- Slides: 27
Introduction to Perception: Visual Perception
Aim: When we look at the world, why does it seem stable or constant? Do Now: Describe this image.
Perception: The process of assembling and organizing sensory information to make it meaningful.
Illusions: Inaccurate perceptions
Definitions Distal stimulus: The actual stimulus (e. g. , object, sound) that exists in the environment Proximal stimulus: The information that registers on your sensory receptors (e. g, the image of the object on your retina) Iconic memory: Visual sensory memory that allows a proximal stimulus to persist for 200400 ms. after the stimulus has disappeared
Why does line (a) in the Muller-Lyer illusion look longer than line (b)?
Gestalt: An organized whole, shape or form. Similarity: A perceptual cue that involves grouping like things together. Proximity: A perceptual cure that involves grouping that are near one another.
Closure: The process of filling in the missing details of what is viewed.
Illusory Contour Illusion n We see contours even when they are not present in the stimulus n Some cells in our visual respond to the contours formed by the triangles n The visual system unifies the stimuli into the perception of a square
Monster Size Illusion n The upper right creature looks larger than the lower left If you measure them, they are the same size Depth perception: cues in the background, such as converging lines, contribute to a perception of distance This is a constructive activity of your brain.
The Visual Cliff: Used to demonstrate depth perception
Figure Ground (Ambiguous Figure) Illusion n Figure = distinct shape with clear edges n Ground = left over region n Figure seems closer to us and more dominant n In ambiguous figures, figure and ground reverse, because we can recognize both representations
Old Woman/Young Woman Face perception n Why study face recognition? n Agnosia is an impairment in visual object recognition. Proposagnosia is an impairment in visually recognizing faces. Visual agnosia is an inability to recognize visual objects that is neither a function or general intellectual loss nor a loss of basic sensory abilities n n
How do we assign meaning to stimuli? F Letters Objects Faces
Inattentional Blindness Also known as "perceptual blindness" which is the phenomenon of not being able to see things that are actually there. This can be a result of having no internal frame of reference to perceive the unseen objects, or it can be the result of the mental focus or attention which cause mental distractions. The phenomenon is due to how our minds see and process information.