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James Jackson

Usability/Accessibility Research and ConsultingMichigan State University

Towards Universally Accessible Typography: A Review of

Research on Dyslexia

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Why Typography?

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How Type is Set Affects Readability

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Why Typography and Dyslexia?

• Anecdotal evidence– Many people with dyslexia find ways to use technology to

manipulate type, e.g. reading on a tablet– Many people with dyslexia find some fonts more readable

than others• British Dyslexia Association Style Guide

– Basis for common accommodations especially in primary school

• Significant amount of new research

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Dyslexia and Visual Processing

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Myths(i.e. this isn’t what most dyslexic users see)

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Reality

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Dyslexia and Lateral Masking

• Lateral masking makes it more difficult to distinguish individuals letters when they are close together

• In general people experience more lateral masking in peripheral vision than in central vision– But individuals with dyslexia experience it less in

peripheral vision than individuals without dyslexia• Lateral masking may affect how particular aspects of

typography affect the readability of text for individuals with dyslexia

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Universal Design

• Largely because of technological limitations, the basic rules of typography have been determined by meeting only the minimal needs of the average reader

• Improving typography for individuals with dyslexia can improve it for everyone– Because readability affects everyone, and the visual

distortions that do affect dyslexia affect everybody

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Letter Spacing

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Letter Spacing

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Letter Spacing

• Zorzi, et al. (2012)– Increased letter spacing improved readability for young

students with dyslexia• Perea, Panadero, Moret-Tatay, & Gómez (2012)

– Slightly increased letter spacing improved word identification for all readers, but especially for young readers and read readers with dyslexia

• Schneps, Thomson, Sonnert, Pomplun, Chen, & Heffner-Wong (2013)– Increased letter spacing allowed struggling readers to

catch up with dyslexic readers who had spent considerable time and energy developing their literacy skills

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Line Length

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Line Length

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Line Length

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Line Length

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Line Length

• Extremely short line length makes it easier to return to the left margin when starting a new line, improving readability (Schneps Et. Al., 2013)

• This effect may be true for non-dyslexic readers as well

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Design Challenges and Recommendations

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Challenges

• Most studies are with children• Dyslexia and literacy skills are both developmental

– Developing readers may need different type than compensated dyslexics

• It’s hard to study ranges and how different typographic features interrelate

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Recommendations – Reading Apps/Devices

• Make sure users have some control of how text is presented– Particularly Font Size and Line Length– Appropriate ways to provide control over letter spacing

should be explored• Always give users a choice between Serif and Sans-serif

fonts• Always provide an option for lower color contrast

(ideally off-black on light grey)• Use left-aligned (right ragged) text for sections intended

for extended reading

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Recommendations – Web Content

• Websites are reading environments– They just don’t have the same flexibility that an E-Reader

or bookmark app have, but they have more flexibility than a book or magazine

• Learn more about typography– Read Robin Williams’ “The Non-Designers Type Book”

• Play around with different elements and see what you find more readable– Try increasing letter-spacing and font size– Try decreasing line length

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Recommendations – Web Content Continued

• Structure your content (i.e. with headings) and use plain language– This helps individuals with dyslexia scan and use higher

level literacy strategies• Make your sites compatible with syndication/reading

apps– Use RSS even for content you would not normally think of

as syndicated (i.e. pages)– Use good markup– Avoid paginating whole pieces of content (like a single blog

entry or page)

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Thank you

Contact information:

James Jackson

517-884-1420

Jamesedj@msu.edu

usability.msu.edu