An ELT Glossary : Top-down processing
Using pre-existing "knowledge of the world" - eg knowledge of discourse conventions, topic, cultural or social norms - in order to interpret meaning while reading or listening.
Eg : If I hear "John is 18 and lives with his family in Leeds" - my interpretation of the make-up of John's family (mother, father, siblings) differs from the interpretation that I make if I hear "John is 48 and lives with his family in Leeds" (wife and children). The interpretation is, however, based on my knowledge of the world, not on the text itself, where the information is not explicitly stated..
For other examples of how this might happen see the related terms Schema and Inference, and for its application to the classroom see the article Teaching Listening : Top Down or Bottom Up?
Lynch, T. Teaching Listening Comprehension, Oxford
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