This article throws light upon the six main principles of perceptual organisation. The principles are: 1. Closure 2. Pragnanz 3. Proximity 4. Similarity 5. Continuity 6. Inclusiveness.
Principle # 1. Closure:
Gestalt psychologists claimed that when we receive sensations that form an incomplete or unfinished visual image or sound, we tend to overlook the incompleteness and perceive the image or sound as a complete or finished unit. This tendency to fill in the gaps is referred to as closure.
Show figure 7.2 to your friend for a brief time. The partial outlines of the figure will be filled out and your friend might say that it is a square, though it is not, in-fact, one. But even if it is seen as an incomplete square it shows that your friend first saw a square and later registered its incompleteness. This illustrates that the principle of closure was in operation. This shows a tendency to perceive meaningful objects.
Principle # 2. Pragnanz:
The term pragnanz indicates fullness or completeness. Gestalt psychologists are of the view that the process of perception is dynamic and goes on changing until we reach a stage of perceiving with maximum meaning and completeness. Once we reach this point, the perceived gestalt remains stable. Such a stable gestalt is called a good gestalt.
The perceptual process according to gestalt psychology tends to move towards a good gestalt. This phenomenon is very obvious in the case of children. If once they perceive something, they keep on asking questions about it which may appear silly to an adult. Closure is one basic mechanism which illustrates the principle of pragnanz.
The reader should not confuse between perceiving a good gestalt and the accuracy of perception. The term good gestalt means that at that stage the perceptual process is stable and that under given conditions a clear figure-ground demarcation has been arrived at.
Apart from the above principles, other principles which play a role in the organisation of perception are proximity, similarity, continuity, etc. They explain how perception takes place in the presence of a large number of stimuli. Perceptual organisation, under such circumstances, is determined to a great extent by the laws of association-similarity, continuity, etc. These principles are explained with the aid of illustrations below.
Principle # 3. Proximity:
When objects are close to each other, the tendency is to perceive them together rather than separately. Even if the individual items do not have any connection with each other they will be grouped under a single pattern or perceived as a meaningful picture (Fig. 7.3).
For instance, when the English teacher in the class questions a student, ‘What is often?’ This is completely different from the question, ‘What is of..ten?’Both the sentences contain the same sounds but the way the speaker groups the sounds and where he pauses will determine how the sounds are perceived.
Principle # 4. Similarity:
Similar elements tend to be perceived as belonging together. Stimuli that have the same size, shape and colour tend to be perceived as parts of the pattern as shown in Fig.7.4
Principle # 5. Continuity:
Anything which extends itself into space in the same shape, size and colour without a break is perceived as a whole figure (Fig. 7.5). For example, when several dots form a curved line, an individual may perceive the figure as two different continuous lines irrespective of the factors like proximity and similarity of the dots. Thus, the whole figure is organised into a continuum though the dots are unconnected (Fig.7.5).
Principle # 6. Inclusiveness:
The pattern which includes all the elements present in a given figure will be perceived more readily than the other figures. For example, in Fig.7.6 the hexagonal figure formed by all the dots may be perceived more readily than the square formed by the four middle dots. Single dots at either end act as a fence or enclosure within which all the other elements are included.
We have here examined some of the factors which play a role in the organisation of perception. These principles explain how perception is often independent of characteristics of individual stimuli. While discussing the phenomena of sensation it was mentioned that often our perception bears very little connection to the actual stimulus situation. We now know that this is because of the fact that perception is a complex and active process influenced by many factors other than stimulus characteristics.