I'm sure it does, but moreso I think that it might be more a function of the actual style of language used than it is of the subject matter. For example, if you read any literature from a century ago, you'll likely notice that what we now call run-on sentences are used all over the place. These sentences have a parsing tree that is far deeper and more self-referential than modern authors use, and so in turn likely engages the brain more than a simpler sentence structure would. Of course, this has negative connotations as far as clear communication goes, but it's a good exercise to spend a few weeks reading this kind of material - it definitely becomes noticeably more readable after more exposure.

You'll also likely be familiar with the way that newspaper articles (particularly in tabloids and local rags) have dropped their reading grade-level standards and are using simpler linguistic constructions to help ensure their audience understands. There's probably a bit of a negative feedback loop in there somewhere.