Perception

1
Perception

• Selective Attention
• Focus of conscious awareness on a particular
  stimulus

2
Perception

• Selective Attention
• Perceptual Illusions
• Bottom-Up Processing
• Top-Down Processing

3
Perceptual Illusions
4
Perceptual Organization- Gestalt

• Visual Capture
• Tendency for vision to dominate the other senses.
• Grouping
• The perceptual tendency to organize stimuli into
  coherent groups.

5
Perception of Form

• Gestalt- an organized whole
• tendency to integrate pieces of information into
  meaningful wholes
• Gestalt rules of grouping
• Proximity group nearby figures together
• Similarity group figures that are similar
• Closure fill in gaps
• Continuity perceive continuous patterns
• Connectedness spots, lines and areas are seen as
  unit when connected

6
Perceptual Organization- Grouping Principles
7
Perceptual Organization

• Figure and Ground organization of the visual
  field into objects (figures) that stand out from
  their surroundings (ground)

8
Depth Perception

• Depth Perception
• ability to see objects in three dimensions
• allows us to judge distance
• Binocular cues
• retinal disparity
• convergence

9
Depth Perception

• Monocular cues
• relative size
• smaller image is more distant
• interposition
• closer object blocks distant object
• relative clarity
• hazy object seen as more distant
• texture coarse --gt close fine --gt distant

10
Perceptual Organization-Depth Perception
Relative Size
11
Perceptual Organization-Depth Perception
12
Depth Perception

• Monocular Cues (cont.)
• relative height
• higher objects seen as more distant
• relative motion
• closer objects seem to move faster
• linear perspective
• parallel lines converge with distance
• relative brightness
• closer objects appear brighter

13
Perceptual Organization-Depth Perception
Perspective Techniques
14
Perceptual Organization
15
Motion Perception

• Real motion
• Apparent motion
• stroboscopic motion
• phi phenomenon

16
Perceptual Constancy

• Perceptual Constancy
• perceiving objects as unchanging despite changes
  in retinal image
• color
• shape
• size

17
Sensory Restriction-Blakemore Cooper, 1970

• Kittens raised without exposure to horizontal
  lines later had difficulty perceiving horizontal
  bars.

18
Perceptual Interpretation

• Perceptual Adaptation
• (vision) ability to adjust to an artificially
  displaced visual field
• prism glasses
• Perceptual Set
• a mental predisposition to perceive one thing and
  not another

19
Perceptual Set- Schemas

• What you see in the center is influenced
  by perceptual set