1. PSYCHOLOGY
Vision

2. Say the color when you see it
GREEN
BLUE
ORANGE
RED

3. Try it Turn your eyes to the left Close them
Gently rub the right side of your eyelid with your finger tip
What happens?
patch of light on left moves as your finger does
Why light? Why the the left?

4. Try it explanation
Cell receptors in your eye are sensitive to pressure
Your brain interprets it as light
It interprets it as coming from the left because you activated the right side of the retina

5. Vision Transduction conversion of one form of energy to another
in sensation, transforming of stimulus energies into neural impulses

6. Vision Wavelength determines hue (color)
Intensity of color determined by amplitude (height) of wave

7. Vision Wavelength Hue Intensity
the distance from the peak of one wave to the peak of the next
Hue
dimension of color determined by wavelength of light
Intensity
amount of energy in a wave determined by amplitude
brightness
loudness

8. Vision- Physical Properties of Waves
Short wavelength=high frequency
(bluish colors, high-pitched sounds)
Long wavelength=low frequency
(reddish colors, low-pitched sounds)
Great amplitude
(bright colors, loud sounds)
Small amplitude
(dull colors, soft sounds)

9. The spectrum of electromagnetic energy

10. Vision

11. The eye
my Corny Pupil named Iris Lens me Rods & Cones - mnemonic

12. Vision - light travels….
Cornea - protects eye/bends light
Pupil which is regulated by the Iris
Dilated - interested, you like
Iris scanning for ID
Lens accommodates
Retina has the receptor cells- rods & cones

13. Retina’s Reaction to Light- Cell Receptors
Rods
peripheral retina receptors
detect black, white and gray
for peripheral or twilight conditions
Cones
receptors near center of retina
fine detail and color vision
for daylight or well-lit conditions

14. Vision- Receptors Receptors in the Human Eye Cones Rods Number
Location in
retina
Sensitivity in
dim light
Color sensitive?
Yes
Low
Center
6 million No
High
Periphery
120 million

15. Retina’s Reaction to Light
From the rods & cones chemical signals other cells are activated: (Bipolar gang of lions)
Bipolar cells
Ganglion cells
Network of ganglion cells converge to form the optic nerve
Optic nerve- nerve that carries neural impulses from the eye to the brain (thalamus to VISUAL CORTEX IN THE OCCIPITAL LOBE)

17. Pathways from the Eyes to the Visual Cortex

18. Vision problems Nearsightedness- Farsightedness- Eyeball is too long
Eyeball is too short

19. Vision p.199
Farsighted Nearsighted Normal Vision Vision Vision

20. Acuity
Nearsightedness- condition in which nearby objects are seen more clearly than distant objects because distant objects focus in front of retina
Eyeball is too long
Farsightedness- condition in which faraway objects are seen more clearly than near objects because the image of near objects is focused behind retina
Eyeball is too short

21. Vision Pupil- adjustable opening in the center of the eye
Iris- a ring of muscle that forms the colored portion of the eye around the pupil and controls the size of the pupil opening

22. Vision
Lens- transparent structure behind pupil that changes shape to focus images on the retina
Accommodation- the process by which the eye’s lens changes shape to help focus near or far objects on the retina

23. Vision
Retina- the light-sensitive inner surface of the eye, containing receptor rods and cones plus layers of neurons that begin the processing of visual information
Your brain flips objects around

24. Vision Acuity- the sharpness of vision
Can be affected by small distortions in the shape of the eye
Glasses, contacts, LASIK surgery

25. Vision
Blind Spot- point at which the optic nerve leaves the eye, creating a “blind spot” because there are no receptor cells located there p. 200 (find yours)
Fovea- central point in the retina, around which the eye’s cones cluster

26. Visual Information Processing p. 202
Feature Detectors
(Hubel & Wiesel)
nerve cells in the brain that respond to specific features
Edges, lines
Shape, angle
movement
Stimulus
Cell’s
responses

27. Feature detection
Perceptions arise from interaction of many neuron systems
Occipital lobe with the visual cortex transmits info to other lobes
Brain areas light up on fMRI scans, EEG reveal integration of activity
P. 202
Areas are specialized to do certain tasks

28. How the Brain Perceives p. 203
Bottom up & top down processing with perception
Stare at the cube, constant stimulation, change
Brain activity combines sensory input w/ assumptions and expectations

29. Illusory Contours

30. Vision
Case Studies p
Computers follow a step by step process but your brain does several things at once
What is this called?

31. Visual Information Processing p. 204-205
Parallel Processing
simultaneous processing of several aspects of a problem simultaneously

33. Parallel processing Your brain is awesome!!!!!
Read Sperry’s reflection p. 205

34. Questions If now one sees the tomato is it red? NO p. 206
Color resides in the theater of our brains.

35. Color Vision Color blind 1 in 50
Usually a male - genetic, sex-linked trait
Theories of color
Hermann von Helmholtz
Thomas Young
3 primary colors, 3 types of cell receptors

36. Visual Information Processing
Trichromatic (three color) Theory
Young and Helmholtz
three different retinal color receptors
red
green
blue

37. Color-Deficient Vision
People who suffer red-green dificiency have trouble perceiving the number within the design

38. Color Vision
Figure 12.16

39. Visual Information Processing
Opponent-Process Theory- opposing retinal processes enable color vision (HERING)
“ON” “OFF”
red green
green red
blue yellow
yellow blue
black white
white black

40. Opponent Process- Afterimage Effect

41. Visual Information Processing
Color Constancy
Perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths reflected by the object