1. Ooops… Before we go on…there are a few things I want to cover that we accidentally skipped over…..

2. 2 The Lens Nearsightedness: A condition in which nearby objects are seen more clearly than distant objects. Farsightedness: A condition in which faraway objects are seen more clearly than near objects.

3. 3 Photoreceptors E.R. Lewis, Y.Y. Zeevi, F.S Werblin, 1969

4. Rods v. Cones Rods Black and white vision Sensitive to light Function well in dim light Not good for color Signal goes to one bipolar cell Very sensitive Cones Color Not effective in dim light That is why it is hard to see color in rooms with dim light

5. 5 Bipolar & Ganglion Cells Bipolar cells receive messages from photoreceptors (rods and cones) and transmit them to ganglion cells, which are last before the the optic nerve.

6. Parallel Processing The processing of several aspects of an object simultaneously. Color MotionForm Depth

7. 7 Parallel Processing Processing of several aspects of the stimulus simultaneously is called parallel processing. The brain divides a visual scene into subdivisions such as color, depth, form and movement etc.

8. Top Down or Bottom Up? Processing that begins at sensory level is bottom up. Processing that begins in the brain (through cognition…thinking) is top down processing Senses detect and minds interpret So….what do you see immediately? What do you see if you keep looking?

9. And Now…We Move On!

10. Color Vision

11. If an apple falls from a tree and no one hears it…does it make a sound??? If a tomato appears red…is it red? No!! It is every color except red!

12. A tomato is NOT red because it rejects (reflects) the long wavelengths of red Light rays are not colored Colors is in the “theater of our minds” and that is why we dream in color!

13. Why is her top green?

14. Light has 3 Characteristics 1.Wavelength (hue/color) 2.Intensity (brightness) 3.Saturation (purity)

15. Colors!Colors! Hue (color) is the dimension of color determined by the wavelength of the light. So…what colors you see are determined by the wavelength And a wavelength, by definition, is the distance from the peak of one wave to the peak of the next. And…humans can only see a small percentage wavelengths This came form NASA…so you all are super-duper smart now…

16. 16 Intensity (Brightness) Intensity Amount of energy in a wave determined by the amplitude. It is related to perceived brightness.

17. 17 Intensity (Brightness) Blue color with varying levels of intensity. As intensity increases or decreases, blue color looks more “washed out” or “darkened.”

18. Trichromatic Theory Three types of cones: Red Blue Green These three types of cones can make millions of combinations of colors. Does not explain afterimages or color blindness well.

19. Opponent-Process theory The sensory receptors come in pairs. Red/Green Yellow/Blue Black/White If one color is stimulated, the other is inhibited.

20. Afterimages

21. What color was the X on the white screen?

23. What color was the + on the white screen?

24. Opponent Process- Afterimage Effect

25. What color was the (whatever shape that was! LOL) on the white screen?

26. Color-Deficient Vision aka…color blindness  Genetic condition  Usually male  People who suffer red-green blindness have trouble perceiving the number within the design