Answer to Question 1
Raynaud's phenomenon (RP) involves spasms (vasoconstriction) of the arteries and arterioles of the fingers and toes. The spasms, typically induced by cold exposure or emotional stress, cause reduced blood flow to the area, which leads first to skin blanching (i.e., reduced coloration), then cyanosis (i.e., a bluish color due to lack of oxygen), and finally redness upon reperfusion (i.e., blood restoration) of the digits. Spasmodic episodes may last minutes or hours and may involve burning or cold sensations in the affected areas.
Answer to Question 2
Possible mechanisms include changes in blood flow, the central nervous system, the autonomic nervous system, or neurotransmitters disrupting the migraine's pathophysiology.
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