1. Vision

2. Transduction
Conversion of sights, sounds, smells into neural impulses our brain can interpret

3. Wavelength (Hue)
Hue (color) is the dimension of color determined by the wavelength of the light.

4. Different wavelengths of light result
Wavelength (Hue)
Violet
Indigo
Blue
Green
Yellow
Orange
Red
400 nm
700 nm
Short wavelengths
Long wavelengths
Different wavelengths of light result
in different colors.

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

6. OBJECTIVE 5| Describe the major structure of the eye, and explain how they guide the incoming ray of light toward the eye’s receptor cells.

7. 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.

8. Test your Blind Spot
Use your textbook. Close your left eye, and fixate your right eye on the black dot. Move the page towards your eye and away from your eye. At some point the car on the right will disappear due to a blind spot.

9. Feature Detector
*Nerve cells in the brain that respond to specific features (shapes, angles, movement)
*Specific combinations of temporal lobe activity occur as people look at shoes, faces, chairs and houses.

10. Visual Information 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.
OBJECTIVE 8| Discuss parallel processing and discuss its role in visual processing.

11. Color Vision
We can discriminate between some 7 million different color variations
Young-Helmholtz - Trichromatic Theory
The retina has three types of color receptors
Red, green, or blue
When we stimulate combinations of these cones, we see other colors

12. Color “Deficient” not Color Blind
Genetic disorder in which people are blind to green or red colors.
Lack red or green sensitive cones
Ishihara Test

13. Opponent Colors Theory: opposing retinal processes enable color vision
-Red/Green, Yellow/Blue, White/Black
Gaze at the middle of the flag for about 30
Seconds. When it disappears, stare at the dot and report
whether or not you see Britain's flag.

14. Opponent Process Theory
Hering proposed that we process four primary colors combined in pairs of red-green, blue-yellow, and black-white.
Cones
Retinal
Ganglion
Cells

15. Color Constancy
Color of an object remains the same under different illuminations.
However, when context changes the color of an object may look different.
OBJECTIVE 10| Explain the importance of color constancy.
R. Beau Lotto at University College, London

16. Visual Information Processing
What part of the brain processes visual info?
Optic Nerve  Thalamus  Visual Cortex
OBJECTIVE 7| Discuss the different levels of processing that occur as information travels from the retina to the brain’s cortex.

17. Review
1. What is the process of converting energies into impulses our brains can interpret?
2. What part of the light wave determines color?
3. What part of the light wave determines brightness?
4. What is the muscle in your eye that is colored?
5. What is the opening in your eye called?
6. Where are all the rods and cones located?
7. What changes shape to help focus images?
8. What part of the eye allows you to see color?
9. What is it called when we can process various things at once about a visual stimuli?