This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous system, Subject name: Physiology
[{'content': 'Which of the following is observed during sleep induction? \nSelect and explain. \nA. | Norepinephrine and serotonin, B. | Acetyl Choline, C. | Histamine, D. | GABA', 'role': 'user'}, {'content': "Answer: B \nExplanation: The cholinergic neurons in pontine reticular formation on stimulation, induce sleep. When the activity of norepinephrine and serotonin containing neurons (locus coeruleus and raphe nuclei) is dominant, there is a reduced level of activity in acetylcholine-containing neurons in the pontine reticular formation leading to wakefulness. The reverse of this pattern leads to REM sleep. A more even balance in the activity of these groups of neurons is associated with NREM sleep. Ref: Ganong's Review of Medical Physiology 25th edition Pgno: 279", 'role': 'assistant'}]