Ch 4D depth and gestalt 1 Sensation Basic principles in perception o Absolute Threshold o Difference Threshold o Weber s Law o Sensory Adaptation Description Examples Color Perception o Trichromatic Theory o Opponent Process Theory Perception Law of compatibility Monocular Depth Perception cues o Relative size o Overlap o Linear perspective o Aerial perspective o Texture gradient o Motion parallax Gestalt Laws of Organization o Law of closure o Law of good continuation o Law of similarity o Law of proximity Perceptual Constancies o Size constancy o Shape constancy Perception Top-down processing Bottom-up processing o Description of each o Examples of each Constructive process of perception o Examples
Ch 4D depth and gestalt 2 Why is understanding the concepts from Sensation and Perception important? Egronomist, Perceptual psychologists, Engineering and Safety psychologists, educational psychologists try to make tools, mechanical devices, and learning compatible with how people think, and organize the world. What are examples where they could use their knowledge in the real-world?
Ch 4D depth and gestalt 3 Monocular cues Relative size: We assume that two objects are of similar size, we assume that the one that casts the smaller image is farther away. Overlap: If one object is partially covered, we perceive it is farther away. Aerial perspective: We perceive hazy objects as farther away than sharp, clear objects. Texture gradient: We perceive a gradual, but continuous change from a coarser, more distinct to a finer, less distinct texture element as an indication of increasing distance. Linear perspective: We interpret that apparent convergence of parallel lines as a clue to distance. Motion parallax: If you are moving, you use the speed of passing objects to estimate the distance of the objects. Nearby objects seem to zip by faster than do distant objects.
Ch 4D depth and gestalt 4 Many psychologists argue that perception, our interpretation of the world is a constructive process. There is an objective world out there, but we cannot attend or know everything about it, so we take small pieces of it and put it together to make some sort of meaning.
Ch 4D depth and gestalt 5 Gestalt Laws of Grouping and Organization There appears to be some inherent cognitive process to organize information in a simple manner. Without some sort of mental organization of the world, it can appear to be a confusing jumble. Gestalt psychologists emphasized that we perceive whole objects or figures rather than isolated bits and pieces of sensory information. There are four laws of perceptual grouping that help us organize information: Law of similarity Law of closure Law of good continuation Law of proximity
Ch 4D depth and gestalt 6 Law of Proximity Law of similarity: The tendency to perceive objects of similar size, shape or color as a unit or a figure. Law of closure: The tendency to fill in the gaps or contours in an incomplete image. Law of good continuation: The tendency to group elements that appear to follow in the same direction as a single unit or figure. Law of proximity: The tendency to view objects that are close to each other as being as a unit or a figure. Relative overlap: If two or more objects are assumed to be similar in size, the object that appears larger is perceived as being closer. Overlap: when one object partially blocks or obscures the view of another object, the partially blocked object is perceived as being farther away. Aerial perspective. Faraway objects often appear hazy or slightly blurred by the atmosphere. Texture gradient: As a surface with distinct texture gradually become less clearly defined. Linear Perspective: Parallel lines seem to meet in the distance. For example, if you stand in the middle of a railroad tracks, and look down the rails, you ll notice that the parallel rails seem to meet in the distance. Motion Parallax: When you are moving, you use the speed of passing objects to estimate the distance of the objects. Law of similarity: The tendency to perceive objects of similar size, shape or color as a unit or a figure. Law of closure: The tendency to fill in the gaps or contours in an incomplete image. Law of good continuation: The tendency to group elements that appear to follow in the same direction as a single unit or figure. Law of proximity: The tendency to view objects that are close to each other as being as a unit or a figure. Relative overlap: If two or more objects are assumed to be similar in size, the object that appears larger is perceived as being closer. Overlap: when one object partially blocks or obscures the view of another object, the partially blocked object is perceived as being farther away. Aerial perspective. Faraway objects often appear hazy or slightly blurred by the atmosphere. Texture gradient: As a surface with distinct texture gradually become less clearly defined. Linear Perspective: Parallel lines seem to meet in the distance. For example, if you stand in the middle of a railroad tracks, and look down the rails, you ll notice that the parallel rails seem to meet in the distance. Motion Parallax: When you are moving, you use the speed of passing objects to estimate the distance of the objects.
Ch 4D depth and gestalt 7 Law of Similarity You can the difference between football teams because of the law of similarity. Each team has their own color. Those on the same team are similar. (Home teams are in the lighter colors?
Ch 4D depth and gestalt 8 Perceptual constancies: Size: The perception of an object remains the same, despite its changing size on the retina. Shape: The tendency to perceive familiar objects as having a fixed shape regardless of the image they cast on our retina. Brightness: The perceived brightness of an object seems to stay the same even though the lighting conditions have changed (Hockenbury). The object is perceived to be the even when the brightness of the object changes. Size: The perception of an object remains the same, despite its changing size on the retina. Shape: The tendency to perceive familiar objects as having a fixed shape regardless of the image they cast on our retina. Brightness: The perceived brightness of an object seems to stay the same even though the lighting conditions have changed (Hockenbury). The object is perceived to be the even when the brightness of the object changes.