2. Sensation: The conscious or subconscious awareness of external or internal stimuli. Perception: The conscious awareness and the interpretation of meaning of sensations.

3. Pain Temperature Light touch Pressure Sense of body and limb position Taste Smell Vision Hearing Balance General Senses vs. Special Senses

4. Mechanoreceptors Thermoreceptors Photoreceptors Chemoreceptors Nociceptors

5. skin, bones, internal organs, joints Naked nerve endings surrounded by one or more layers Pacinian corpuscle Free nerve endings Encapsulated Nerve Endings vs Unencapsulated Nerve Endings Deeper tissue, muscles

6. Free Nerve Endings - Pain & Temperature Merkel’s Discs - Light Touch & Pressure Root Hair Plexuses - Light Touch pain, light touch, and temperature

7. Pacinian Corpuscles - Deep Pressure Meissner’s Corpuscles - Discriminative Touch in Hairless Skin Areas Krause’s End-Bulbs - Discriminative Touch in Mucous Membranes Ruffini’s Corpuscles - Deep Pressure & Stretch (Proprioception)

8. Muscle Spindles - Skeletal Muscle Stretching (Proprioception) Golgi Tendon Organs - Tendon Stretching (Proprioception)

9. Somatic Pain-results from injuries to skin, muscle, joints, tendon vs. Visceral Pain- pain in body organs

10. Referred Pain- felt on the body surface

11. epidermis dermis subcutaneous fat hair follicle hair shaft

12. free nerve endings root hair plexus Meissner’s corpuscles Pacinian corpuscles nerve Krause’s End-Bulb

13. Somatic Sensory Pathway

14. Ascending Spinal Cord Tract

15. Descending Spinal Cord Tract

16. Primary Somatosensory Cortex & Primary Motor Area

17. Primary Sensory Cortex

18. Primary Motor Cortex