HSC 350 Study Guide - Midterm Guide: Sodium Channel, Dorsal Root Ganglion, Substantia Gelatinosa Of Rolando
Document Summary
Pain: is the feeling or perception of an unpleasant sensory and emotional experience associated with actual or potential tissue damage. Nociception: is the sensory neural processes of encoding and processing noxious stimuli. Nociception depends on specifically dedicated receptors and pathways distinct from the sensory processing of ordinary mechanical stimulation. Nociceptors: are unspecialized free nerve cell endings that initiate the sensation of pain. 3 major classes of nociceptors in the skin: a mechanosensitive nociceptors (mechanical, a thermal nociceptors (temperature activated, c fiber polymodal nociceptors (mechanical, chemical and thermal) These 3 classes work together to contribute to the perception of pain. Nociceptive information is sent relatively slow but there are fast and slow pain pathways. C fiber group are unmyelinated axons (slower conducting speed 2m/s) 2 categories of pain perception: first pain mediated by fast a axons (fast and sharp, second pain mediated by slow c fibers (delayed, longer-lasting and dull) Noxious stimuli depolarize nociceptor endings to generate action potentials.
