Maybe you don't want to buy a new desk or you just prefer the coziness of your warm bed. Either way, you shouldn't study, listen to a lecture, or write a paper from your bed. Not only will this end up hurting your back or neck (posture is important!), but also, research shows that it is harder to focus on your work while sitting in bed and harder to fall asleep at night if you associate your bed as a place to study.