Perceptual Constancies

PERCEPTUAL CONSTANCIES

Lets us "look" past most unimportant changes of the constant unchanging aspects of most objects of events, making our perceptions stable. It's critical to everyday life, without it we would not be able to recognize someone or something in different levels of lighting, color, size, shape or subtle changes. Thanks to this it makes life more simple to do everyday tasks.

SIZE CONSTANCY

Allows us to judge an object's apparent size from any distance. When the distance of an object increases the size of your retinal image changes too. We know that if a car is far away it looks small but it still maintains its same shape as it is if we were close to it. This varies with distance. Objects maintain same size regardless of how smaller or different it looks from far away it appears to us. 

Notice how objects that are smaller is far away and seems small
we get that it's just as same as people in front of painting

SHAPE CONSTANCY

Shape of objects seem unchanged even though they're viewed from different angles.. An object's shape changes in different angles, this is the stability of a shape despite changes in image shape. They are important because they allow us to perceive simple unchanging nature of objects and things in life we see around us. Without this, objects would appear to be changing depending on light, distances and different angles and viewpoints. But since we do have it, it makes the world we see more secure stable and we can predict it and lets us do everyday things we have to do without struggle and confusion.

 life without shape constancy

street looks like there's a river, at angle flat we
know it's just a art drawing on the street.

BRIGHTNESS CONSTANCY

Important in stabilizing perception. Visual objects perceived as having the same brightness under different levels of illumination. 

Different times throughout the day affect lighting of everyday objects, still understand objects remain

Law of Proximity: States that objects that are near or proximate, to each other tend to be grouped together. This law is a part of the Gestalt Laws of Perceptual organization and also gestalt psychology founded by Max Wertheimer. Movies or motion pictures are two examples of the law of proximity, because movies are just a rapid succession of still images that create a seamless visual experience. According to the laws of proximity, things that are near each other tend to be grouped together.

Law of Figure-Ground Perception: Used to describe the tendency of the visual system to simplify a scene into the main object  that we are looking at (figure) and everything else that forms the background (ground). This law is often illustrated with the "faces or vases" illusion, also known as Rubin Vase. This depends on what you see as the black or white figure, you can either see two faces (black) in profile or a vase in the center (white). The flag of Canada can also be seen as Figure-Ground Perception, because the flags background edges of the maple leaf can can also be seen as two faces arguing. 

Binocular Cue: Us as humans are able to see things that are both far and near, and we can actually identify where these things are in space. This is a sort of depth perception that requires both of our eyes, also known as binocular cues. The first example of this theory; if you hold one finger about six inches away from your eyes and look at it, then move it a foot farther. You will actually be able to feel the change in eye muscles at different distances. Another example of Binocular cues is the "visual cliff" experiment that was used on infants. 

http://education-portal.com/academy/lesson/law-of-proximity-examples-lesson-quiz.html#lesson

http://en.wikipedia.org/wiki/Figure–ground_(perception) 

http://moodle.sbc.ac.uk/sharedContent/repository/psychology/Level_3/act_PK1_Pictorial%20perception%20and%20depth%20cues/s04binocular_cues/010a_binocular.htm

2 Monocular Cues and Motion Perception

Monocular Cues

7) Interposition: Interposition is a monocular cue that occurs when objects overlap.  The object being overlapped is considered to be further away, while the object blocking part of the other object is perceived as closer.
Examples: https://www.youtube.com/watch?v=jXx_duoC1oM

In this picture the king of clubs is obscuring our view of the king of spades, so we then perceive the king of clubs as closer .

8) Relative Motion (Motion Parallax):  Relative Motion is a monocular cue that explains that stable objects may appear to move when we are moving.  When you focus on an object, anything in front of that object will appear to move faster backwards, and anything behind the fixation point will move with you.  

Examples:  If you are flying in a plane and focus on a baseball diamond, then anything between the plans and the baseball diamond will appear to move backwards, while anything behind the diamond will appear to move with the plane. 

9) Motion Perception

Our brain perceives that an object that is shrinking is also retreating.  For example, when you are backing out of your driveway your house appears to be shrinking.  That is how we know that we are in fact reversing out of the driveway instead of staying still.  Our brain also perceives enlarging objects as objects that are coming closer.  For example, the car in front of you appears to be getting bigger the closer you get to it.  This lets us know that we are approaching the car in front.  When someone tries to catch a flying object they will look at the ball from a certain angle and try to collide with the objects projected motion path.  Stroboscopic movement explains how the brain interprets still different images as one continuous motion i.e. a movie.  The phi phenomenon is when two still lights alternatively flash off and on giving the image of a light moving back and forth.  For example, certain cars have blinkers that will have the light split up into three separate sections, and when you turn on the blinker, the lights will each flash one at a time starting with the inner light working outwards.  This gives the person behind them the view of a rectangular normal blinker.

Rules of Perceptual Organization

Rules of Perceptual Organization

Closure- We fill in gaps to create a complete, whole object. Usually the grouping principle help us construct reality. Sometimes they lead us astray as with other perception. 

Example: This picture represents closure because when we look at the gems on the pointe shoes we see an assortment of gems. Some of the gems in a circle the others randomly above it, but when you imagine connecting the lines up top you see the letter W.

Continuity- We perceive smooth, continuous patterns rather than smooth, discontinuous ones. Rather than seeing separate lines and angles, lines are seen as belonging together.

Example: This is a window on a door in my house. It represents continuity because the grates within the windows are two vertical lines and two shorter horizontal lines but when we look at it we see one unit being smooth and together.

Similarity-  We group together figures that are similar to each other. 

        Example: This is a picture of a basket in my house. When we look at the circles we see one images not separate circles. The circles within the basket connect and we don't process it as separate little circles we perceive it as one design going together.