Kate Garland, a lecturer in psychology at the University of Leicester in England, is one of the few scientists who has studied this question and reviewed the data. She found that when the exact same material is presented in both media, there is no measurable difference in student performance.
However, there are some subtle distinctions that favor print, which may matter in the long run. In one study involving psychology students, the medium did seem to matter. “We bombarded poor psychology students with economics that they didn’t know,” she says. Two differences emerged. First, more repetition was required with computer reading to impart the same information.
Second, the book readers seemed to digest the material more fully. Garland explains that when you recall something, you either “know” it and it just “comes to you” — without necessarily consciously recalling the context in which you learned it — or you “remember” it by cuing yourself about that context and then arriving at the answer. “Knowing” is better because you can recall the important facts faster and seemingly effortlessly.
“What we found was that people on paper started to ‘know’ the material more quickly over the passage of time,” says Garland. “It took longer and [required] more repeated testing to get into that knowing state [with the computer reading, but] eventually the people who did it on the computer caught up with the people who [were reading] on paper.”
Context and landmarks may actually be important to going from “remembering” to “knowing.” The more associations a particular memory can trigger, the more easily it tends to be recalled. Consequently, seemingly irrelevant factors like remembering whether you read something at the top or the bottom of page — or whether it was on the right or left hand side of a two-page spread or near a graphic — can help cement material in mind.