";s:4:"text";s:2766:"Many genes contribute to pain perception, and mutations in one or more pain-related genes account for some of the variability of each individual’s pain experiences. This theory suggests that the spinal cord contains a neurological "gate" that either blocks pain signals or allows them to continue on to the brain. It is called the gate control theory of pain , and it was initially developed by Ronald Melzack and Patrick Wall. Some people born genetically insensate to pain—meaning they cannot feel pain—have a mutation in part of a gene that plays a role in electrical activity of nerve cells. The different ways people experience pain. This chapter provides an analysis of the differences between nociception and pain, on the basis of the anatomy of the peripheral and central nervous systems and the role of nociceptors in pain perception. 2, 7, 8 The overall literature suggests that exaggerated psychosocial responses to acute pain are maladaptive and likely to intensify the pain experience and impede recovery. Maya consulted her physician about severe back pain. The International Association for Study of Pain (IASP) defines pain as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.” It further states that “pain is always subjective, and each individual learns the application of the word through experiences related to injury in early life.” It includes discussion of the concept of persistent pain and presents information on the embryologic origins of pain. A pain-induced stress response is elicited by a magnified perception of pain as threatening or dangerous (catastrophizing) and often manifests as fear and avoidance of pain-provoking stimuli. Due to the observations that raised questions, a new theory of pain was developed in the early 1960s to account for the clinically recognized importance of the mind and brain in pain perception.