VIEWS: 22 PAGES: 23 POSTED ON: 11/19/2012
Perception and Illusion Module Nine Learning Objectives How does sensation differ from perception? What are the processes involved in depth perception? Why are we tricked by visual illusions? Difference between sensation and perception Sensation – The stimulation of the sense receptors Perception – The organization and interpretation of sensory stimulation – Despite an inverted retinal image, we don’t perceive flipped images – Behavior affected by experience and learning – People’s expectations influence what they see Gestalt psychology – The whole (perception) is greater than the sum of its parts (sensation) Gestalt Principles of Grouping Proximity – Seeing rows rather than columns – We perceive things that are close to be a single unit Continuity – Seeing lines that connect 1 to 2 and 3 to 4 in C – Viewers tend to see elements in ways that produce smooth continuation Gestalt Principles of Grouping Similarity – Seeing columns of orange and red dots – Objects sharing features are grouped together Closure – Seeing a horse in D – Viewers tend to supply missing elements to close figure Closure Context Effects How we see the middle character, depends on whether we examine the rows or the columns Context Effects How we perceive color is dependent upon nearby colors. The pinks are the same shade Op art from the 70s capitalized on this and other perceptual illusions Depth and Distance Perception Binocular cues depend on input from both eyes – Retinal disparity Each eye has a slightly different view decreases with distance – Convergence eyes moving closer together as object draws near Depth and Distance Perception Monocular cues depend on input from only one eye – Relative image size (smaller objects are father away) – Pictorial depth cues (linear perspective) – Interposition Closer objects will block view of more distant objects Muller-Lyer Illusion Muller-Lyer Illusion Ponzo Illusion The retinal images of the red lines are equal! Depth cues trick us into perceiving the upper line as more distant Because of size constancy, an object that is farther away but casts same retinal image must be larger Optical illusions Show how perceptual organization can fool us We use perceptual hypotheses to organize our sensory experiences Sometimes, as is the case in optical illusions, our hypotheses our wrong
"Sensation and Perception"