i find that studying lying down or even with music really distracts me.
i used to do really badly study wise, was failing completely at college then went about studying how to study and learn and focus and somewhere it said it was bad to study lying down so i guess i took it on as a habit
in the yogic sense you should always be in ease but that doesn't mean you shouldn't sometimes go through discomfort if it'll better you later on. on a technical level, you spine being straight allows spinal fluid and, on a more hokey hippy level, shakti or energy to flow better and you'll do better.
just wrote an article on focus, would be cool if you checked it out and commented
How to Focus: Get Things Done and Be Free
much love
alex