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Information-Processing Theory



A leading orientation in experimental psychology that focuses on how people select, process, and internalize information and how they use it to make decisions and guide their behavior.

The information-processing theory is associated with the development of high-speed computers in the 1950s. Researchers—most notably Herbert Simon and his colleagues—demonstrated that computers could be used to simulate human intelligence. This development led to the realization that computer-oriented information-processing models could provide new insight into how the human mind receives, stores, retrieves, and uses information. The information-processing theory was one of several developments that ended the decades-long dominance of behaviorism in American psychology. It focused on innate mental capacities, rather than on conditioned, externally observable behavior. By enabling experimental psychologists to test theories about complex mental processes through computer simulation, information-processing models helped reestablish internal thought processes as a legitimate area of scientific inquiry.



The information-processing theory of human cognition encompasses several basic stages. Information received from external or internal stimuli is inputted through the senses and transformed by a variety of mental operations (including representation by symbols). It receives attention through the perceptual processes and is stored in either short-term or long-term memory, where it interacts with previously stored information to generate a response, or output. These stages may take place in a number of different arrangements. The simplest is the serial model, in which the stages occur in succession like a chain reaction, with the output of each stage becoming the input of the succeeding one. However, stages can also occur simultaneously, a phenomenon known as parallel processing. Serial and parallel processing can also be combined in what are known as hybrid models. Another important characteristic of information-processing models is resource allocation—the way in which energy is distributed in the system. This refers to the fact that the efficiency of each stage in the process may depend on whether certain other stages are operating at the same time.

One of the many areas investigated through the use of information-processing models is human error. Errors that occur during the early stages of processing, such as misunderstandings, are called mistakes, as distinguished from slips, which occur during the selection or execution of responses. The increased understanding of error provided by information-processing models has been useful in eliminating a variety of technical and industrial problems by isolating and addressing their causes. Those problems classified as mistakes often involve the size of an information load and the way it is handled, while slips are commonly remedied by redesigning instruments and equipment so they can be used more efficiently.

Another area that has been investigated using information-processing theory is reaction time—the amount of time needed to respond to a stimulus in a particular situation. Reaction time is an important feature in the design of automobiles and many other products. Factors influencing reaction time include complexity of the decision required before action can be taken; stimulus-response compatibility (the physical convenience of the reaction); expectancy (it takes longer to respond to an unexpected stimulus); and the relative importance of speed and accuracy in the required response.

Further Reading

Johnson-Laird, Philip N. The Computer and the Mind: An Introduction to Cognitive Science. Cambridge, MA: Harvard University Press, 1988.

Lindsay, Peter H. Human Information Processing: An Introduction to Psychology. San Diego: Academic Press, 1977.

Newell, A., and H. A. Simon. Human Problem Solving. Englewood Cliffs, NJ: Prentice-Hall, 1972.

Additional topics

Psychology EncyclopediaPsychological Dictionary: Ibn Bajjah (Abu-Bakr Muhammad ibn-Yahya ibn-al-Saʼigh, c.1106–38) Biography to Perception: cultural differences