While heart attack cases are reported throughout the year, the cold weather can heighten the possibility of heart attacks, especially in people with hypertension. "In winter, the blood vessels of the ...

Vasoconstriction - blood vessels near the surface of the skin called arterioles constrict (become narrower) allowing less blood to the skin surface and therefore less heat is lost by radiation.

Using a new plethysmographic technique to measure peripheral arterial tone (PAT), we report here that REM sleep in humans is associated with considerable peripheral vasoconstriction. The apparatus ...

Ways in which the body can increase temperature are: Vasoconstriction - blood vessels are restricted and blood flow to skin stops so less heat is lost. Hair erector muscles contract - hairs stand ...