Nicholas Carr: Mental Calisthenics of Hyperlinks

Back in the 1980s, when schools began investing heavily in computers, there was much enthusiasm about the apparent advantages of digital documents over paper ones. Many educators were convinced that introducing hyperlinks into text displayed on monitors would be a boon to learning. Hypertext would strengthen critical thinking, the argument went, by enabling students to switch easily between different viewpoints. Freed from the lockstep reading demanded by printed pages, readers would make all sorts of new intellectual connections between diverse works. The hyperlink would be a technology of liberation.

By the end of the decade, the enthusiasm was turning to skepticism. Research was painting a fuller, very different picture of the cognitive effects of hypertext. Navigating linked documents, it turned out, entails a lot of mental calisthenics—evaluating hyperlinks, deciding whether to click, adjusting to different formats—that are extraneous to the process of reading. Because it disrupts concentration, such activity weakens comprehension. A 1989 study showed that readers tended just to click around aimlessly when reading something that included hypertext links to other selected pieces of information. A 1990 experiment revealed that some "could not remember what they had and had not read."