PSYC 4750 Lecture Notes - Aspirin, Cerebral Cortex, Raphe Nuclei
Document Summary
Somatic sensation also depends on nociceptors (unmyelinated) that signal that body tissue is being damaged or is at risk of being damaged. The information from nociceptors takes a path to the brain that is largely distict from the path taken by mechanoreceptors. Selective activation of nociceptors can lead to the conscious experience of pain. Nociception and pain are not the same thing. Pain is the feeling or the pereception of irritating, sore, stinging, and unbearable sensations arising from a party of the body. Nociception is the sensory process that provides the signals that trigger pain. Nociceptors are activated by stimuli that have the potential to cause tissue damage. Examples are: strong mechanical stimulation, extremes in temperature, oxygen deprivation, and exposure to certain chemicals. The membranes of nociceptors contain ion channels that are activated by these stimuli. The transduction of painful stimuli occurs in the free nerve endings of unmyelinated c fibers and lightly myelinated a fibers.