Powerpoint of color vision PD workshop.

1. Science of the Eye Professional Development Workshop Ishara Mills-Henry, Ph.D. MIT www.scienceoftheeye.org

8. How do we see? Indirect light

9. How big does the mirror have to be?

11. Digital Camera and the Eye

13. Label parts of the eye that are analogous to camera

15. Visible Light Spectrum Blu-Ray laser – 405 nm Standard DVD laser – 650nm Visible Light Spectrum

20. The Retina From www.howstuffworks.com

22. Photoreceptors respond to different wavelengths

23. Photoreceptors Compare the sizes of the photoreceptors outer segments, which one is bigger? Three Main Parts: a. Outer Segments b. Cell body c. Synaptic terminal Outer segments

30. Phototransduction = converting light into electrical signal Outer Segment (Rod) Na + /Ca ++ Channels

32. Activity: Central versus Peripheral Vision

36. Types of Color Blindness Monochromacy Rod or Cone – very rare, All rods or all cones are missing Dichromacy – Two types of photoreceptors are present Protanopia – red cones are missing Deuteranopia – green cones are missing Tritanopia – blue cones are missing Anomalous Trichromacy - All three photoreceptors are present but there is a spectral shift Protanomaly- spectral sensitivity of red cones are shifted Deuteranomaly – spectral sensitivity of green cones are shifted Tritanomaly – spectral sensitivity of blue cones are shifted

37. NORMAL CONE SENSITIVITY CURVES (TRICHROMAT) B R G 437 nm 564 nm 533 nm NORMAL CONE SENSITIVITY CURVES (TRICHROMAT) Activity: Color blindness

38. B R 437 nm 564 nm Deuteranopia (no green cones; only red and blue) 1% of Males

39. B G 437 nm 533 nm Protanopia (no red cones; only green and blue) 1% of Males

40. R G 564 nm 533 nm Tritanopia (no blue cones; only green and red) Very rare

41. B R 437 nm 564 nm Most common Deuteranomaly (green shifted toward red) 5% of Males G

42. Color Blindness Left Right

43. Results

44. Pedigree What is the mode of inheritance?

45. Gene Therapy for color blind monkeys All male squirrel monkeys are born only able to see mostly yellows and blues. It is difficult for them to distinguish reds from greens. Female squirrel monkeys can see the whole spectrum. What photoreceptor(s) do you think they lack? What advantage does color provide for these animals? Credit: Neitz Laboratory

51. Stare at the white cross for 30 seconds

54. More Afterimages

56. Retinal Diseases Describe how the vision of an individual with Retinitis Pigmentosa is affected? Describe how the vision of an individual with Age-related Macular Degeneration is affected?

59. Group Discussion

60. Vision and the Brain

61. Optical or Visual Illusions

62. Where’s my blind spot?

63. Why is it so hard to find? Right Eye Left Eye

64. 3-D Magic

65. Face IT!! From: http://www.youramazingbrain.org.uk/supersenses/hollow.htm

66. Other Illusions and Explanations

67. Which table is longer?

68. Rotating Wheels

69. Group Discussion

70. I hope today wasn’t like this MIT’s Stata Center It is said that MIT’s education is like drinking from a firehouse…….

72. Surveys/Feedback