1. Color Blindness “Color Vision Deficiency”

2. What is it? Our eyes determine Color the wavelength of a light seen Photoreceptors send Chemical messages to brain Most of us have 3 types of Cones in the Eye – Red, Green and Blue – Called “Trichromatic”

3. Types of Color Blindness Anomalous trichromacy – Have all 3 cones – One is defective – Least severe Dichromatic vision – Missing one cone Monochromacy – All cones are defective – See only black, white and gray How ColorBlindness Works How ColorBlindness Works

4. How does a person become colorblind? Most are inherited at birth – X – Linked Recessive Aging Injury to the eye Side effect of Medicines Eye Disorders – Glaucoma, macular degeneration, cataracts, diabetic retinapothy

5. Are dogs Colorblind? Dogs are Red/Green color deficient They only have 2 cones in their retina – Blue and yellow Can still perceive a red ball from a green one if there is enough brightness

6. Testing for colorblindness Ishihara Test – Colored plates – Diagnose red/green colorblindess – Not the most accurate Anomaloscope – Match colors on a screen by adjusting the light – Most accurate – Test online Test online

7. Color Blindness Testing Cont’d Farnsworth Munsell 100 Hue Test – Arranging colored chips by order of hue – Online Test Online Test

8. How a Color Deficient Person sees the World http://colorvisiontestin g.com/what%20colorbli nd%20people%20see.ht m http://colorvisiontestin g.com/what%20colorbli nd%20people%20see.ht m

9. YOU WILL TAKE THE ISHIHARA TEST THE FIRST 3 SLIDES ARE DEMOS TO SHOW YOU WHAT TO EXPECT

10. Answer: Everyone should be able to see a circle, star, and square in the demonstration plate.

11. Colorblind individuals should see the yellow square. Color normal individuals should see the yellow square and a "faint" brown circle.

12. Colorblind individuals should see nothing. Color normal individuals should see a "faint" brown boat.

13. Continue Ishihara test online http://www.colour- blindness.com/colour-blindness- tests/ishihara-colour-test-plates/

14. ISHIHARA TEST YOU CAN DO AT HOME http://www.color-blindness.com/ishihara-38-plates-cvd- test/#prettyPhoto