VISION

1. VISION HUE • 1) ________: the dimension of visual experience specified by color names • The sun produces white light and, sometimes moisture in the air act like a prism (RAINBOW)

2. VISION BRIGHTNESS • 2) __________________: lightness or luminance; the dimension of visual experience related to the amount of light emitted from or reflected by an object • The more light an object reflects, the brighter it appears • Yellows appear brighter than reds and blues when their reflective qualities are identical

3. BRIGHTNESS ILLUSION

6. VISION • 3) SATURATION: the dimension of visual experience related to the complexity of light AKA ________________ The more saturated, the more PURE WHITE light = NO SATURATION COLORFULNESS

7. I SEE YOU! – PARTS OF THE EYE

9. Functions of the Eye • CORNEA –Protects the eye • LENS - Focuses light from objects that are close by or far away • IRIS - Gives your eyes their color • PUPIL - Dilates and contracts to control levels of light

10. RETINA RETINA • The ______________ • Contains visual receptors • Acts as a movie screen • The retina is actually not part of the eye but an extension of the brain • EXAMPLE: Images projected on the retina are upside down, but the brain views them as right side up

11. Retinal Receptors • There are 2 kinds of visual receptors located in your retina • 1) __________: Allow us to see color • THINK: CONES = COLOR • 2) __________:Allow us to see at night and to use peripheral vision but are NOT sensitive to color CONES RODS

12. Rods vs. Cones FOVEA YES NO

13. The Retina • A magnified image of cones and rods in the retina of a human eye

14. Are You Afraid of the Dark? DARK ADAPTATION • ____________________: the process by which visual receptors become maximally sensitive to dim light • Cones adapt quickly (10 minutes or so) • Rods adapt slowly but are more sensitive

15. BEAR GRYLLS

16. How is Everything Connected? • Rods and cones → Neurons → _________________. • GANGLION CELLS are neurons that “GANG UP” in the retina • Their axons make up the optic nerve GANGLION CELLS

17. HUMAN RESPONSES • It is believed that humans have a highly specialized _______________ • People suffering from brain damage are still able to recognize faces • EXAMPLE: VEGETABLE MAN "FACE MODULE"

18. VEGETABLE MAN

19. Can you find all six faces?!?

20. How Do We See Colors? • There are 2 processes which account for our ability to see color • 1) ____________________ • AKA: Young Helmholtz Theory; • Occurs in the retina TRICHROMATIC THEORY

21. TRICHROMATIC THEORY • There are 3 basic types of cones in the retina • One responds to the color ________ • One responds to the color ________ • One responds to the color ________ • All other colors are formed from a combination of these three BLUE GREEN RED

22. COLOR BLIND OR COLOR DEFICIENT? • Is it possible to be completely color blind? _____, but it is ________ • Cones in the retina are absent or malfunction • Many species of animals are completely color blind RARE YES

23. COLOR DEFICIENCY • Most “colorblind” people are unable to differentiate _________ & ______ • In rarer cases, the opposite is true • Who does it affect? • 8% of white men • 5% of Asian men • 3% black and Native American men • It is VERY RARE in women RED GREEN

24. COLOR VISION SCREENING • FOR EACH QUESTION, ANSWER: • NEVER (OR ALMOST NEVER) • SELDOM • OCCASIONALLY • FREQUENTLY • ALWAYS (OR MOST ALWAYS)

25. 1. DO YOU HAVE DIFFICULTY DISCRIMINATING BETWEEN YELLOW AND ORANGE?N, S, O, F, or A

26. 2. DO YOU HAVE DIFFICULTY DISCRIMINATING BETWEEN YELLOW AND GREEN? N, S, O, F, or A

27. 3. DO YOU HAVE DIFFICULTY DISCRIMINATING BETWEEN GRAY AND BLUE-GREEN? N, S, O, F, or A

28. 4. DO YOU HAVE DIFFICULTY DISCRIMINATING BETWEEN RED AND BROWN? N, S, O, F, or A

29. 5. DO YOU HAVE DIFFICULTY DISCRIMINATING BETWEEN GREEN AND BROWN? N, S, O, F, or A

30. 6. DO YOU HAVE DIFFICULTY DISCRIMINATING BETWEEN PALE GREEN AND PALE RED? N, S, O, F, or A

31. 7. DO YOU HAVE DIFFICULTY DISCRIMINATING BETWEEN BLUE AND PURPLE? N, S, O, F, or A

32. 8. DO THE COLOR NAMES THAT YOU USE DISAGREE WITH THOSE THAT OTHER PEOPLE USE? N, S, O, F, or A

33. 9. ARE THE COLORS OF THE TRAFFIC LIGHTS DIFFICULT TO DISTINGUISH? N, S, O, F, or A

34. 10. DO YOU TEND TO CONFUSE COLORS? N, S, O, F, or A

35. RESULTS TO TALLY YOUR SCORE: • GIVE YOURSELF: • 1 Point for each Never • 2 Points for each Seldom • 3 Points for each Occasionally • 4 Points for each Frequently • 5 Points for each Always • THEN, ADD YOUR SCORE

36. RESULTS • If you scored 16 or higher, you have an 81% likelihood of failing a standard screening test for color vision. • If your score is in this range, you might want to get your color vision tested by a doctor

43. Our Next Act… OPPONENT-PROCESS THEORY • 2) ______________________ • Opponent-Process cells and brain neurons respond to certain waves and are inhibited from firing by other waves

44. ANTAGONISTIC COLORS Cells that fire in response to a color stop firing when the color is removed and vice versa _____________________ = Antagonistic _____________________ = Antagonistic _____________________ = Antagonistic Red and Green Blue and Yellow Black and White

45. NEGATIVES and AFTERIMAGES FIRE • Cells that _______ in response to a color stop firing when the color is removed • Likewise, cell that were inhibited from firing, burst forth when the color is removed

46. NEGATIVES and AFTERIMAGES • THE RESULTS? • We see red images when we blink after staring at green objects • The cells that switch on or off to signal the presence of green, send the opposite signal (red) when the green is removed…and vice versa

47. AFTER IMAGE ILLUSIONS WOO HOO!