As for what is fear biologically speaking, when a person experiences fear, certain areas in their brain such as the amygdala and the hypothalamus are immediately activated and appear to control the first physical response to fear.
Kidney Stones Overview. Kidney stones are small pebbles of salt and mineral in the urine. The most common symptom is severe pain. Most stones pass on their own, but medical procedures are used to remove some kidney stones.
1. What is a kidney stone? Kidney stones are the formation of crystalline structures in the urinary tract (which includes the kidneys, ureters, and bladder). These stones can cause pain, infection, and kidney damage. Stones can be small, from 1 mm to very large, filling up an entire kidney. For pictures of stones, see our stone gallery. 2. Do I have a kidney stone? For patients experiencing their first stone episode, the pain can be so severe and sudden that it stops them in their tracks.