Major+Objections


 * The Theory of Direct Realism **

This theory states that we are directly aware of the objects around us. A direct realist will believe that the world is the way we perceive it is, and we perceive it as this because this is the way the world is. It is also known as naïve realism or the common sense theory. For example, if I have an experience as of a large apple tree, then that’s because there’s a large apple tree in front of me. If the apples on the tree appear to me to be red, then that’s because there are objects in front of me, apples, that have the property redness; simple ("Theory of knowledge,"2012).



** Recognition-by-Components Theory **

Recognition-by-Component (RBC) theory, proposed by Irving Biederman, states that we recognize objects based on basic units of objects, called geons. Biederman’s theory proposed 36 geons, which allow us to mentally represent a majority of the objects we can identify easily. Although this theory can explain many observations for shape-based object perception, “our vision is far too complex to be determined by a few geons (Goldstein, 2010)”. For example, we may see two dogs with the same shape and distinguish between them on the basis of their texture or markings on their fur. There are also certain things in the environment that are tough to create using geons, like clouds (Goldstein, 20 10).

** Binocular Rivalry **

Binocular rivalry is a phenomenon which states that if an image is presented to the right eye and another image is presented to the left eye, perception will not happen simultaneously, but will alternate between the two eyes (Goldstein, 2010). Wheatstone was able to prove that both the left and right eye could simultaneously fuse images into a solid, three- dimensional pattern of the world due to his invention of the stereoscope (Blake, 2002). A stereoscope is made up of two similar images next to one another along with a set of lenses to view the images. When one views the images through the lenses, the set of two-dimensional images fuse together into a solitary three-dimensional picture.

Stereoscope

** Theory of Unconscious Inference **

Hermann von Helmholtz proposed the theory of unconscious inference, which proclaimed that incoming sensory data is translated by prior experiences. This is done quickly and unconsciously. In other words, one would infer Figure 1 is a cube covering six circles due to past experiences with similar circumstances. One of Helmholtz’s most important studies, which support his theory, included the use of optical prisms. When worn over the eyes, the visual field is laterally shifted, so when a subject reaches for an object they will miss it. Over time, they will adapt to the prisms and reach accurately. This portrays that our perception can chance through experiences. Once the subject is fully adapted to the glasses they are asked to remove them and point to an object. The result is the subject making an error in the opposite direction. This is due to the idea that prior experience solely influences this positioning (McConnell, 2010).
 * [[image:http://www.owlnet.rice.edu/%7Epsyc351/Images/subjectiveneckercube.jpg width="344" height="339" align="center" caption="Figure 1"]] ||
 * Figure 1 ||

** Ecological Approach **

James J. Gibson suggested that the retinal image was not the basis of vision, but rather something he called the optic array, which is the structure created by textures, surfaces, and contours of the environment. This is referred to as the ecological approach and focuses on environmental information. As you move, one of the sources of the information of perception is optic flow. Optic flow is referred to as the flow of elements in a scene relative to a viewer. It provides constant information because it occurs as long as the observer is moving (Goldstein, 2010). Gibson also argued for a perception-action approach (McConnell, 2010), also known as self-produced information (Goldstein, 2010), meaning action requires perception, and perception requires action (McConnell, 2010). Another type of information specified by Gibson are affordances, which indicate what an object is used for. Studies have been done with people who have damage to their temporal lobe that impairs their ability to name objects. The patient given a cue, either the name of the object or what the object’s function was. The results indicated that the patient identified the objects more quickly and accurately when given the objects function. The scientists concluded that the patient was utilizing his knowledge of the object’s affordances to help find it (Goldstein, 2010). Optical Flow

** Gestalt Approach **

Gestalt psychology is based on the belief that the whole is greater than the sum of its parts, meaning that perception is not just adding up one’s sensations. Marx Wertheimer recruited Wolfgang Kohler and Kurt Koffka to participate in his experiment of the phi phenomenon using a tachistoscope, a device he used to present stimuli to the eye in either brief intervals, or very rapid succession. In his experiments, Wertheimer would present a vertical line on the left-hand side of the screen to the participant, it would disappear, and then reappear on the right side. When timing was slow, the observer saw two separate lines. When timing was very rapid, they saw two lines, but at the same time. When the rate of timing was moderate, the participant observed seeing only one line, moving from left to right and back to the left again (McConnell, 2010). This is idea of apparent movement, where two stimuli are slightly positioned differently and are then flashed one after the other. Movement is then perceived between the two stimuli (Goldstein, 2010). This supported Wertheimer’s hypothesis that perception is not just the sum of the parts. Wertheimer, Koffka, and Kohler adopted the name gestalt because it means pattern or form, showing that during perception the mind is actively looking for and generating patterns (McConnell, 2010). There are six laws of organization that the mind utilized to identify patterns, according to the Gestalt theory. The law of pragnaz states that every stimulus pattern is viewed in the simplest way possible. For example, the Olympic symbol is seen as five circles, not as nine shapes. The law of similarity illustrates similar objects appear to be grouped together. The law of good continuation explains when straight or smoothly curving lines belong together, they are seen as connected, and these lines are seen to follow the smoothest path. The law of proximity states objects which are near one another appear to be grouped together. According to the law of common fate, objects that are moving in the same direction are seen to be grouped together. The law of familiarity, objects which form patterns that seem to be meaningful or familiar are grouped together. The mind uses these laws to create perceptional patterns from the environment (Goldstein, 2010).

Law of Pragnanz

Law of Similarity



Law of Good Continuation

Law of Proximity

Law of Common Fate