PHYL 2041 Lecture Notes - Lecture 3: Noxious Stimulus, Mechanoreceptor, Nociception
18 Oct 2018
School
Department
Course
Professor
Document Summary
October 4, 2018: subdivisions of somatosensory systems: (1) Somatosensory system detects outside information and internal information inside the body. It also can provide information about limb position and movement. Processes information about touch, temperature, and pain. It is detected by 3 groups of sensory receptors (many in the skin). One of the receptors are (cid:862)(cid:373)e(cid:272)ha(cid:374)ore(cid:272)eptors(cid:863) that (cid:272)a(cid:374) dete(cid:272)t tou(cid:272)h, pressure, stret(cid:272)h, or (cid:448)i(cid:271)ratio(cid:374). The(cid:455) (cid:272)a(cid:374) also be found in other tissues such as muscle and tendons, blood vessels, and the inner ear. The second receptor = thermoreceptor, that detects changes in temperature of the external environment, either cold or warm. Third receptor = nociceptor pain sensation can detect any stimuli causing tissue damage, either by extreme temperature change, or noxious mechanical or chemical stimuli. They are conveyed by 3 nerve fibers, which are classified by their myelination and their diameter, and velocity. Normally, larger axon faster action potential than that of a smaller axon: group 1/2:
