PSYC 2410 Chapter : Somatosensation.docx

• School: University of Guelph
• Department: Psychology
• Course: PSYC 2410
• Professor: Elena Choleris

Document Summary

Sensations form the surface and the inside of the body. Exteroceptive system: external stimuli applied to the skin (mechanical, nociceptive (pain), and thermal) Proprioceptive system: stimuli on body position which comes from muscles, joints and organs of balance (e. g. , vestibular system in inner ear) Interoceptive system: provides general information about the conditions within your body (e. g. blood pressure, internal temperature; autonomic sensory information) 4 receptors: free nerve endings, pacinian corpuscles, merkel s disks, ruffini ending. Faster adaptation: if continuous stimulation, receptors will eventually stop responding, free nerve endings: simplest. Nerves that end very close to surface. Respond best to temperature changes (heat and cold) and pain. Apply hot or cold stimulation to see if there is a difference in activity (otherwise, the receptors, anatomically, look the same for hot and cold: pacinian corpuscles: largest and deepest. Look like onion with multiple layers of membrane. Respond to sudden skin displacement more than to constant stimulations.