stimulus-specific theory of pain

The stimulus-specific theory of pain proposes that pain arises from specific nerve fibers that are activated by noxious stimuli. This contrasts with older theories that suggested pain was simply a result of excessive stimulation of any nerve fiber. According to the stimulus-specific theory, certain nerve fibers are dedicated to detecting harmful or potentially harmful events, and when these fibers are activated, pain is perceived. These specific fibers are distinct from those that detect non-noxious stimuli like touch or temperature. While this theory applies to many types of pain, particularly in the skin and somatic tissues, it may not fully explain pain originating from internal organs (viscera), where shared nerve fibers might signal both normal organ function and pain.1