HCI Education

Cognitive Disability and the Web

Dr Steve Green
Dr Elaine Pearson

Special Needs Computing Research Unit
University of Teesside

E-mail: s.j.green@tees.ac.uk


A number of groups (most notably W3C, DISinHE and many who are mindful of the changes in the Disability Discrimination Act) are promoting the world wide web for people with disabilities. This is not surprising as the potential benefits of the web as an unlimited source of information is huge. The problems associated with web sources are also equally well understood. In particular the anarchic nature of the Internet means that almost anyone can publish to the web and much of that material is either of dubious quality or difficult to find. This problem is exacerbated for people with disabilities when coupled with the more obvious problems of reduced accessibility. Sensory deficit, including visual impairment, imposes some very real problems because of the essentially multimedia nature of many modern sites. Nevertheless much of the current material on the web is essentially text-based and therefore accessible to speech-based browsers. Special tools (e.g. WebBobby) can also check the site for compatibility with such browsers. An area, however, that has received very little consideration to date is the use of the web with people with cognitive disabilities and special educational needs (SEN).

The Problem

Currently the most well researched area of cognitive disability is a form of specific learning difficulties (SLD) more commonly referred to as dyslexia. Even here the types of problems encountered are various affecting visual perceptions or acuity, memory or mental processing. At a simple level some fonts and background-foreground colour combinations are particularly difficult to read for many people with dyslexia. Black characters on a white background using 10 point Times New Roman would be one example of a common combination which is likely to cause difficulties. Other confusions can occur because of inconsistent or poorly considered divisions of the screen into panel and button areas or simply by separating related information into different screen windows or at the two ends of a scrolling text window.

In many other areas of cognitive deficit (e.g. for people with mental handicap, Down's syndrome, autism etc.) the problems might appear at first glance to be very obviously one of mental immaturity affecting reading ability and cognitive awareness. However a closer examination shows that many cognitive disabilities are not just a matter of immature mental development but once again one of specific learning difficulties (SLD). For example there are a sizeable minority of people with Asperger's syndrome (a form of autism) who can show remarkable areas of skill coupled with glaring areas of cognitive disability. Some of these people, with special help, can continue on to college or university. Most people with moderate or severe cognitive disabilities may not attend college but will often attend an adult training centre or community centre and like the rest of us are clear targets for lifelong learning. We do them a disservice if all we ever present is material appropriate to their reading age without considering their social maturity, interests or self-esteem. After all we would not expect adult literacy classes to revert to Janet and John and this principle applies equally well to the presentation or selection of appropriate web materials.

The Solution?

We have presented the problem in a very simplistic way. Clearly a more thorough treatment of the potential areas of cognitive deficit is required if we are to make serious inroads into the problems of web design for all. While we cannot expect every web author to be an expert in anything much other than (hopefully) the subject matter of the site itself, we might propose that authors ask themselves three questions:

  1. Who is my site aimed at?
  2. What are the consequences of the design I propose for my audience?
  3. Are there any checks I can carry out?

If the answer to the first question is “everyone!” then we will reply “do you really mean to all with any type of physical, sensory, perceptual or cognitive disability, the old, the young, those whose first language is not English or who come from another cultural background?” Obviously not all sites are expected to be suitable for everyone and only a very few could reasonably or economically be made available to even the majority but we should be clear about who we are excluding. Our general principle is that we should aim not to exclude anyone unnecessarily.

Secondly we should be aware of the problems our design will cause different members of our audience. This presupposes that the author actually has a web design. Assuming they do we can then proceed to consider what media elements we will use:

  • If images or video then alternate descriptions are needed for the visually impaired
  • If sound then subtitles, text or signs for the deaf
  • If text then glossaries or appropriately differentiated pages for the poorer readers.

Differentiation is the key to supporting those with cognitive disabilities. It can take the form of simpler text, pictures and voice-overs to make the reading and interaction tasks more manageable, better structured or supported. These elements relate not only to the site content itself but equally to its navigational and interaction features.

In answer to the third question, the best check is a good initial design. Automated checking tools could feasibly tell us how suitable the site is for the visually impaired, the deaf, dyslexics and various specific cognitive or learning deficits. We can classify the reading age and assess the level of differentiated support. However these are remedial tools and no substitute for good design up-front. This is not to say that we need to work with the lowest common denominator. Clearly we should not avoid the use of visual or multimedia elements because some people have sensory impairments any more than we avoid using text because some people are poor readers. What we really need are a set of good design principles which take account of these factors.


The basic principles that we should follow are those of inclusion and differentiation. We should make our web-sites as open as possible by thinking about and catering for the needs of different users. We should be aware of who we include and exclude as a result of our design.

But at the end of the day why should we take the trouble? Some would say it is because of the changes in the law. Others that “it is our moral duty to think of those less fortunate than ourselves”. This is not our argument. If there is a professional obligation it is to think of every individual in our potential audience. However a much more pressing argument is that the Internet is an open communication channel to the world. Why should we reasonably choose to exclude anyone who can benefit from this universal medium?