This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
Dreaming is common in which stage of sleep:September 2008 
Select and explain. 
A. REM, B. NREM 1, C. NREM 2, D. NREM 3
A: REM
Answer: A: REM 
Explanation: Ans. A: REMHumans aroused at a time when they show the EEG characteristics of REM sleep generally repo that they were dreaming, whereas individuals awakened from slow-wave sleep/ NREM do not. This observation and other evidence indicate that REM sleep and dreaming are closely associated. The tooth-grinding (bruxism) that occurs in some individuals is also associated with dreaming.