Delta waves are seen in:: (A) Deep sleep, (B) REM sleep, (C) Awake state, (D) Stage II nREM sleep
Answer is A. REM sleep is characterized by b waves, the waves actually of ale wakefulness. Hence, REM sleep is also called "paradoxical sleep". Awake state with eyes closed - a waves; with eyes open - b waves. NREM sleep: stage 1 shows periodic sho bursts of a waves.