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What is Stimulation of which of the following areas of brain is experimentally used to control intractable pain and explain in detail?
ganong's review of medical physiology 24th edition . *mesencephalic periaqueductal gray(PAG) is pa of descending pathway that modulates pain transmission by inhibition of primary afferent transmissiion in the dorsal horn of spinalcord *PAG neurons project directly to and activate two groups of neurons in brainstem:neurons in nucleus raphe magnus and in rostral ventromedial medulla . *neurons from both region project to dorsal horn and inhibit dorsal horn neuron activity.