1. Sensation and Perception

2. Sensation and Perception
Sensation: stimulation of sense organs
Perception: selection, organization, and interpretation of sensory input
Five senses:
Vision
Hearing
Touch
Taste
Smell

3. We do not view the world as it is, but instead actively construct a
perception of it,

4. Vision - components Cornea: where light enters the eye
Lens: focuses the light rays on the retina
Iris: colored ring of muscle, constricts or dilates via amount of light
Pupil: regulates amount of light
Cones: adapted for color vision, daytime light, and detailed vision
Rods: adapted for vision in dim light

5. Vision - color

6. Vision - color A replica of the Ishihara test for color blindness.
Figure 4.12
A replica of the Ishihara test for color blindness.

7. Vision - color
Figure 4.9
Negative afterimages. Stare at the dot near the middle of the flag for at least 30 seconds. Then look immediately at a plain sheet of white paper or a white wall. You will see the American flag in red, white, and blue. Reduced sensitivity to green, black, and yellow in the visual system, caused by prolonged staring, produces the complementary colors.

8. Vision - color
Brightness Constancy. The orange squares within the blue squares are the same hue, yet the orange within the dark blue square is perceived as brighter. Why?

9. Vision - Acuity

10. Vision – Gestalt principles

11. Vision – Reversible Figures

12. Vision – Perceptual Set

13. Vision – Subjective Contours

14. Vision – Subjective Contours

15. Vision – Distal and Proximal Stimuli

16. Vision – Perceptual illusions

17. Vision – Perceptual illusions

18. Vision – Size and Distance
The trade-off between size and distance: A given image on the retina can indicate either a small, close object or a large, distant object.

19. Vision – Attention
One of the drawings used by Mackworth and Loftus (1978) to investigate attention. Observers attend to unexpected objects longer than they do to expected objects. In this drawing, observers looked longer at the octopus than they did at a tractor placed in the same spot. What do you think would happen if a tractor were shown upside down or on the roof of the barn?

20. Vision – Depth

21. Vision - Depth

22. Vision - Movement

23. More examples on the internet…
Left-handed v. Right-handed quiz
Illusions - many examples
I still can’t figure this out!

24. (2) Hearing - components

25. Hearing – source and loudness

26. (3) Touch - Components

27. Figure 4.49 The tongue and taste
(4) Taste - Components
Figure The tongue and taste

28. (5) Smell - Components