Psych 421 - Sensation & Perception
Study Notes
Chapters 5-6
Rev. 9/98
Go to Chapter 6
Chapter 5 - Visual Pattern Perception
I. Theoretical Orientation
A. Data-driven (Bottom-up) Processing
B. Concept-driven (Top-down) Processing
II. Theories
A. Spatial Frequency Analysis
1. Fourier Analysis/synthesis
a) sine wave/sinusoidal grating
b) Square wave
2. Spatial Frequency & Visual Angle
3. Contrast Sensitivity Functions
a) Spatial frequency channels
4. Evidence for spatial frequency
a) selective adaptation procedure
B. Gestalt
1. Laws of Grouping
a) Law of Proximity
b) Law of Similarity
c) Law of Good Continuation
d) Law of Closure
e) Law of Common Fate
2. Law of Pragnanz
3. Figure-Ground
a) Ambiguous Figure-ground
4. Common Region
5. Uniform Connectedness
6. Phenomenological Observation and problems with the Gestalt approach
C. Computational
1. Edges to Shape Perception
a) Zero-crossing & Mexican-hat filter
b) Primal sketch
c) 2.5D sketch
d) 3-D sketch
e) Recognition-by-components using geons (Beiderman)
2. Sources of Information
a) motion
b) shading and highlights
D. Feature-Integration
1. Attention
2. Preattentive Processing - parallel processing
3. Focused Attention - serial highlighting
4. Illusory Conjunction
E. Prototype-Matching
1. What is a prototype?
2. Template-Matching
III. Role of Context on Shape Perception
A. Boundary extension
B. Letters in the context of words
1. Word-superiority effect
2. Word-apprehension effect
C. Illusory Contours
1. Inducing areas
2. Inducing lines
3. Subjective Contours
D. How can Context Distort Shape Perception
IV. Role of Time in Shape Perception - Backward Masking
V. Role of Orientation in Shape Perception
VI. Ambiguous Figures
VII. Shape Constancy - What is it, and how does it work?
A. Shape-slant invariance hypothesis
Chapter 6 - Distance & Size Perception
I. Types of Distance Perception
A. Egocentric
B. Relative
C. Depth
II. Sources of Information
A. Monocular
1. Accommodation
2. Pictorial Cues
a) Interposition
b) Size
(1) relative
(2) familiar
c) Texture Gradient
d) Linear Perspective
e) Atmospheric perspective
f) Shading
g) Height
h) Motion Parallax & Motion Perspective
i) Kinetic Depth Effect
B. Using Monocular Information to Represent 3-D Space
1. In paintings, drawings, and photographs
2. In movies
C. Binocular
1. Convergence
2. Binocular Disparity and stereopsis
a) Do horopters have a Panum's area?
b) Cross disparity
c) Uncrossed disparity
3. Physiological Basis for Stereopsis
a) Disparity-selective cells
4. Using Disparity to Create Pictorial Depth
a) Stereoscopic Picture
b) What is the correspondence problem?
c) Mystery pictures - autostereograms
5. Binocular Rivalry
III. Theories
A. Empiricism
1. Kinesthetic Information
2. Constructive theory
B. Gibsonian - direct perception
1. Ground Theory
2. Motion Perspective
3. Affordances
C. Computational - perceptual modules
IV. Experiencing a 3-D World
V. Size Perception
A. Influences on Size Perception
1. If distance to the objects is constant
a) Visual angle
b) shape
c) size of background
d) perceived velocity
e) lightness
B. Size Constancy
1. The effect of distance information
a) Holway & Boring
2. Explanations of Size Constancy
a) Size-distance invariance hypothesis
b) Unconscious inference
c) Relative-Size explanation
d) Invariants
VI. Illusions of Size and Distance
A. Muller-Lyer
B. Sander Parallelogram
C. Horizontal Vertical
D. Ponzo
E. Spacing Illusion
F. Theories
1. Theory of Misapplied Constancy
2. Incorrect Comparison Theory
3. Eye-Movement Theory
VII. Illusions of Area
1. Margin Illusion
2. Ames Room
3. Moon Illusion
a) Refraction Theory
b) Apparent-Distance Theory
c) Reference Theory
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