Does lack of sleep impact your teaching?

Can a teacher teach the ABC's if she hasn't gotten her Z's? In a recent study from Ball State University, nearly a quarter of surveyed teachers reported that sleep deprivation "significantly diminished" their teaching skills. The study also suggests that teachers, who average six hours of sleep per night, tend to get less sleep than those in many other professions. Though a lack of sleep has a measurable impact on one's reaction time, memory skills, and mood, among other things, some people maintain that they can wake up refreshed after only a few hours of shut-eye. Do you see a change in your performance depending on the amount of sleep you get? We want to know!