PERCEPTION

Meaning:

When things come into contact with any of our sense organs, we feel sensation. When brain comes to know the form of these sensations, it comes to know the stimulus fully. This cognitive experience of the brain is called perception.

Perception is the process by which an organism interprets sensory input so that it acquires meaning. i.e. Perception = sensation + meaning (interpretation).

Definition:

1. Perception is the process of getting to know objects and objective facts by use of senses – Woodworth.

2. Perception refers to the complex processes which begin with the stimulation of a sense organ and end with an interpretation of the resulting neural activity by the organism i.e. with the meaning of the stimulus – James A. Dyal.

All knowledge of the world is ultimately obtained thorough sensory experiences. Sensation alone is meaningless and it will not result in acquisition of knowledge. Sensation is to be followed by application of mind. Then it results in perception. In other words we can say that the first response to a stimulus is sensation and perception is the next response following sensation.

Nature of Perception

1. Perception is meaningful.

2. Perception is selective.

3. Perception is based on sensation.

4. Perception is preventive and representative process of mind.

5. Perception needs observation / experience.

6. Perception makes use of images.

7. Perception is both analytic and synthetic.

8. In perception sensory data gets enriched.

Errors of Perception

It is quite possible that the same object may be perceived differently by different people or by the same person on different occasions. There are two errors of perception namely illusion and hallucination.

Illusion: A wrong perception is called illusion. A state in which errors of perception are immediately confirmed by experience is called an illusion. In illusion we take a wrong meaning of the stimulus present before us. It is related with the stimulus. For example, at dim light the rope that we find on the way is taken for a snake. An average sized man appears to be taller in a group of short men than in a group of tall men. One error may result from inadequate stimulation, poorly functioning sense organs or incorrect interpretation of sensations.

Common types of illusions:

1. Illusion regarding distance

2. Illusion regarding size and shape of the things

3. Illusion regarding colour

4. Illusion regarding movement and speed

Causes for Illusion:

1. Irregular or unusual conditions in the external world

2. Defects in sensory organs

3. Anticipation expectation and suggestions

4. Interest and habits

5. Previous experience and present selfishness

6. Present aptitudes

Hallucination: Hallucination is false perception. Here, a person experiences of the stimulus even in the absence of it. For example, at night a person may see a ghost when practically there is no stimulus either in the form of a human figure or anything resembling it. This is a case of hallucination. There is no stimulus in hallucination and memory image is taken for perception.

A hallucination is a mental state in which a person begins to perceive something in spite of the absence of any external stimulus. There are two kinds of hallucinations.

1. Visual Hallucination: A hallucination which occurs in the sphere of vision is called a visual hallucination, and it means seeing an object which is not in front of eyes at all.

2. Auditory Hallucination: The hallucination which occurs in the sphere of hearing is called auditory hallucination. For example, while sitting in solitude / loneliness, we may suddenly feel, that someone is calling us, through, in reality no one has called us. 

Causes for Hallucination:

1. More but vague and irrelevant continuous thinking

2. Excessive imagination or day-dreaming

3. The will and desire in the unconscious mind

4. Hysteria / madness, schizophrenia and other related mental diseases

Factors related to Perception

There are several factors involved in perception. They are categorized under two types namely, external and internal factors.

External Factors:

1. Similarity: Similar elements tend to be perceived as belong together and they are viewed as wholes. Stimuli that have the same size, shape and colour tend to be perceived as parts of the pattern.

1. 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.

1. Continuity: anything which extends itself into space in the same shape, size and colour without a break is perceived as awhole figure. For example, several dots from 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 organized into a continuum though the dots are unconnected.

1. Inclusiveness: The pattern which includes all the elements present in a given figure will be perceived more readily than the other figures. 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.

1. Closure: Closed areas more readily form in group. The illusion of figure was caused by closure which did not allow the attention to dwell on by gaps, so that the figures appeared organized.  

Internal Factors:

1. Familiarity: An organisation with which the person is aquatinted, is perceived easily and with enthusiasm. Seeing a familiar picture quiz, we at once understand its reality and solution and the remaining figure forms no obstacle in this. But if the aquatinted person is affected by some other part of the picture, he will be incapable of recognizing it, not withstanding his familiarity.

2. Mental Set: Mental set has a by no means insignificant effect upon the organization of the sensation. One of the causes of mental set is habit. For example, a philosopher looks at the truths of the universe, while a trader is always involved in worthy things.

3. Reinforcing Factors: These include pregnance and good figure. The supplementing of the incomplete is a mental tendency, which diverts our attention from gaps and presents a whole. The idea of good figure is explained by the picture, in the description of closure.