1. The Senses ST 110

2. Special Senses Organs and accessories related to: Vision Hearing Taste Smell Equilibrium

3. Types of Receptors Chemoreceptors Nociceptors Thermoreceptors Mechanoreceptors Photoreceptors

4. Sensations vs Perceptions Sensations- Feelings that occur when the brain receives sensory impulse from PNS. Perceptions-conscious awareness of sensation after interpretation.

5. Somatic Senses Involve the receptors associated with skin, muscles, joints and visceral organs.

6. Senses Touch- tactile receptors located in the skin or just beneath it. Pressure- stimulation of receptors in deeper tissue

7. Receptors Touch and Pressure Free ends of sensory nerve fibers Meissner’s corpuscles Pacinian corpuscles

8. Senses Cont. Thermal- perceptions of degrees of warmth and coolness Temperature- free nerve endings located beneath skin Heat receptors Cold receptors

9. Senses Cont. Pain- free nerve endings that are stimulated when tissues are damaged. Acute Chronic

10. Acute Pain Occurs very rapidly Not felt in deeper tissues Sharp/stabbing pain

11. Chronic Pain Slower onset Builds slowly in intensity (sec. or min.)

12. Visceral Pain AKA referred pain Pg 194 fig 9-1

13. Stretch Receptors Sensations of lengthening and stretching muscles Golgi tendon organs Muscle spindles

14. Sensation of Sight Eye-sensory and receptor organ that receives images and transmits them to the brain.

15. Eye Terminology Optic Ocular Extraocular Intraocular OD OS

16. Accessory Organs Lacrimal apparatus Eyelids Extrinsic muscles

17. Lacrimal Apparatus Produce and drain lacrimal fluid (tears) from eye Lacrimal gland Excretory lacrimal ducts

18. Eyelids Palpebrae 4 layers Skin Muscle tissue Connective tissue Conjunctiva Protection

19. Extrinsic Muscles Rectus Oblique Pg 196 tbl 9-2

20. Conjunctiva Thin mucous membrane Stratified columnar epithelium Conjunctivitis

21. Structure of Eye Fluid filled hollow sphere 3 layers (tunics) Outer Middle inner

22. The Eye Cornea Iris Pupil Lens

23. The Eye Presbyopia Retina Fovea centralis Aqueous humor

24. The Eye Vitreous Humor Optic disc Sclera Choroid

25. Actions of Eye Accommodation Convergence Emmetropia

26. Visual Acuity 20/20 Snellen Chart 1 st number-distance from the chart (20ft) 2 nd number- deviation from the norm based on ability to read chart

28. Pathology of Eye

29. Glaucoma Increase IOP Loss of vision/blindness

30. Keratoplasty Corneal transplant

31. Inflammation Keratitis Iritis Conjunctivitis

32. Strabismus “cross eyed”

33. Cataract Lens loses transparency “milky”

34. Xerophthlamia Dry eye

35. Procedures Blepharoptosis Drooping of upper eyelid

36. Sensation of Hearing Ear-pick up and amplify sound waves for interpretation Equilibrium 3 regions External Middle Internal

37. External Ear Pinna External Auditory Canal Cerumen

38. Middle Ear Eustachian Tube Tympanic Membrane Mastoid Sinus Ossicles

39. Transmit and amplify sound waves Malleus (hammer) Incus (anvil) Stapes (stirrup)

40. Inner Ear AKA labyrinth Cranial Nerve VIII- transmits info from inner ear to brain

41. Normal Ear Actions Air Conduction Bone Conduction Sensorineural Conduction

42. Ear Pathology

43. Outer Ear Impacted cerumen Otalgia Otitis Otorrhagia

44. Middle Ear Eustachitis Mastoiditis Myringitis Otosclerosis Otitis Media

45. Inner Ear Labryinthitis Meniere’s Syndrome Tinnitus Vertigo

46. Procedures Otoplasty Mastoidectomy Myringotomy Stapedectomy

47. Hearing Loss Deafness Conductive Hearing Loss Noise-Induced Hearing Loss Sensorineural Loss Presbycusis

48. Sensation of Taste Taste bud-modified epithelial cells that function as receptors Contain microvilli Types Sweet Salty Sour Bitter

49. Sensation of Smell Olfactory receptors Nasal cavity Olfactory pathways- Nerve impulses travel through olfactory tract and enter brain Interpreted as specific odors Closely associated with areas of brain important in memories and emotion