Schema (psychology)

In psychology and cognitive science, a schema is a mental structure that represents some aspect of the world. People use schemas to organize current knowledge and provide a framework for future understanding. Examples of schemas include stereotypes, social roles, scripts, worldviews, and archetypes. In Piaget's theory of development, children adopt a series of schemas to understand the world.

The importance of schemas for thought cannot be understated. Sufferers of Korsakov's syndrome are unable to form new memories, and must approach every situation as if they had just seen it for the first time. Many sufferers adapt by continually forcing their world into barely-applicable schemas to the point of incoherence and self-contradiction.

Thought using schemas

Schemas are an extremely effective tool for understanding the world. Through the use of schemas, most everyday situations do not require effortful thought — automatic thought is all that is required. People can quickly organize new perceptions into schemas and act effectively without effort. For example, most people have a stairway schema, and can apply it to climb staircases they've never seen before.

Schemas are often related to one another, and multiple conflicting schemas can be applied to the same information. Schemas are generally thought to have a level of activation, which can spread among related schemas. Which schema is selected can depend on factors such as current activation, accessibility, and priming.

Accessibility is how easily a schema comes to mind, and is determined by personal experience and expertise. This can be used as a cognitive shortcut; it allows the most common explanation to be chosen for new information. See availability heuristic.

With priming, a brief imperceptible stimulus temporarily provides enough activation to a schema so that it is used for subsequent ambiguous information. Although this may suggest the possibility of subliminal messages, the effect of priming is so fleeting that it is difficult to detect outside laboratory conditions. Furthermore, the mere exposure effect — which requires consciousness of the stimuli — is far more effective than priming.

Modification of schemas

New information that falls within an individual's schema is easily remembered and incorporated into their worldview. However, when new information is perceived that does not fit a schema, many things can happen. The most common reaction is to simply ignore or quickly forget the new information. This can happen on a deep level — frequently an individual does become conscious of or even perceive the new information. However, when the new information cannot be ignored, existing schemas must be changed.

Assimilation is reuse of schemas to fit the new information. For example, when an unfamiliar dog is seen, a person will probably just assimilate it into their dog schema. However, if the dog behaves strangely, and in ways that don't seem doglike, there will be accomodation as a new schema is formed for that particular dog.