8_Unit2.3_Somatosensation copy

What about sensations such as itch tickle dampness

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Unformatted text preview: sure, heat, cold, and pain. •  What about ‘sensations’ such as itch, tickle, dampness, texture, and firmness? 3 7/4/12 Cutaneous Sensation •  Free receptors vs. encapsulated receptors •  Encapsulated endings: primarily mechanoreceptors that inform about object movement and frictions. •  Free endings: primarily act as nociceptors Cutaneous Sensation Epidermis Dermis Cutaneous Sensation - Pain impulse means action potential reflexes 4 7/4/12 cutanious senstaion used for grasping Cutaneous Sensation - Grasping Cutaneous Sensation and Postural Control skating takes cutanious sensation aswell!!!!----when you lose it it makes moving through out the system hard. Cane for Light Touch? Light Touch Paradigm Ultrasound Receivers Auditory Alarm > 1 Newton Touch Plate Force Platform 5 7/4/12 Cutaneous Sensation and Postural Control no touch makes you sway more Light Touch = Heavy Touch COM Displacement (cm) eyes closed makes you sway more 1 eyes closed eyes open 0.75 so you are more stable through somatosensory sensation that vision. 0.5 0.25 0 no light heavy Touch Condition Jeka & Lackner (1994) Exp Brain Research, 100, 495-502 Tactile Information for Complex Skills touching a wave is not mechanical really- like it mostly just to for info you do it unconsiously Sensory Polyneuropathy (19 years) 50 year old female! •  Absent (Distal to ear lobe level) !  Tendon reflexes, light and crude touch, vibration, kinesthesia, position sense !  Sural n. biopsy: Large A-b myelinated fibers (>6.5um); 40% of normal density !  •  Ambulation, sense of spatial orientation !  Sensory potentials in arms and feet Normal !  Pain, Temperature !  Motor conduction velocity !  Strength skip 6 7/4/12 skip Somatosensory Loss summary Somatosensory System Somatosensation Cutaneous Sensation skin Pacinian, Meissner, Merkel, Ruffini and Free endings Muscles Muscle spindles and Golgi tendon organs Joints Type 1, 2, 3 and 4 Proprioception Proprioception know muscle spindles well --in muscles Proprioceptors---mechano respectors •  Sensation...
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This document was uploaded on 03/28/2014 for the course KNES 385 at Maryland.

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