SCHEMA AN ORGANIZED FRAMEWORK OF KNOWLEDGE
Human cognitive processes involve knowledge units that are fairly larger. Our knowledge includes information about familiar situations, events, and the relationships about these situations and events. These generalized kinds of knowledge about situations and events are called schemata.
A schema represents"generic" information that includes not only events from one's 'life but also general knowledge about procedures, sequences of events, and social situations. Schemas guide our recognition and understanding of new examples by providing expectations about what should occur. Furthermore, schemata allow us to predict what will happen in a new situation. In most situations, these predictions will b~correct; Schemata are heuristics, or rules-of-thumb that are generally accurate.
Bartlett defined a schema as an "active organization of past reactions, or of past experiences, which must supposed to be operating in any well-adapted organic response" .. The key term here is organization. A Schema is thought to be a large unit of organized information used for representing concepts, situations, events, and actions in memory.
David Rumelhart and Andrew Ortony ( 1977) wrote an extensive analysis of schemas. Schemas have several characteristics that ensure wide flexibility in their use: They are :
(a) Schemas can include other schemas-for example, a schema for animals includes a schema for cows, a schema for apes and so on.
(b) Schemas encompass typical, general facts, which can vary slightly from one specific instance to another-for example, although the schema for mammals includes a general fact that mammals typically have fur, it allows for humans, who are less hairy than most other mammals.
(c) Schemas can vary in their degree of abstraction -for example, a schema for justice is much more abstract than a schemed for apple or even a schema for fruit.
Lloyd Komatsu (1992) has suggested that schemas also can include information about relationships. Some of this information includes relationships among :
• Concepts (e.g., the link between trucks and cars)
• Attributes within concepts (e.g., the height and the weight of an elephant),
• Attributes in related concepts (e.g., the redness of a cherry and the redness of an apple),
• Concepts and particular contexts (e.g., fish and the ocean),
• Specific concepts and general background knowledge (e.g., concepts about particular Indian Prime Ministers and general know ledge about the Indian government and about Indian.history).
SCHEMA THEORY
Schema theory was advocated by Bartlett. Schema theory is popular in explaining how people remember complex events.
The nature and the use of schemata can be illustrated by taking an example -the restaurant schema. Restaurant schema has been studied extensively because it is relatively simple and it concerns a frequently occurring episode.
Fig. 26.a A hypothetical schema for eating at a restaurant.
Bower, Black and Turner ( 1979) ~ave tested and prop~ed that people have a common restaurant schema. There was extensive agreement in the language people used to describe the event of eating at a restaurant. It was also found that the people divide the restaurant schema into similar components.
Using the Schemata
People might use the restaurant schema in comprehending a story about someone eating out. If someone said to you "I ate at a new restaurant today", the ward restaurant would activate your restaurant schema, thereby preparing you to hear about the quality of the food, fairness of the prices, and so on.
Advantages of Schemata
1) Schemata are advantageous because they have the power of prepositional representations, which are discussed in detail in Lesson-20.
2) Schemata are powerful because they can represent global, multifaceted objects or events in a unitary manner.
3) Schemata are useful in a wide range of activities such as global analysis and conceptually driven processing in perception.
4) The ability to construct and modify schemata contributes greatly to our ability to learn.
5) Schemas are essential in understanding how concepts are related in the mind.
As a schemata is used to pick up new information, it can be modified by the incoming information. Thus schemata are dynamic and subject to change.
THE PROCESSING OF PROSE
This section examines the importance of schemata in processing prose. It is difficult to activate and to apply an appropriate schema in reading a prose passage, which is difficult to comprehend, and if the central theme is obscure. The passage becomes easy to understand when we know what the topic is. By knowing the topic, one can relate each statement in the passage to the existing framework of knowledge - our schemata.
Thus two points can be stated :
i) People comprehend passages by relating incoming information to our existing frameworks of knowledge our schemata. Thus comprehension is an active process of interpretation in which people use the concepts and schemata that they know already.
ii) Schemata are activated by particular words or by other contextual information and the difficulty of Comprehension depends on the structure of the passage and on the availability of contextual information that activates the pertinent knowledge.
Evidence that schemata influence comprehensions has come from studies involving simple stories. Thorndyke hypothesized that in reading a story, people try to interpret the passage in terms of a schema that includes categories such as setting (where and when the event occurred), a theme (the main idea), a plot (what happened) and a resolution (the outcome of the story). Several studies have supported the view that readers use a story schema to guide comprehension.
People also use schemata in recalling stories. This view is backed by several lines of evidence.
Overall, the evidence from studies of comprehension and recall indicates that people use schemata in processing prose.
At present, schema theory is new and has been tested more extensively in computer science than in psychology. Yet, it is being applied in relative areas of cognitive psychology.
SUMMARY
The importance of world knowledge and inferences is highlighted in schema theories of comprehension. A schema is an organized framework of knowledge that describes objects, places or episodes. A schema for eating at a restaurant, for example, describes the sequence of events that occurs in eating at a restaurant-getting a table, ordering, eating and so on. Listeners use schemata in making inferences about the event, and to form expectations about what the speaker is to say. The evidence indicates that the comprehension and the recall of prose are facilitated when the listener uses an appropriate schema.