Outline Introduction – larger units of knowledge The challenge Acquiring a text message is like concept acquisition in childhood, but faster Three influences on comprehension The reader’s knowledge The structure of the text The interaction of these two 5:15 AM

Introduction In Chapter 9, we looked at how concepts are mentally represented and accessed. Concepts might be stored as abstract representations (e.g., prototypes) or as a set of experiences with exemplars. Chapter 11 is about how we deal with knowledge at a larger scale – for example, the scale of texts. 5:15 AM

Introduction To make the distinction clear: Whale is a concept Moby Dick is a text, in fact, a story about a whale and the man who hunted it. A text is a very large unit of knowledge. How can we store it in memory? 5:15 AM

The Challenge Think about acquiring concepts in childhood. involves repetition and successive refinement e.g, doggie – first, all four-legged animals, then, small four-legged animals, then dogs. as children, we have years to accomplish this 5:15 AM

The challenge Reading a text, we go through a similar process with larger units in a much shorter time – perhaps minutes. Reading a text, we have to acquire and hold in memory a representation of what the text is about. ‘Reading a text’ may mean reading words written on a page or reading a situation. 5:15 AM

3 influences on text comprehension The task is to read and remember a text-level message. What influences our ability to encode, store, and retrieve larger units of meaning? The reader’s knowledge The structure of the text The interaction of these two 5:15 AM

3 influences on text comprehension The reader’s knowledge The structure of the text The interaction of these two 5:15 AM

The reader’s knowledge What kind of knowledge influences comprehension? Schema knowledge Which processes do schemas influence? Schemas have effects at both encoding, and retrieval. 5:15 AM

Schema effects at encoding Bransford & Johnson (1973) Balloon serenade passage. Context provided schema. D.V. = # of propositions remembered No context, 3.6. Context after reading, 3.6. Context before reading, 8.0. Point: you can’t remember what you don’t comprehend. 5:15 AM

Schema effects at retrieval Dooling & Christianson (1973) Read this passage: Carol Harris was a problem child from birth. She was wild, stubborn, and violent. By the time Carol turned eight, she was still unmanageable. Her parents were very concerned about her mental health. There was no good institution in her state. Her parents finally decided to take some action. They hired a private teacher for Carol. 5:15 AM

Dooling & Christianson (1973) 2 groups asked to read that passage 1 week later, subjects asked whether following sentence was in passage: “She was deaf, dumb, and blind.” One group got no further information. One group told, just before recall, story was really about Helen Keller. 5:15 AM

Dooling & Christianson (1973) Results Very few people in the control group said ‘Yes,’ (e.g., test sentence was in passage) Many people told that the story was about Helen Keller said ‘Yes’ to test sentence Retrieval process influenced by world knowledge, including knowledge of who Helen Keller was. 5:15 AM

Schema effects - conclusions Bransford & Johnson: without schema, passage was difficult to understand and encode. Schema made memory performance more accurate. Dooling & Christianson: without schema, passage easy to comprehend. Schema produced a retrieval error. 5:15 AM

Schema effects - conclusions Schemas can have positive or negative effects at both encoding and retrieval. If what you’re seeing or recalling is schema-consistent, schema will help. If what you’re seeing or recalling is schema-inconsistent, schema will hinder. Which is more likely? 5:15 AM

3 influences on text comprehension 1. The reader’s knowledge 2. The structure of the text 3. The interaction of these two 5:15 AM

The structure of the text Comprehension and memory for text are affected by: A story’s global structure. A story’s local detail. To illustrate the difference, let’s look at Bernstein’s West Side Story and the play it’s based on, Romeo & Juliet 5:15 AM

Romeo & Juliet vs. West Side Story Global structure (very briefly): feuding social groups young lovers from opposing sides their love overwhelms reason dire results 5:15 AM

Romeo & Juliet vs. West Side Story Local detail: R&J WSS Capulets & Montagues Jets & Sharks (gangs) 16th century Europe 20th century USA Horses, swords Cars, guns 5:15 AM

Global structure vs. local detail Both influence comprehension. Changing global structure may impair comprehension – consider movie Memento: No theme or plot to work with. Aspects of local detail may also affect ease of understanding and memory for a text 5:15 AM

Global structure vs. local detail We’ll examine both levels in turn. First, we’ll consider Thorndyke’s ‘grammar of storytelling,’ a model of the global structure in a story. Then, we’ll look at some local detail effects on comprehension and memory 5:15 AM

Thorndyke’s grammar of storytelling Developed a grammar of story-telling. Basic idea is very similar to grammar of a sentence: sentences have hierarchical structure as in example on next slide Thorndyke: stories have analagous structure. 5:15 AM

 Noun Phrase  Verb Phrase  Sentence    Noun Phrase  Verb Phrase       Determiner Adjective Noun Verb Adverb The good student read happily 5:15 AM

Thorndyke’s grammar of storytelling Just as a sentence contains phrases that in turn contain words. Stories consist of a Setting a Theme a Plot, and a Resolution. Each of these contains sub-components. 5:15 AM

Thorndyke’s grammar of storytelling Setting  characters + location + time Theme  event + a goal Plot  episodes Resolution  subgoal + attempt + outcome Experiments show that manipulating story structure influences both comprehension and memory performance. 5:15 AM

Effects of local detail - outline Internal structure at level of local detail Definition of proposition 2 processes for building structure: Referring a comment back to a topic Building bridges between propositions Building bridges – empirical evidence Haviland & Clark (1974) Kintsch (1974) 5:15 AM

Effects of local detail Texts have structure at a lower level, the level of local detail. Local structure is made of propositions During reading, that structure is built through two processes: Referring a comment back to a topic within a proposition. Building bridges between propositions. 5:15 AM

Propositions In reading, you interpret and store a passage as a structured set of propositions. A proposition is the smallest unit of meaning that can be true or false. Dog – no sense in which this can be true or false. The dog is blue – this can be true or false. 5:15 AM

Building structure out of propositions Process #1: Referring a comment back to a topic The dog I saw that lady with the flowered hat walking yesterday was a spaniel. The more propositions appear between topic and comment, the tougher comprehension is. 5:15 AM

Building structure out of propositions Process #2: Bridging between two ideas. “John threw a cigarette out of his window while driving through the forest. The fire destroyed hundreds of acres.” Here, reader adds an implicit proposition: The cigarette caused the fire. Comprehension is easier if bridging propositions are explicit . 5:15 AM

Building structure out of propositions: evidence Haviland & Clark (1974) –Task: press button when you comprehend second sentence. 1. Horace got some beer out of the trunk. 2. The beer was warm. 1. Horace was especially fond of beer. 2. The beer was warm. 5:15 AM

Haviland & Clark (1974) - Results People responded faster in condition A than in condition B. Conclusion: In B, extra time was necessary to make the bridge – to work out that beer in the second sentence was related to beer in the first sentence. This was easier in A. 5:15 AM

Building structure out of propositions - evidence Kintsch (1974) Gave subjects sentences like the one about John and the fire above. Tested their memory either immediately after reading or 20 minutes later. Immediate test: Memory better for explicit propositions. Later test: Memory equal for two kinds. 5:15 AM

Kintsch (1974) - Conclusion Text structure is developed as passage read. When new information is integrated into that text structure, surface form of text (the actual words) can be discarded. Passage stored in memory as Propositional structure. Implicit and explicit propositions are equal in that structure. 5:15 AM

3 influences on text comprehension The reader’s knowledge The structure of the text The interaction of these two 5:15 AM

Integrating reader’s knowledge & text Dominant figure here is Walter Kintsch. Van Dijk & Kintsch (1978) argued for three different levels of representation of texts: Surface code Textbase Situation model 5:15 AM

Van Dijk & Kintsch’s model Surface code represents a text using the actual words in the text. Textbase represents a text as propositions (explicit and implicit). Situation model – a mental model; integrates text information with pre-existing world-knowledge (also in proposition form, but more elaborate than textbase). 5:15 AM

Knowledge about the world + text Surface Code Situation Model Knowledge about the world + text Surface Code The text Textbase Knowledge about the text 5:15 AM

Van Dijk & Kintsch’s model Basic elements of model: Comprehension is an active process. Explicit propositions are extracted from surface code Implicit propositions are inferred All propositions are organized around structure reader expects (setting, conflict, etc.) 5:15 AM

Van Dijk & Kintsch’s model Comprehension also involves higher level processes. As propositions are extracted from the text: world knowledge lets you fill in missing parts from semantic memory parts not relevant to reader’s goals can be deleted. 5:15 AM