Ferris Jabr at Scientific American reviewed (April 2013) studies of differences in reading comprehension on digital vs paper. Here’s a fascinating note on the value of the 3-dimensionality of book for comprehension, remembering and retrieval:
Beyond treating individual letters as physical objects, the human brain may also perceive a text in its entirety as a kind of physical landscape. When we read, we construct a mental representation of the text in which meaning is anchored to structure. The exact nature of such representations remains unclear, but they are likely similar to the mental maps we create of terrain—such as mountains and trails—and of man-made physical spaces, such as apartments and offices. Both anecdotally and in published studies, people report that when trying to locate a particular piece of written information they often remember where in the text it appeared. [emphasis added]
This locational memory which, for most people nowadays, is linked to position in a codex book, is culturally specific. When rhetoricians wrote about locational memory (the palace of memory system, for example), and linking thoughts and words to particular locations, they was pointing to a similar idea.
In contrast, most screens, e-readers, smartphones and tablets interfere with intuitive navigation of a text and inhibit people from mapping the journey in their minds. A reader of digital text might scroll through a seamless stream of words, tap forward one page at a time or use the search function to immediately locate a particular phrase—but it is difficult to see any one passage in the context of the entire text [PR: physically embodied in a 3-dimensional object].
Then there’s this study, which suggests that PDFs, EPUB files and e-readers generally need to be more readily accessible to our locational memory (rather than requiring a more cerebral word search):
At least a few studies suggest that by limiting the way people navigate texts, screens impair comprehension. In a study published in January 2013 Anne Mangen of the University of Stavanger in Norway and her colleagues asked 72 10th-grade students of similar reading ability to study one narrative and one expository text, each about 1,500 words in length. Half the students read the texts on paper and half read them in pdf files on computers with 15-inch liquid-crystal display (LCD) monitors. …. Based on observations during the study, Mangen thinks that students reading pdf files had a more difficult time finding particular information when referencing the texts. Volunteers on computers could only scroll or click through the pdfs one section at a time, whereas students reading on paper could hold the text in its entirety in their hands and quickly switch between different pages. Because of their easy navigability, paper books and documents may be better suited to absorption in a text. “The ease with which you can find out the beginning, end and everything inbetween and the constant connection to your path, your progress in the text, might be some way of making it less taxing cognitively, so you have more free capacity for comprehension,” Mangen says. [emphasis added]
Some readers like Kindle try to create an on-screen indicator or how far you are into a book–a percentage, a slider or other visual device. Jabr goes on talk about readers not feeling in control (an old point), but I think this feeling is comparable to the comfort some people feel with familiar device–like a remote control. I think the 2-D/3-D divide is more significant. I’m a little skeptical of Jabr’s suggestion that the impermanence of text on screens plays a part–he may be right, and the disappearance of a page for a successive page on a Kindle sometimes disconcerts me, but this might be me as hybrid user. (But when a child’s parent disappears and returns in a game of peek-a-boo, babies learn to overcome that fear of abandonment of that comforting parent, so I wonder whether I need deep reassurance that the the text is still there–but I’m speculating here. More important seems to me the locational issue.) Jabr takes up that issue here:
Paper books also have an immediately discernible size, shape and weight. We might refer to a hardcover edition of War and Peace as a hefty tome or a paperback Heart of Darkness as a slim volume. In contrast, although a digital text has a length—which is sometimes represented with a scroll or progress bar—it has no obvious shape or thickness. An e-reader always weighs the same, regardless of whether you are reading Proust’s magnum opus or one of Hemingway’s short stories. Some researchers have found that these discrepancies create enough “haptic dissonance” to dissuade some people from using e-readers. People expect books to look, feel and even smell a certain way; when they do not, reading sometimes becomes less enjoyable or even unpleasant. For others, the convenience of a slim portable e-reader outweighs any attachment they might have to the feel of paper books.
Many years ago I took tests at the Johnson O’Connor Foundation and discovered that I had a lot of trouble distinguishing distances and 3-dimensions, and I learned that some people excel in 3-dimensions and head into engineering, architecture, craft and machinery and others areas in which translating and quickly comprehending X-Y and Z axes are key. (The tests included putting together a 3-dimensional ‘wiggly block’ puzzle or glancing at and copying a projected slide with dots on a 3-d grid.) For me the transition from 2-dimensions to 3-dimensions was deeply disconcerting, but for others it’s not–in fact, it may even be liberating. Are we replicating in our reading devices the one-size-fits-all approach of so much of our education and consumer products?