Chronic Pain

Pain messages travel along the peripheral nervous system until they reach the spinal cord. There is a theory that there are “gates” on the bundle of nerve fibers in the spinal cord between the peripheral nerves and the brain. These spinal nerve gates control the flow of pain messages from the peripheral nerves to the brain. The brain also controls pain messages by attaching meaning to the personal and social context in which the pain is experienced. Many factors determine how the spinal nerve gates will manage the pain signal. These factors include the intensity of the pain message, competition from other incoming nerve messages and signals from the brain telling the spinal cord to increase or decrease the priority of the pain signal. The meaning attached to the situation seems to be the important difference. In times of anxiety or stress, descending messages from the brain may actually amplify the pain signal at the nerve gate as it moves up the spinal cord. Alternatively, impulses from the brain can “close” the nerve gate, preventing the pain signal from reaching the brain and being experienced as pain.