Deciding whether to click on links while reading material in hypertext form gives rise to an additional cognitive load and additional distractions, goes a theory championed by Steve Gillmor and Nicholas Carr.
In certain circumstances this is an argument for the “delinkification” of text, they suggest, as this will hopefully bring about increased comprehension.
While I don’t totally agree, I find this analogy rather neat:
The link is, in a way, a technologically advanced form of a footnote. It’s also, distraction-wise, a more violent form of a footnote. Where a footnote gives your brain a gentle nudge, the link gives it a yank. What’s good about a link – its propulsive force – is also what’s bad about it.