Perceptual Organization Module 13

Overview Perceptual Organization Form Perception Depth Perception Perceptual Constancy Module 13 01 16 15

Perception Aoccudrnig to rscheearch at Cmabrigde Uinervtisy, it deosn’t mttaer in what oredr the ltteers in a wrod are, the olny iprmoetnt tihng is that the frist and lsat ltteer be at the rghit pclae. The rset can be a toatl mses and you can still raed it wouthit porbelm. This is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe. Example of words as gestalts or wholes Module 13 01 16 15

Module 13 01 16 15

Module 13 01 16 15

Module 13 01 16 15

Module 13 01 16 15

Module 13 01 16 15

Perceptual Organization How do we form meaningful perceptions from sensory information? We organize it. Our sensations are processed according to consistent perceptual rules! Preview Question 14: What did the Gestalt psychologists contribute to our understanding of how the brain organizes sensations into perceptions? Module 13 01 16 15

Perceptual Organization: Gestalt Gestalt--an organized whole Tendency to integrate pieces of information into meaningful wholes. Gestalt psychologists showed that a figure formed a “whole” different from its surroundings. Law of Pragnanz: we perceive things in the simplest way possible a school of psychology founded in Germany in the 1900s that maintained our sensations are processed according to consistent perceptual rules that result in meaningful whole perceptions, or gestalts. 13 46. In psychology, Gestalt principles are used to explain (AP99) (A) Statistical probabilities (B) Somatic behavioral disorders (C) Perceptual organization (D) stimulus-detection thresholds (E) Altered states of consciousness 13 83. Which of the following is NOT a Gestalt principle of perceptual organization? (AP04) (A) Proximity (B) Similarity (C) Closure (D) Intensity (E) Continuity 73. The claim that a whole is different from the sum of its parts is central to which of the following schools of thought? (AP13) (A) Connectionism (B) Functionalism (C) Gestalt psychology (D) Structuralism (E) Behaviorism Module 13 01 16 15 10

Lab Characteristics of Male and Female Walks biomotion perception These labs are not strictly gestalt labs but in these activities it is clear that we attempt to interpret the stimuli as organized wholes. Lab Characteristics of Male and Female Walks biomotion perception https://www.teacherspayteachers.com/Product/Lab-Characteristics-of-Male-and-Female-Walks-biomotion-perception-1466752 Lab Identifying Male and Female walks Psychology Perception   https://www.teacherspayteachers.com/Product/Lab-Identifying-Male-and-Female-walks-Psychology-Perception-1466761 Module 13 01 16 15

Feature Pop Out The slanted line amongst vertical lines Pops Out, but the cross amongst horizontal and vertical lines does not pop out. (a) (b) Module 13 01 16 15

Figure Ground Organization of the visual field into objects (figures) that stand out from their surroundings (the background). Preview Question 15: How do the principles of figure-ground and grouping contribute to our perception of form? 43. (Graphic not included) (AP12) The reversible figure above illustrates the Gestalt organizing principle of A. proximity B. figure-ground C. closure D. common fate E. simplicity Time Savings Suggestion, © 2003 Roger Sheperd. Module 13 01 16 15

Laws of Perceptual Organization Necker cube Prince Charles/queen Elizabeth Old/young lady http://wtfoodge.com/wp-content/uploads/2009/03/optical-illusion-old-woman-young-lady.jpg Figure-Ground Animated necker cube http://dogfeathers.com/java/necker.html Module 13 01 16 15

Figure ground images Goblet or faces Module 13 01 16 15 From MIND SIGHTS by Shepard © 1990 by Roger N. Shepard. Used without permission Module 13 01 16 15

Faces or Vases? Module 13 01 16 15

Grouping We use rules to organize the figure into a meaningful form using grouping rules. (sketch these and you will not need the definitions) After distinguishing the figure from the ground, our perception needs… Module 13 01 16 15

Grouping demo http://9gag.com/gag/aOqOYv6?ref=9g.m Dead link 10/21/14 Module 13 01 16 15

Perceptual Organization: Gestalt Grouping Principles proximity--group nearby figures together similarity--group figures that are similar continuity--perceive continuous patterns closure--fill in gaps connectedness--spots, lines, and areas are seen as unit when connected 13 83. The tendency of most people to identify a three sided figure as a triangle, even when one of its sides is incomplete, is the result of a perceptual process known as (AP94) (A) Closure (B) Proximity (C) Similarity (D) Feature analysis (E) Shape constancy Have students illustrate each of these rules, a Gestalt album. Module 13 01 16 15 19

Gestalt Laws of Perceptual Organization continuity--perceive continuous patterns proximity--group nearby figures together Law of Proximity Law of Continuity Module 13 01 16 15

Laws of Perceptual Organization Law of Similarity similarity--group figures that are similar closure--fill in gaps Law of Closure Module 13 01 16 15

Law of Proximity Discovering PSY p. 106 Figure 3.14d proximity--group nearby figures together Law of Proximity Module 13 01 16 15 22

The Law of Similarity Discovering PSY p. 106 Figure 3.14a similarity--group figures that are similar The Law of Similarity Module 13 01 16 15 23

The Law of Continuity Discovering PSY p. 106 Figure 3.14c continuity--perceive continuous patterns The Law of Continuity Module 13 01 16 15 24

Perceptual Organization: Closure Gestalt grouping principles are at work here. closure--fill in gaps Module 13 01 16 15 25

Module 13 01 16 15

Reversible Dancer? Note which direction the dancer is rotating. Clockwise or counter? Link Or link http://psychology.about.com/od/sensationandperception/ig/Optical-Illusions/spinning-dancer-illusion.htm http://www.123opticalillusions.com/pages/Spinning_Dancer.php Module 13 01 16 15

Sometimes the rules don’t work…. Grouping & Reality Sometimes the rules don’t work…. Although grouping principles usually help us construct reality, they may occasionally lead us astray. Both photos by Walter Wick. Reprinted from GAMES Magazine. .© 1983 PCS Games Limited Partnership Module 13 01 16 15

Depth Perception... and the visual cliff Depth perception enables us to judge distances. Gibson and Walk (1960) suggested that human infants (crawling age) have depth perception. Preview Question 16: How do we see the world in three dimensions? Even newborn animals show depth perception. Use to test perception and acuity with infants of all sorts Each species by the time it is mobile has abilities it needs. 13 39. Eleanor Gibson and her colleagues have used the visual cliff to measure an infant's ability to perceive (AP94) (A) Patterns (B) Depth (C) Size constancy (D) Shape constancy (E) Different hues 65. Eleanor Gibson and Richard Walk used a visual cliff with a glass-covered drop-off to examine behavior in crawling infants. Even when coaxed by their mothers to crawl out onto the glass covering, most infants refused to do so, indicating that they had developed which of the following? (AP13) (A) Depth perception (B) Selective attention (C) Perceptual constancy (D) Procedural memory (E) Sensory adaptation Innervisions Visual Cliff Module 13 01 16 15

Figure 13.7 Relative size Myers: Exploring Psychology, Seventh Edition In Modules Copyright © 2008 by Worth Publishers Module 13 01 16 15

Retinal disparity: Images from the two eyes differ. Binocular Depth Cues Retinal disparity: Images from the two eyes differ. Try looking at your two index fingers when pointing them towards each other half an inch apart and about 5 inches directly in front of your eyes. You will see a “finger sausage” as shown in the inset. 13 63. A person with sight in only one eye lacks which of the following visual cues for seeing in depth? (AP94) (A) Retinal disparity (B) Linear perspective (C) Motion parallax (D) Relative size (E) Texture gradient Module 13 01 16 15

Binocular Depth Cues Convergence: A neuromuscular cue. When two eyes move inward (towards the nose) to see near objects and outward (away from the nose) to see faraway objects. OBJECTIVE 6| Describe two binocular cues for perceiving depth, and explain how they help the brain to compute distance. 13 18. Climbing an irregular set of stairs is more difficult for an individual who wears a patch over one eye primarily because (AP99) (A) Some depth perception is lost (B) Half of the visual field is missing (C) The ability to perceive interposition is lost (D) The patch disrupts the functioning of the vestibular system (E) The patch alters the ability of the open eye to compensate Module 13 01 16 15 32

Why doesn’t Leela have binocular depth cues? Ever watch Futurama? Why doesn’t Leela have binocular depth cues? Module 13 01 16 15

How about a BB gun accident? Module 13 01 16 15

Monocular Depth Cues Relative Size: If two objects are similar in size, we perceive the one that casts a smaller retinal image to be farther away. Monocular cues are available to each eye individually Module 13 01 16 15

Monocular Depth Cues - Relative Size Relative Size: If two objects are similar in size, we perceive the one that casts a smaller retinal image to be farther away. Module 13 01 16 15 36

Monocular Depth Cues Interposition: Objects that block other objects tend to be perceived as closer. Occlude Rene Magritte, The Blank Signature, oil on canvas, National Gallery of Art, Washington. Collection of Mr. and Mrs. Paul Mellon. Photo by Richard Carafelli. Module 13 01 16 15

Interposition Interposition: Objects that occlude (block) other objects tend to be perceived as closer. Which horse is closer Module 13 01 16 15

Monocular Depth Cues Relative Height: We perceive objects that are higher in our field of vision to be farther away than those that are lower. This demo does not work, I used to have an animation here they are the same size when next to each other but the size actually changes as it rotates….I think it is a scaling issue. Module 13 01 16 15

http://wnetoa.soup.io/tag/Relative%20Sizes?since=113148519 Module 13 01 16 15

Tall Arch In this picture, the vertical dimension of the arch looks longer than the horizontal dimension. However, both are equal. Relative Height: We perceive objects that are higher in our field of vision to be farther away than those that are lower. Rick Friedman/ Black Star Module 13 01 16 15 41

Monocular Depth Cues Relative motion: Objects closer to a fixation point move faster and in opposing direction to those objects that are farther away from a fixation point, moving slower and in the same direction. Module 13 01 16 15

Motion Perception Motion Perception: Objects traveling towards us grow in size and those moving away shrink in size. The same is true when the observer moves to or from an object. OBJECTIVE 8| State the basic assumption we make in our perceptions of motion, and explain how these perceptions can be deceiving. Module 13 01 16 15 43

Apparent Motion Phi Phenomenon: When lights flash at a certain speed they tend to present illusions of motion. Neon signs use this principle to create motion perception. One light jumping from one point to another: Illusion of motion. Two lights flashing one after the other. Module 13 01 16 15 44

Monocular Cues Linear Perspective: Parallel lines, appear to converge in the distance. The more the lines converge, the greater their perceived distance. 6. Which monocular depth cue is illustrated in the figure above? (AP13) (A) Accommodation (B) Texture gradient (C) Relative size (D) Interposition (E) Linear perspective © The New Yorker Collection, 2002, Jack Ziegler from cartoonbank.com. All rights reserved. Module 13 01 16 15

Perceptual Organization: Linear Perspective Module 13 01 16 15 46

Discovering PSY p. 109 Photo Linear Perspective Module 13 01 16 15 47

Interposition, relative size, linear perspective Module 13 01 16 15

Monocular Cues Light and Shadow: Nearby objects reflect more light into our eyes than more distant objects. Given two identical objects, the dimmer one appears to be farther away. From “Perceiving Shape From Shading” by Vilayaur S. Ramachandran. © 1988 by Scientific American, Inc. All rights reserved. Module 13 01 16 15

In or Out? Light and Shadow: Nearby objects reflect more light into our eyes than more distant objects. Given two identical objects, the dimmer one appears to be farther away. Module 13 01 16 15

Monocular Cues Texture Gradient: Indistinct (fine) texture signals an increasing distance. Module 13 01 16 15 51

Perceptual Constancy Preview Question 17: How do perceptual constancies help us to organize our sensations into meaningful perceptions? Example pg 181 AP 43 Yr old who gained sight at 40 lacked perceptual constancy,…people walking away appeared to be shrinking. (Bower 2003) 28. As you watch a friend walk away from you, your retinal image of your friend gets smaller. Despite this, you do not perceive him to be shrinking. This is an example of (AP12) A. a motion parallax B. retinal disparity C. size constancy D. continuity E. common fate 17. In visual perception, size constancy occurs as an object comes closer to the viewer because the(AP13) (A) image on the retina becomes smaller (B) image on the retina remains constant in size (C) perceived distance of the object becomes greater (D) perceived distance of the object becomes smaller (E) perceived distance of the object remains constant Perceiving objects as unchanging even as illumination and retinal images change. Module 13 01 16 15

We still perceive the door as rectangular Figure 13.10 Shape constancy Myers: Exploring Psychology, Seventh Edition In Modules Copyright © 2008 by Worth Publishers Module 13 01 16 15

Shepard’s tables (Roger Shepard) Link http://www.youtube.com/watch?v=PhRbsaSMMVU Link Figure 13.9 Perceiving shape Myers: Exploring Psychology, Seventh Edition In Modules Copyright © 2008 by Worth Publishers Module 13 01 16 15

Color Constancy Perceiving familiar objects as having consistent color even when changing illumination filters the light reflected by the object. Our perception of color guided not only by reflected light but by surrounding objects too. Link http://www.youtube.com/watch?v=TVUrHf2kcUM Link Color Constancy Module 13 01 16 15

Moon Illusion The moon just above the horizon typically appears to be unusually large because we perceive it as unusually far away from ourselves. This illustrates the importance of context effects. This is a result of distance cues, which make the horizon moon seem farther away. The horizon moon appears to shrink in size if it is viewed through a narrow tube that eliminates the perception of distance cues. Moon appears up to 50% larger at the horizon Module 13 01 16 15

Size-Distance Relationship The distant monster (below, left) and the top red bar (below, right) appear bigger because of distance cues. Right – Ponzo illusion Same size retinal images but linear perception cues tell us the only way a far object can cast same size retinal image is if it is larger Alan Choisnet/ The Image Bank From Shepard, 1990 Module 13 01 16 15

Ponzo Illusion Converging lines indicate that top line is farther away than bottom line Hockenbury powerpoint (Schulman) Module 13 01 16 15 58

Visual Illusions The Ponzo Illusion The Müller - Lyer Illusion Which line appears longer? Most think the top line is longer. The lines are of equal length. The Müller - Lyer Illusion Module 13 01 16 15

http://faculty.washington.edu/somurray/sizedemo.jpg Demo from his site… http://vision.psych.umn.edu/users/boyaci/Vision/SizeAppletLarge.html Hussein Boyaci [will] be the same.” But would they? “I had that phrase in my talk, but we didn't really know that they would be the same size in VI, so I thought I should go back and test that before I said it.” That's what Murray did. His breakthrough experiment was supposed to be nothing more than a control experiment—one meant to verify what vision researchers already knew. Here's what Murray did. He captured fMRI scans of the brains of human volunteers as they viewed the two images (among others) above (Figure 1). In the picture without a background, it's obvious that the two balls are the same size, and Murray's research subjects reported seeing them that way. Their self-reports were confirmed in scans of the VI. The two balls occupied the same amount of neural space—spots that the MRI detects as increased brain activity in a particular area. The images of the balls produced a “retinotopic image,” an exact duplicate of the information sent from the retina to the VI. Where conventional wisdom failed was in predicting the VI map of the balls in the brick hallway image. What Murray expected was the same result as with the no-background balls. The VI should have received and recorded what the retina “saw.” But it did not. The volunteers reported that the ball in the back was at least 17 percent larger than the one in the front. The scans of their Vi's showed that, too. The regions of activation were 17 percent larger, just as when the people viewed balls that actually were bigger. The illusion produced differences inVI activity just as a real size differences did.2 What is revolutionary about Murray's results? No one expected size judgments to be made in (or even before) the VI.   From Brain Sense: The Science of the Senses and How We Process the World Around Us by Faith Hickman Brynie Module 13 01 16 15

Do relative size lab http://www.teacherspayteachers.com/Product/Lab-Visual-Cues-and-Object-Size-Perception-Vision-Psychology-1474027 Module 13 01 16 15

Figure 5.2: Misperceiving Reality: Which Line Is Longer? From Perplexing Puzzles and Tantalizing Teasers, (p.75), by Martin Gardner, 1988, New York Dover. Module 13 01 16 15

Size-Distance Relationship Both girls in the room are of similar height. However, we perceive them to be of different heights as they stand in the two corners of the room. Ames room Both photos from S. Schwartzenberg/ The Exploratorium Module 13 01 16 15

Ames Room Works only when viewed from one angle Video: Discovering Psychology, Updated Edition: Sensation and Perception (Annenberg/CPB Project, 30 minutes) This program provides an excellent complement to text coverage. After identifying the important structures involved in visual sensation, the program describes how visual information is processed. Nobelist David Hubel, whose work with Torsten Wiesel on feature detectors is described in the text, is interviewed. The program portrays perception as involving an active construction of reality. It reviews the basic principles of perceptual organization and interpretation, paying special attention to the role of expectancy and context effects. A staged bank robbery makes viewers aware of both the complexity of the perceptual process and of human susceptibility to error. The program includes vivid demonstrations of several phenomena described in Modules 13 and 14, including the Ames room, impossible figures, ambiguous figures (saxophonist vs. woman’s face), and perceptual adaptation to disorienting glasses. The Ames room is designed to demonstrate the size-distance illusion. Ramachandran explains the Ames room http://www.youtube.com/watch?v=Ttd0YjXF0no Module 13 01 16 15

The color and brightness of square A and B are the same. Lightness Constancy Also called brightness constancy Our brain calculates brightness based on surrounding objects – Relative luminance …squares labeled A and B, and make a circular hole just a bit smaller than the checkerboard square on which each sits. When you look only through the holes and without the rest of the image, you will see that they are indeed identical in color. Again the culprit is an unconscious inference, a mindbug that automatically goes to work on the image. What causes this remarkable failure of perception? Several features of this checkerboard image are involved, but let us attend to the most obvious ones. First of all, notice that B is surrounded by several dark squares that make it look lighter than it is, merely by contrast; likewise, just the opposite, A is surrounded by adjacent lighter squares that make it seem darker than it actually is. Second, notice the shadow being cast by the cylinder. This darkens the squares within the shadow including the one marked but the mind automatically undoes this darkening to correct for the shadow, lightening our conscious experience of B. As with the table illusion, the mechanisms that produce this one also exist to enable us to see and understand the world successfully. Ted Adelson, a vision scientist at MIT and creator of this checker shadow image, writes: "As with many so-called illusions, this effect really demonstrates the success rather than the failure of the visual system. The visual system is not very good at being a physical light meter, but that is not its purpose."5 Such examples force us to ask a more general question: To what extent do our minds possess efficient and accurate methods that fail us so miserably when we put them to use in a slightly revised context?   Blindspot: Hidden Biases of Good People by Mahzarin R. Banaji & Anthony G. Greenwald Courtesy Edward Adelson The color and brightness of square A and B are the same. Module 13 01 16 15

Module 13 01 16 15

Module 13 01 16 15