Of all of the types of disabilities which must be considered for web accessibility, neurological and cognitive disorders are the most diverse. In general terms, these disorders involve impairment to any part of the nervous system. People with these disorders may have trouble comprehending information, viewing information, making controlled movements, as well as many other issues. Rather than trying to address all of the many disorders, for the purpose of web accessibility we will focus on the main challenges that people with cognitive and neurological disorders face when using the web.
It used to be common to see flickering, blinking, or moving content on websites as a way to draw attention to a certain element. Fortunately, this design practice has largely gone out of favor. If your website has flickering content, then you may need to reassess its need and design.
Flickering content, particularly within the range of 2 Hz and 55 Hz, can induce seizures in people with photosensitive epilepsy. You probably don’t want your website giving someone seizures, right?
Aside from the risk of seizures, flickering content is widely considered to be one of the most annoying things on a website. This is a good example of how web accessibility and good user experience are interwoven. If your website is accessible, it is also going to provide a good experience to all users – regardless of ability or disability.
If your navigation is very complex or isn’t consistent across the website, it can be very confusing for people with certain cognitive disorders. Once again this shows how web accessibility and user experience are related since having clearly, consistent navigation is considered part of good website design.
Dyslexia is the most common learning disability and, according to the group Dyslexia International (PDF), affects approximately 10% of the global population. When reading text on websites, certain styling choices can be very problematic for dyslexic individuals. For example, it is universally considered to be more difficult for dyslexics to read fonts in the Serif family. The extra lines attached to the end of the letters and numbers can cause the text to look blurry or distorted. Better choices for fonts are those in the Sans Serif family, such as Verdana.
Another common issue for dyslexic individuals is text with too much contrast. While high-contrast text is a requirement of accessible design for sight-impairments, too much contrast can make text blur on a page. Instead of using solid black text on a solid white background, for example, it is better to use a gray text. You can read the WCAG 2.0 accessibility guidelines for contrast here.
Many people with dyslexia or other disabilities may find certain fonts, colors, or contrasts easier to read. So, they may opt to override your website’s styling and use their own preferred settings. Make sure your website allows this instead of forcing users to view the website in your chosen styling.
People with certain cognitive or neurological disorders may find it difficult to read long sections of text. All text should be broken up into smaller sections with appropriate headings and significant amounts of white space between them to improve readability. Again, this is considered good website practice for all users since most users prefer to scan a page to find the information they are looking for.
The use of justified text can also be problematic for dyslexic individuals and should be avoided. Justified text is when text is aligned along the left margin and word spacing is adjusted so the text is flush with both margins.
Some neurological disorders cause jerking or make it hard to control movements. Therefore, any action on your website which requires precision – such as a dropdown menu – can be difficult for people with these disabilities. This is also problematic for people with certain physical disabilities, such as those with arthritis or quadriplegics who must use a mouth stick. Note that avoiding precision actions is also a major component of mobile web design, so improving your web accessibility for the disabled will also improve your mobile website usability.
Want to improve your website accessibility? Monsido can help!