Transaction Management in Database Management System
Perception
1. PERCEPTION process by which organisms interpret and organize sensation to produce a meaningful experience of the world
2. Principles Of Perceptual Organization Organizing raw sensory stimuli into meaningful experiences involves cognition, a set of mental activities that includes thinking, knowing, and remembering. Knowledge and experience are extremely important for perception, because they help us make sense of the input to our sensory systems. To understand these ideas, try to read the following passage:
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4. You could probably read the text, but not as easily as when you read letters in their usual orientation. Knowledge and experience allowed you to understand the text. You could read the words because of your knowledge of letter shapes, and maybe you even have some prior experience in reading text upside down. Without knowledge of letter shapes, you would perceive the text as meaningless shapes, just as people who do not know Chinese or Japanese see the characters of those languages as meaningless shapes. Reading, then, is a form of visual perception.
5. Note that in the example above, you did not stop to read every single letter carefully. Instead, you probably perceived whole words and phrases. You may have also used context to help you figure out what some of the words must be. For example, recognizing upside may have helped you predict down, because the two words often occur together. For these reasons, you probably overlooked problems with the individual letters—some of them, such as the n in down, are mirror images of normal letters. You would have noticed these errors immediately if the letters were right side up, because you have much more experience seeing letters in that orientation.
6. How people perceive a well-organized pattern or whole, instead of many separate parts, is a topic of interest in Gestalt psychology. According to Gestalt psychologists, the whole is different than the sum of its parts. Gestalt is a German word meaning configuration or pattern.
7. 1. Thelaw of similarity says that we will tend to group similar items together, to see them as forming a gestalt, within a larger form. Here is a simple typographic example:
8. OXXXXXXXXXX XOXXXXXXXXX XXOXXXXXXXX XXXOXXXXXXX XXXXOXXXXXX XXXXXOXXXXX XXXXXXOXXXX XXXXXXXOXXX XXXXXXXXOXX XXXXXXXXXOX XXXXXXXXXXO It is just natural for us to see the o’s as a line within a field of x’s .
9. we perceive rows of objects instead of columns or other arrangements.
10. 2. The law of proximity Things that are close together as seen as belonging together.
11. ************** ************** ************** You are much more likely to see three lines of close-together *’s than 14 horizontal collections of 3 *’s each.
12. 3. The law of symmetry Take a look at this example: [ ][ ][ ] Despite the pressure of proximity to group the brackets nearest each other together, symmetry overwhelms our perception and makes us see them as pairs of symmetrical brackets.
13. 4. The law of continuity When we can see a line, for example, as continuing through another line, rather than stopping and starting, we will do so, as in this example, which we see as composed of two lines, not as a combination of two angles...:
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15. In the drawing above, we see a straight line with a curved line running through it. Notice that we do not see the drawing as consisting of the two pieces in the drawing on the right.
16. 5. The law of closure, we prefer complete forms to incomplete forms. Thus, in the drawing below, we mentally close the gaps and perceive a picture of a duck. This tendency allows us to perceive whole objects from incomplete and imperfect forms.
17. 6. Figure-ground rule another Gestalt psychology principle. It was first introduced by the Danish phenomenologist Edgar Rubin (1886-1951). The classic example is this one...
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19. Basically, we seem to have an innate tendency to perceive one aspect of an event as the figure or fore-ground and the other as the ground or back-ground. There is only one image here, and yet, by changing nothing but our attitude, we can see two different things. It doesn’t even seem to be possible to see them both at the same time!