This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Introduction to Central Nervous System, Subject name: Physiology
[{'content': 'Among the areas mentioned, the highest number of noradrenergic neurons is present in: \nSelect and explain. \nA. Locus ceruleus, B. Nucleus raphe magnus, C. Periaqueductal grey, D. Medial longitudinal fasciculus', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Locus coeruleus has max number of nor-adrenergic neurons Nucleus raphe magnus has max number of serotonergic neurons Periaqueductal grey has max number of enkephalinic neurons Medial longitudinal fasciculus has max number of Dopaminergic neurons It is implicated in reward & addictive behavior But now nucleus accumbens is said to be involved in reward & addictive behavior', 'role': 'assistant'}]