Chapter 10 SPECIAL SENSES

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. State Standards Health Science 8) Outline basic concepts of normal structure and function of all body systems, and explain how homeostasis is maintained. 19) Understand principles of and successfully perform skills related to Medical Assisting Skills, incorporating rubrics from textbooks or clinical standards of practice for the following b. Screening for vision problems © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

Objectives Students will demonstrate knowledge of anatomy of the eye, ear, nose, and tongue. Students will perform vision assessments to screen for vision problems. Students will explore sensory experiences of the different sensory organs through lab activities

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. The eye 1 inch sphere Protected by the orbital socket of the skull, eyebrows, eyelids, and lashes Continuously bathed in tears from the lacrimal duct in the inner corner of the eye © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. THE EYE © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. Discussion With a partner discuss… What is purpose of tears? What would happen to our eyes without tears? Why do we blink? Is this a voluntary or involuntary reflex? © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. THE EYE Sclera - outer layer or white of eye Cornea - center and front of sclera Choroid coat - middle of the eye Iris - colored, muscular part Pupil - circular opening in iris Lens - behind iris and pupil Retina - innermost (third) coat © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. THE EYE © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. PATHWAY OF VISION © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

Labeling Draw an eye and label these parts…. Sclera Cornea Pupil Lens Retina Optic nerve Add this to your notes.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. Common Vision defects Presbyopia- decreased ability to focus on close objects Hyperopia- (farsightedness)- objects must be moved farther away to be clear Myopia- (nearsightedness)- objects must be brought closer to be clear Amblyopia- dimness of vision © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

Common Vision defects cont. Astigmatism- irregularly curved cornea Diplopia- blurred vision Strabismus-crossed eyes (due to muscle weakness) © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

Screening for Vision problems Common screening tools include… Snellen Chart- assess distance Reading newsprint- assess near vision Color testing- color bars on the Snellen chart Manual Peripheral Vision screening © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. Snellen Chart https://www.youtube.com/watch?v=kMwy06mAV5U Colored lines are used to check for presence of colored blindness © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. Reading Newsprint Tests near vision by measuring the ability to read newsprint at a distance of 14 inches (35 cm). Determines if hyperopia or myopia is present © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

Steps to Checking Peripheral Vision Assesses peripheral vision by determining when an object comes into sight. a. Seats client 2 to 3 feet away from self b. Has client cover one eye and gaze straight ahead. c. Begins well outside normal peripheral vision and brings object to the center of the visual fields. d. Repeats in all 4 visual fields, clockwise. © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

Activity With a partner you will be checking each others vision using a grading rubric. You will be performing the following tests… Distance- Snellen chart Color- Snellen Chart Near- newsprint Peripheral- manual peripheral testing Document the results of your testing and determine if your partner has any visual defects. *if you wear glasses (complete activity with glasses and without to observe the difference) *you will be performing Snellen chart Check offs as part of your test over special senses.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. THE EAR © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. THE EAR The outer ear (Pinna) collects sound waves and directs them into auditory canal that leads to the eardrum Glands that secrete wax (cerumen) Discussion: Discuss with a partner why we need cerumen. Research: Applying what you know about the types of tissue, what tissue is the outer part of our ear made of? © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. The middle ear Cavity in the temporal bone connects to the throat by the Eustachian tube equalizes air pressure Contains 3 tiny bones that transmit sound waves to the ear drum Hammer Anvil Stirrup © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. Discussion Discuss with your partner Why would we need the ability to equalize pressure between our ear canal and throat? What are examples of when this happens? © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. THE NOSE The human nose can detect about 10,000 different smells Odor molecules that pass through the nose get warmed and moistened. © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. THE TONGUE The tongue is a mass of muscle tissue with structures called papillae Taste buds cover the papilla, which are stimulated by sweet, sour, salty, and bitter tastes © 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc.

© 2004 Delmar Learning, a Division of Thomson Learning, Inc. Group Activity Read the Smell and Taste lab information located on the website. In your small groups you will be completing sensory stations and answering the questions located around the room… 1. How is your sense of smell? 2. Smell Accommodation 3. The link between taste and smell 4. Taste sensations When you are finished answer the Review questions located at the bottom individually © 2004 Delmar Learning, a Division of Thomson Learning, Inc.