The information processing model is an analogy used in cognitive psychology for the way an individual records, synthesizes, and retrieves information. It models the human brain to a computer that processes external information and produces a reaction. Within the model, short-term memory and long-term memory are analogous to a computer's processor and hard drive. A person's five senses that perceive environmental stimuli are the brain's input devices. The model follows the progressive flow of information through the brain from input, through storage, to eventual output.
Historically, cognitive psychology was a departure from traditional pure behavior based models of thought. The behaviorism model focused on the observable response of an individual to a given stimulus, whereas cognitive psychology looks at how information is used by and within the brain. With the advent of computer use in the 1950s and 1960s, the information processing model arose after comparing the mechanics of the way a computer handles data storage and retrieval to the human mind.
Input devices used by the brain are visual and auditory perception, augmented and sometimes substituted by the other senses. Sensory memory is the first stop for all recorded information in the brain, and it is constantly refreshing and re-perceiving input. This stage of memory does not last very long, and its focus is limited only by an individual's attention span.
Once information is recorded by sensory memory, it is processed using short-term memory. All consciousness and data processing occurs in short-term memory. It is the most limited type of memory, both in capacity and duration. In the information processing model, the brain's short-term memory is the computer's central processing unit. The number of information bits able to be processed at one time is capped and restricted, but it can be improved and lengthened through repetition and data grouping.
After being processed by short-term memory, information can be stored for the long-term. Information is moved from one stage to the next by being associated to prior knowledge or past experiences. Long-term memory is practically unlimited in duration and capacity. Various techniques can be used to improve the storage of memories, such as those that combine sensory input like relating a piece of information to a known image. Different styles of memorization work well for different types of learners, and individuals can learn and be taught new techniques.
The information processing model is a serial process, meaning one step has to be finished before the next can proceed. Parallel processing is possible through multi-tasking and increased skill for a task. This is a limit of the model, as is the fact that the human brain differs from a computer as a result of emotion and motivation. Resource allocation is also a consideration with parallel thinking, and may influence how well information is stored. Errors are possible throughout the course of the model, both through recording by misunderstanding and in retrieval by mis-recollection.