Review challenges and describe where needs are met. Identify gaps

It entirely depends on the degree to which an individual is able to use language both written and spoken, expressive and receptive but it is clear that those who have considerable communication disorders with minimal literacy skills will have difficulty accessing web pages and coping with navigation within and between sites. To this extent there are considerable gaps that need to be bridged including:

  • lack of clear navigational elements - guidance should not just be about screen reader and keyboard access but also about usability
  • clutter around main content - guidance needs to ensure increased use of white space where it can be used to highlight key points
  • poor headings, paragraph structures - guidance needs to highlight how use of markers for these elements such as icons, bold text and consistent spacing can help understanding
  • poor summarising of content - guidance to authors to ensure they provide overview of content in clear fashion
  • use of colour to aid comprehension - guidance to ensure sites maintain a consistent style if this method for key points is used.
  • addition of media elements - guidance to access players and use of captions with summaries can help all users.

Potentials and possibilities

To do: Add ideas for filling gaps

"People with aphasia comprehended significantly more aphasia-friendly paragraphs than control paragraphs. They also comprehended significantly more paragraphs with each of the following single adaptations: simplified vocabulary and syntax, large print, and increased white space. Although people with aphasia tended to comprehend more paragraphs with pictures added than control paragraphs, this difference was not significant. No significant correlation between aphasia severity and the effect of aphasia-friendly formatting was found. "

Research has shown that Speech Therapists are not necessarily the best judge of whether a website is good or bad in terms of clarity, layout etc for someone who has Aphasia. (Carlye Ghidella, Stephen Murray, Melanie Smart, Kryss McKenna & Linda Worrall, (2005) Aphasia websites: An examination of their quality and communicative accessibility. Aphasiology 19:12, pages 1134-1146.)


To do: Add section

Between 6 and 8 million people in the U.S. have some form of language impairment. Research suggests that the first 6 months of life are the most crucial to a child's development of language skills. For a person to become fully competent in any language, exposure must begin as early as possible, preferably before school age. Anyone can acquire aphasia (a loss of the ability to use or understand language), but most people who have aphasia are in their middle to late years. Men and women are equally affected. It is estimated that approximately 80,000 individuals acquire aphasia each year. About 1 million persons in the U.S. currently have aphasia. Although estimating the prevalence of aphasia is difficult, especially in the developing world, aphasia is estimated to affect about 0.4 percent of the population. "This year 130,000 people in the UK will have a stroke. One-third of those who survive will have aphasia. Surprisingly, there are currently about 250,000 people with aphasia in the UK alone." - from

Voice Source: Compiled by NIDCD based on scientific publications.

Approximately 7.5 million people in the United States have trouble using their voices. Spasmodic dysphonia, a voice disorder caused by involuntary movements of one or more muscles of the larynx (voice box), can affect anyone. The first signs of this disorder are found most often in individuals between 30 and 50 years of age. More women than men appear to be affected. Laryngeal papillomatosis is a rare disease consisting of tumors that grow inside the larynx, vocal folds, or the air passages leading from the nose into the lungs. It is caused by the human papilloma virus (HPV). Between 60 and 80 percent of laryngeal papillomatosis cases occur in children, usually before the age of three. Speech Source: Compiled by NIDCD based on scientific publications.

The prevalence of speech sound disorders in young children is 8 to 9 percent. By the first grade, roughly 5 percent of children have noticeable speech disorders; the majority of these speech disorders have no known cause. By the time they are six months old, infants usually babble or produce repetitive syllables such as "ba, ba, ba" or "da, da, da." Babbling soon turns into a kind of nonsense speech jargon that often has the tone and cadence of human speech, but does not contain real words. By the end of their first year, most children have mastered the ability to say a few simple words. By 18 months of age, most children can say 8 to 10 words. By age 2, most put words together in crude sentences such as "more milk." At ages 3, 4, and 5, a child's vocabulary rapidly increases, and he or she begins to master the rules of language. It is estimated that more than 3 million Americans stutter. Stuttering can affect individuals of all ages, but occurs most frequently in young children between the ages of 2 and 6. Boys are 3 times more likely than girls to stutter. Most children, however, outgrow their stuttering, and it is estimated that fewer than 1 percent of adults stutter. Language Source: Compiled by NIDCD based on scientific publications.

References to research.

Brennan, A., Worrall, L., & McKenna, K. (2005). The relationship between specific features of aphasia-friendly written material and comprehension of written material for people with aphasia: An exploratory study. Aphasiology, 19(8), 693-711. doi:10.1080/02687030444000958

Herbert R., Haw, C., Brown, C., Gregory E. and Brumfitt, S. (2012). Accessible Information Guidelines. London: Stroke Association. Retrieved from

Caitlin Brandenburg, Linda Worrall, Amy D. Rodriguez & David Copland, (2013) Mobile computing technology and aphasia: An integrated review of accessibility and potential uses. Aphasiology 27:4, pages 444-461.

Tanya A. Rose, Linda E. Worrall, Louise M. Hickson & Tammy C. Hoffmann, (2011) Exploring the use of graphics in written health information for people with aphasia. Aphasiology 25:12, pages 1579-1599.

Aimee Dietz, Karen Hux, Miechelle L. McKelvey, David R. Beukelman & Kristy Weissling, (2009) Reading comprehension by people with chronic aphasia: A comparison of three levels of visuographic contextual support. Aphasiology 23:7-8, pages 1053-1064.

Tanya A. Rose, Linda E. Worrall, Louise M. Hickson, Tammy C. Hoffmann, (2012) Guiding principles for printed education materials: Design preferences of people with aphasia. International Journal of Speech-Language Pathology 14:1, pages 11-23.

Rose, T. A., Worrall, L. E., Hickson, L. M., & Hoffmann, T. C. (2012). Guiding principles for printed education materials: Design preferences of people with aphasia. International Journal of Speech-Language Pathology, 14(1), 11-23. doi:10.3109/17549507.2011.631583