DRS2012 Bangkok Proceedings Vol 4 - Design Research Society

1870 Conference Proceedings
Typography Matters when Designing Onscreen Reading Materials for Dyslexic Learners
images of printed books and turning page animations 1 . This practice is not likely to lead
to solutions that will enhance the onscreen reading experience and may be
counterproductive to how readers use this technology. Although it is logical to begin with
what we know, e.g. designing for print media, it cannot be assumed that these solutions
will work onscreen merely because they work in print. Perhaps the most striking example
can be seen in the difference in how typographic designers think about the line length of
texts. Typographic convention for traditional print media states that an ideal line length is
between 50 and 70 characters and this is rarely, if ever, argued. However, readers have
shown that they are able to read text passages presented onscreen faster with longer line
lengths, which goes as far as reading continuous texts set with lines as long as 100
characters faster than those set at 25 characters per line (Dyson and Haselgrove, 2001;
Dyson, 2004). This may be due to factors that are inherent in the medium such as
scrolling and reading distance (Dyson, 2004), but nonetheless these findings raise
questions about any assumptions placed on whether there are similarities between
reading from digital and print media. These are issues that need further exploration
generally, but also whether the same patterns are seen in developing readers more
specifically.
Studies on early forms of digital display technology (Dillon, 1992) that compared the
influence of onscreen presentations to print found that when reading from screen reading
rate was slower, accuracy was reduced, and fatigue and ocular discomfort increased.
These findings may no longer be influential since these effects are likely, at least in part,
due to low-resolution screens and the limitations of the technology of that time. Even
Dillon (1992) himself, who provided a review of this early research, recognized that when
screens used for reading are able to render texts at a resolution similar to that of printed
materials, differences in reading speed and accuracy that were seen with the lowresolution
screens are likely to disappear. Although we are still not seeing screen
resolutions that are close to that of print – 1,200 to 2400dpi is common for print as
opposed to 100 to 200dpi for screen (Bias et al., 2010) – with font designs 2 optimized for
screen and the understanding that letterforms that have a larger x-height and more white
space within the letters are more legible for children when reading onscreen (Bernard, et
al., 2002), it seems we are beginning to move in the right direction. It is clear that some of
the issues relating to the constraints of the medium are being identified and addressed
and with further research it may be possible that next to no legibility or comfort
differences are seen between onscreen and print reading materials, even without equality
in resolution.
As mentioned, dyslexia is caused by a deficit in verbal language processing; however,
many sufferers may also experience physical discomfort in the form of visual stress when
reading (Irlen, 2005; Singleton, 2009). Visual stress is believed to be associated with
sensitivity to particular light frequencies and can cause symptoms such as, eye-strain that
can lead to headaches (in some cases migraines) and textual illusions that include letter
distortion, blurring, transient text, and colored halos. The symptoms tend to get worse
with more time spent reading and can interfere with a reader’s ability to see the text
accurately (Wilkins, 1995; Irlen, 2005). However, symptoms have been reduced in
studies that look at the use of colored filters, most commonly in the form of transparent
overlays and lenses (Wilkins, 1995; 2003; Wilkins, et al., 2004; Irlen, 2005). The use of
1 Kerr and Symons (2006) reported that physical page properties that readers are accustomed to in traditional
printed books may be useful in developing a spatial representation of the text (i.e. where specific content
appears on the page) and that this ability to develop a spatial representation of texts may contribute to a
reader’s comprehension of the content. With onscreen reading materials that relay on scrolling rather than page
turning this spatial representation may be lost; nonetheless, it is suggested that it may be more advantageous to
continue to explore the potential of onscreen formatting because without a thorough understanding of the
medium we cannot know for sure where benefits lie.
2 For example, the fonts designed for Microsoft’s ClearType consider features such as letter shape, antialiasing,
and hinting to improve legibility while working within the constraints of LCD technology (Larson, 2007).