Chapter 7
 Eyes and Ears - Outline
Return to Chapter Index

Return to Main Index

I. The eyes
     A. Importance of vision
     B. Image formation and vision
     C. Deterrents to clear vision
          1. Poor focusing
          2. Poor lighting
          3. Nervous system malfunction
II. Forming images - eye components, functions, and age changes
     A. Conjunctiva
     B. Cornea
     C. Iris and pupil
     D. Ciliary body
     E. Lens and suspensory ligaments
          1. Transparency
          2. Opacities
          3. Shape
          4. Elasticity
          5. Presbyopia
     F. Aqueous humor
     G. Vitreous humor
          1. Floaters
          2. Flashers
III. Accommodation
     A. Process
     B. Age changes
IV. Retina
     A. Layers and regions
     B. Cones
     C. Rods
     D. Age changes
          1. Cones
          2. Rods
          3. Processing neurons
          4. Pigmented epithelium and Bruch's membrane
          5. Free radicals in the eye
V. Other eye components - structure, functions, and age changes
     A. Choroid
     B. Sclera
     C. External muscles
     D. Adipose tissue
     E. Eyelids
     F. Lacrimal gland
VI. Two eyes
     A. Advantages
          1. Field of view
          2. Depth perception
     B. Depth perception (binocular vision)
          1. Process
          2. Age changes
VII. Age changes in vision
     A. Light intensity
          1. Declining sensitivity
          2. Declining adaptability
     B. Quality of light - glare
     C. Visual acuity
          1. Close objects
          2. Distant objects
          3. Moving objects
     D. Depth perception (binocular vision)
     E. Field of view
     F. Optimizing vision
VIII. Diseases of the eyes
     A. Minor diseases
          1. Lacrimal fluid
          2. Eye muscles
     B. Cataracts
          1. Incidence
          2. Causes and effects
          3. Prevention and treatment
     C. Age-related macular degeneration
          1. Incidence
          2. Causes and effects
          3. Treatment
     D. Glaucoma
          1. Open-angle glaucoma
          2. Angle-closure glaucoma
          3. Secondary glaucoma
     E. Diabetic retinopathy
          1. Incidence
          2. Causes and effects
          3. Prevention and treatment
IX. The ears - monitoring four conditions
X. Hearing - structures, functions, and age changes
     A. External ear
          1. Pinna
          2. Ear drum
          3. Cerumen (ear wax)
     B. Middle ear
          1. Ear bones
          2. Eustachian tube
     C. Inner ear - fluids, membranes, and neurons
     D. Localizing sound
     E. Central nervous system
XI. Disorders in hearing
     A. Presbycusis
          1. Incidence
          2. Effects
          3. Prevention and compensatory techniques
     B. Tinnitus
XII. Detecting other stimuli
     A. Gravity and changes in speed
     B. Rotation
     C. Age changes (gravity, changes in speed, and rotation
     D. Dizziness and vertigo

Return to Top of Page

Return to Chapter Index

Return to Main Index

©  Copyright 2020: Augustine G. DiGiovanna, Ph.D., Salisbury University, Maryland
The materials on this site are licensed under CC BY-NC-SA 4.0

Attribution-NonCommercial-ShareAlike
This license requires that reusers give credit to the creator. It allows reusers to distribute, remix, adapt, and build upon the material in any medium or format, for noncommercial purposes only. If others modify or adapt the material, they must license the modified material under identical terms.
Previous print editions of the text Human Aging: Biological Perspectives are © Copyright 2000, 1994 by The McGraw-Hill Companies, Inc. and 2020 by Augustine DiGiovanna.
View License Deed | View Legal Code