Point:Counterpoint: Sympathetic activity does/does not influence cerebral blood flow. Point: Sympathetic activity does influence cerebral blood flow.

Cerebral arteries are abundantly innervated by sympathetic fibers, but their influence on cerebral vessels was held unimportant for almost a century ([2][1], [20][2]). Whether there is sympathetic influence on cerebral blood flow (CBF) is important in the management of hypotensive patients. If there

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