"...it was exhausting: a continuous period of forced engagement, with no relief in the form of time when my attention could flag or I could doodle in a notebook undetected. Instead, my focus was directed relentlessly by the platform, and because it looked like my professor and fellow edu-nauts were staring at me, I was reluctant to ever let my gaze stray from the screen... I felt my attention snapped back to the narrow issue at hand, because I had to answer a quiz question or articulate a position. I was forced, in effect, to learn."

This reminds me of the experience of playing video games...