Kretzschmar and Schlesewsky say that, to the best of their knowledge, no one has really tried to answer this question -- if there's such a trail between subjective impressions about ease of reading and objective measurements. That alone, they say, makes their study unique.
In two groups of young (between ages of 21 and 34) and old (60 to 77) readers, the researchers measured two parameters to identify the amount of cognitive processing required as each participant read uniform text on a paper page, an e-reader and a tablet computer.
Using eye-tracking technology, the first parameter measured was time required for visual fixation of text. Secondly, to gauge cognitive effort, the researchers used EEG sensors to measure theta band voltage density in the brain, known to co-vary with memory encoding and retrieval.
"In our field, EEG and eye movements in reading are the two best methods you can use because both have a very high temporal resolution," said Kretzschmar. "So you're able to say exactly at which moment in time or at what position in the sentence or word there is some processing disruption."
Prior to the study, a questionnaire showed that participants of both age brackets overwhelmingly chose the paper page over the other two e-devices as their preferred reading medium. The study results, however, showed no bias. In fact, they told a different tale.
Not only did comprehension accuracy show no difference across the three media for either group, young participants showed comparable text fixation durations and EEG theta activity for all three devices. Perhaps most myth-busting is that the older adults spent less time fixating on text and showed lower brain activity (effort) when using a tablet, as compared to the other devices.
Perhaps the most striking finding, the study states, was "the complete lack of a correspondence between the offline measures collected (comprehension accuracy and subjective ratings) and the online measures of reading effort."
The bottom line: "Our results thus indicate that negative subjective assessments of readability for e-books and other digital texts are not a reflection of real-time information processing demands."
"I am totally surprised that so many people argue from an emotional perspective that reading on an e-reader or iPad is more unpleasant than reading a book and then combine this statement that it's more difficult and complex to read on this new digital media," said Schlesewsky.
"In the UK, as well in America, people are more open and more interested to see and think about the data," he added. "In Germany, people don't think about the data, they think about the consequences based on habit and emotion."
Kretzschmar says the study could encourage the young and old to go digital.
"Maybe it's a good thing to also know for the future," she quipped, "that in 40 years time you can increase you reading speed" by reading on a tablet.