[mapkkk]

I'll (lightheartedly) come to their defense to say that this is how I and a lot of my peers made it through med school. The wetness of the page indeed unlocked some supressed memories.

I think it's a combination of a ritual and some sort of somewhat-more-elevated engagement (or wishing thereof) with the material. Somewhere between meditative ritual and attention aid. I doubt it helped much, if at all - except for Stabilo; they were the true winners.

[gtg239a]

I remember as an undergrad watching some philosophy majors do this with their reading and their explanation was that it helps them track reading progress. And to your point, that tactile act probably helps a lot with engagement!

The unfortunate part is that you can't then unhighlight a passage.

[killerstorm]

Yeah... There was no "reading" in our ancestral environment, it's rather unnatural for a human brain to focus on the page where nothing happens. Some people can adapt to that, other people need stimulation of some kind.

And it's not like some ADHD thing which is new. E.g. Stanisław Lem as a kid: "But because the act of reading was too passive, too simple, I would rest a chair leg on my calf or knee or foot and with little movements keep the chair at the very brink of falling."