  Highlighted text in the Internet (i.e. Hypertext) is predominantly blue and
underlined. The percept of these hypertext characteristics were heavily
questioned by applied research and empirical tests resulted in inconclusive
results. The ability to identify blue text in foveal and parafoveal vision was
identified as potentially constrained by the low number of foveally centered
blue light sensitive retinal cells. The present study investigates if foveal
and parafoveal perceptibility of hypertext is reduced during reading. A
silent-sentence reading study with simultaneous eye movement recordings and the
invisible boundary paradigm, which allows the investigation of foveal and
parafoveal perceptibility, separately, was realized. Target words in sentences
were presented in either black or blue and either underlined or normal. No
effect of color and underlining, but a preview benefit could be detected for
first pass reading measures (comparing fixation times after degraded vs. un-
degraded parafoveal previews). Fixation time measures that included re-reading
(i.e., total viewing times) showed, in addition to a preview effect, a reduced
fixation time for not highlighted (black not underlined) in contrast to
highlighted target words (either blue or underlined or both). Thus, the present
pattern reflects no detectable perceptual disadvantage of hyperlink stimuli but
increased attraction of attention resources, after first pass reading, through
highlighting. Blue or underlined text allows readers to easily perceive
hypertext and at the same time readers re-visited hypertext longer as a
consequence of highlighting. On the basis of the present evidence blue
hypertext can be safely recommended to web designers for future use.
