The perception involves the meaningful interpretation of the sensory input. Both Helmholtz and Gibson pointed to the importance of experience in explaining perception. The past experience prepares the individual to emphasize some sensory inputs and ignore others.
Gibson defined perceptual learning as increased ability to extract information from the environment as a result of experience with stimulation coming from it. An ornithologist can distinguish the calls of birds which normal people would find very difficult to do. The remarkable auditory sensitivity of the blind people is a matter of perceptual learning.
It is not true that the blind people are inherently more sensitive to auditory stimulation. In stead, the blind people, because of their necessity, learn to extract information from the environment not ordinarily used by the sighted people. These sorts of information help them to move around the world by avoiding obstacles with ease.
The impact of past experience is so great that persons wearing special goggles that invert their view of the world quickly adapt to their new world and do everything from reading a book to flying a plane (Kohler, 1962). Gibson provides many examples that demonstrate how perception is shaped by learning.
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Gibson and Walk (1956) raised rats from birth under two conditions. In the experimental condition, the walls of the cage in which the rats were reared up contained 4 metal plaques, two triangles and two circles. The walls of the control rat’s cages were plain and white. Three months after this treatment, the animals were given a learning task in which they had to discriminate between a triangle and a circle. It was observed that the experimental group of rats performed consistently better than the control group of rats, having about 90% correct choices, while the controls were still operating at a fifty-fifty chance level. The performance in the learning task was definitely influenced by the greater perceptual ability of the experimental rats, which had prior experience of triangles and circles.
Glenn (1965) made an interesting observation to explain the role of past experience in perception. He reported the experiences of a French expert in industrial management, who visited the United States to study the industrial policy and finance management in American industries. His objective was to gather knowledge for the rebuilding of French industrial set up. But he was disappointed as he visited more and more firms and industries in the United States. Finally, he wanted to know from the government officials why Americans were advocating for a free enterprise when in fact nearly all American industries were nationalized. When inquired as to how he arrived at such a conclusion, he pointed out that he had seen the United State’s national flag flying over each industry. In fact, he had wrongly perceived because of his past experience in France, where only nationalized industries fly national flags over their factory. On the other hand, there were no such restrictions in USA. Glenn pointed out that the perception of the French industrialist was influenced by his previous experiences of ownership of a factory in France.
An experiment of Bruner and Postman (1949) can be cited to account for the role of past experience in perception. Twenty-eight adult subjects were asked to name some playing cards exposed to them tachistoscopically. The cards contained some unusual ones like hearts in black shade and spades in red shade. You know that all hearts are red and all spades are black. Influenced by such type of past experiences, 27 out of 28 subjects perceived a red form of spade either as a red form of heart or a black form of spade. Thus, learning to extract information from the environment is of enormous practical and adaptive value. The past experience serves as a reference point for extracting information from the immediate environment.