Physiology 2130 Lecture Notes - Postcentral Gyrus, Lamellar Corpuscle, Ear Canal
Document Summary
Receptors: touch, vibration, temperature, pain, proprioception (limb position and movement) Somatic organization on the postcentral gyrus (somatosensory area) going from medial to lateral on the cortex. Outer and middle ear transmit pressure waves from air to fluid (3 ways) Semicircular canal (hair cells, cupula, utricle, saccule with otoliths) Movement detection (1 by semicircular canal, 2 by otolith organs) Homeostasis: detecting changes in external environment and adapting. Several sensory systems: somatosensory (touch, visual system, auditory and vestibular (sense of balance, olfactory (smell, gustatory (taste) How information from the external environment is turned into language understood by brain. External stimuli (energy) heat, light, sound, touch are detected by sensory receptors. Example: mechanical stimulus: touch or vibration causes sensory receptors in the skin to stretch, open ion channels causing depolarization action potential. Chemical stimulus: sour taste binds with receptor on tongue causing depolarization ap. Light energy: absorbed through photoreceptors (rods and cones)