Perception:

1. Perception: Organization and Interpretation

2. Perception is… • Our way of selecting, organizing, and interpreting our sensations. • Perception blends with Sensation into one continuous process to help us represent the world in our heads.

3. Perceptual Organization • Gestalt • We organize our sensations into a whole rather than see it parts. • Necker Cube • Types of Perceptions: form, depth, motion, constancy.

4. Seeing things as wholes Aoccdrnig to rscheearch at an Elingsh uinervtisy, it deosn't mttaer in waht oredr the ltteers in a wrod are, olny taht the frist and lsat ltteres are at the rghit pcleas. The rset can be a toatl mses and you can sitll raed it wouthit a porbelm. Tihs is bcuseae we do not raed ervey lteter by ilstef, but the wrod as a wlohe.

5. Necker Cube A simple 3D figure, but a complex arrangement of lines in 2D. The 3D interpretation prevails in perceptual organization.

6. Form • Figure and ground • Grouping

7. Form: Figure and Ground • Reversible, always organize the stimulus into a figure seen against a ground. • Figure - the object of interest • Ground - the background

8. Form: Grouping • The perceived whole is different from it parts. • Helps us to construct a reality. • Factors that come into play when grouping: • Closeness (_____________________) • Sameness (_____________________) • Ongoing (_______________________) • Linked (_________________________) • Complete (______________________)

9. Perceptual Organization: Form: Grouping Principles

10. Depth Perception • Two dimensional images are projected onto the retina. • DP is our ability to see things is three dimensions using depth cues: • Binocular cues • Monocular cues

11. Depth Perception:Binocular Clues • Eyes are ~2 1/2 inches apart. • Our eyes get different images of the world. • The larger the angle, the nearer the object. • See next slide • Convergence • Retinal Disparity

13. Depth Perception:Monocular Cues • We rely on these to gauge depth and distance. • Relative size • Interposition • Relative Clarity • Texture Gradient • Relative height • Relative motion • Linear perspective • Lights and shadows • Find an example of one of these now….. • Page 235 in textbook

14. Motion • Stroboscopic motion • Phi phenomenon • Motion after effect

15. Perceptual Constancy • Enables us to perceive an object as unchanging regardless of changes in the stimulus we receive. • Impt examples: Muller-Lyer; Ponzo

16. Muller-Lyer Illusion • The top horizontal line looks longer because it also looks farther away. • The inward pointing arrows signify that the horizontal line is closest to you, and the outward pointing arrows signify the opposite case.

17. Ponzo Illusion • Converging lines indicate that top line is farther away than bottom line

18. What effects our perceptions? • Deprivation • Adaptation • Set • Context • 10-11 exercise • Sine wave Speech

19. Describe this picture…

20. Fraser Spiral • http://www.michaelbach.de/ot/ang_fraser/index.html

21. Deprivation • Critical period- that optimal time period after birth when certain events must take place for normal development. • Use it “soon” or lose it. • Cat example

23. Adaptation • We can become “biperceptual” • Bilinguals- can switch back to native/new language at will. • Adaptation is difficult at first, but can happen with no apparent recourse for previous perceptions.

24. Perceptual Set • A mental predisposition that influences what we perceive. • Influences include schemas, past experiences, stereotypes. • Context • Top-down influences our bottom-up.

25. Perceptual Set • Call out the number that follows each of these…. • Pronounce the words that I am about to spell • Provide punctuation to make these words meaningful. • The telephone game. • Just for fun