Acute pain activates receptors (i.e. "microphones” or "call buttons”) that transfer information via the spinal cord and other hubs to the central nervous system, or your brain. Once inside the brain, this information is interpreted through a number of complex processes. The resulting interpretation may be the sensation of pain, combined with a certain reaction (burning, stinging, jerking, throbbing, etc.) that is felt in a more or less precise area of the body. Pain may also be repressed by the brain, e.g. via distraction, exertion or concentration on an interesting job, or a more vital function such as fleeing danger or experiencing shock after an accident. Chronic pain can arise from acute pain, but several complex criteria must first be met.