Margaret W. Matlin, Cognition, 8E Outline Chapter 8 Page 1 of 14

Margaret W. Matlin, Cognition, 8e Outline Chapter 8 Page 1 of 14

CHAPTER 8

General Knowledge

Chapter Introduction

inference

semantic memory

schemas

We have an enormous amount of information about the world, and we use this information efficiently and accurately.

When people are given one specific piece of information, they can build on this specific information.

The Structure of Semantic Memory

semantic memory

episodic memory

Background on Semantic Memory

Semantic memory includes general knowledge, lexical or language knowledge, and conceptual knowledge.

In Depth: The Prototype Approach and Semantic Memory

Eleanor Rosch

· organize each category on the basis of a prototype, the item that is most typical and representative of the category

· prototype approach—decide whether an item belongs to a category by comparing that item with a prototype

· members of a category differ in prototypicality

· graded structure—members of categories are not all created equal

Characteristics of Prototypes

1. Prototypes are supplied as examples of a category.

Mervis and colleagues (1976)

· prototype ratings for examples of categories

· Items rated most prototypical were the same items that other people had supplied most often in the category norms.

Results account for typicality effect—when judging whether an item belongs to a particular category, typical items judged faster than atypical items

2. Prototypes are judged more quickly than nonprototypes, after semantic priming.

· semantic priming effect—People respond faster to an item if it was preceded by an item with similar meaning.

· Priming facilitates responses to prototypes more than it facilitates responses to nonprototypes.

· Priming inhibits judgments for nonprototypes. (Rosch color studies)

3. Prototypes share attributes in a family resemblance category.

family resemblance

· no single attribute shared by all examples of a concept

· Each example has at least one attribute in common with some other example of the concept.

Rosch and Mervis (1975)

· prototypicality judgments about members of several categories

· list the attributes possessed by each item

· The most prototypical item shared the largest number of attributes with the other items in the category.

In Depth: The Prototype Approach and Semantic Memory (continued)

Levels of Categorization

super-ordinate-level categories

basic-level categories

subordinate-level categories

1. Basic-level names are used to identify objects.

Rosch and colleagues (1976)

· Ask people to look at pictures and identify objects.

· People prefer to use basic-level names.

· People produce basic-level names faster than superordinate or subordinate names.

· When presented with superordinate or subordinate names, people frequently remember the basic-level version when later tested for recall.

2. Basic-level names are more likely to produce the semantic priming effect.

· Priming with basic-level names is helpful.

· Priming with superordinate names is not helpful.

3. Different levels of categorization activate different regions of the brain.

· Superordinate terms are more likely than basic-level terms to activate part of the prefrontal cortex.

· Subordinate terms are more likely than basic-level terms to activate part of the parietal region.

In Depth: The Prototype Approach and Semantic Memory (continued)

Applying the Prototype Approach to Social Relationships

1. The Prototype of Compassionate Love

Fehr and Sprecher (2009)

· list the characteristics of "compassionate love"

· divide into characteristics listed most, moderate, and seldom

· prototypicality ratings

· typicality effect

2. The Prototype of "Being There" for a Romantic Partner

Turan and Horowitz

· attributes

· usefulness

· Knowledge of Indicators Scale

· validity

· listening task: "another student" describes a relationship problem

· Students who had high scores on the Knowledge of Indicators Scale were also more likely to remember the details about the conversation about a relationship.

Conclusions About the Prototype Approach

· can account for our ability to form concepts for groups that are loosely structured

· can be applied to social relationships, inanimate objects, nonsocial categories

Problems

· concepts can be unstable and variable (e.g., prototype ratings can shift)

· We often do store specific information about individual examples of a category, not just prototypes.

The Exemplar Approach and Semantic Memory

exemplar approach—first learn some specific examples of a concept (exemplars), then classify each new stimulus by deciding how closely it resembles those specific examples

Example: case studies in a course on psychological disorders

A Representative Study on the Exemplar Approach

Demonstration 8.2: Exemplars and Typicality

Heit and Barsalou (1996)

· seven basic-level categories; provide first example that comes to mind

· categories and examples rated in terms of typicality (by different students)

· Researchers try to create an equation to predict the typicality of the categories based on the exemplars.

· need to take into account the frequency and typicality ratings of the exemplars

· Exemplar frequency and exemplar typicality accurately predicted which of the seven categories were most typical for the superordinate category "animal."

· When asked a question about a category, people don't just consider prototypes, they also include information about less typical examples of the category.

Comparing the Exemplar Approach with the Prototype Approach

· make decisions about category membership by comparing to a stored representation (like prototype approach), but the stored representation is a collection of numerous specific members of the category, not a typical member

· do not need to perform any kind of abstraction process which would force you to discard useful, specific data about individual cases

Problems

· The exemplar approach may be more suitable for categories with relatively few members (so as not to overwhelm semantic memory).

· The prototype approach may be more suitable for categories with numerous members.

· Individual differences in representations may be substantial.

Conclusions

· Semantic memory is quite flexible.

· Both approaches may coexist.

· different hemispheres (left—prototypes; right—exemplars)

· People may use a combination of prototype strategies and exemplar strategies when forming categories in everyday life.

Network Models and Semantic Memory

network models

· propose a netlike organization of concepts in memory

· many interconnections

· meaning of a concept depends on the concepts to which it is connected

node

spreading activation

Anderson's ACT-R Approach

ACT-R—Adapted Control of Thought-Rational

attempts to account for a wide variety of cognitive tasks

declarative knowledge

propositional network

proposition—smallest unit of knowledge that can be judged either true or false; abstract representation

· Each concept in a proposition can be represented by its own network.

· Practice increases the strength of links between nodes.

· fMRI research examines how changes in learning are reflected in selected regions of the cortex and subcortex.

The Parallel Distributed Processing Approach

parallel distributed processing (PDP) approach

· Cognitive processes can be represented by a model in which activation flows through networks that link together a large number of simple, neuron-like units.

· networks rather than specific locations in the brain

· also called: connectionism, neural networks

The Parallel Distributed Processing Approach (continued)

Four General Characteristics of PDP

1. Cognitive processes are based on parallel operations, rather than serial operations. Therefore, many patterns of activation may be proceeding simultaneously.

2. A network contains basic neuron-like units or nodes, which are connected together so that a specific node has many links to other nodes. PDP theorists argue that most cognitive processes can be explained by the activation of these networks.

3. This process of spreading information from one node to other nodes is called spreading activation. A concept is represented by the pattern of activity distributed throughout a set of nodes.

4. Consistent with the concept of situated cognition, the current context often activates only certain components of a concept’s meaning.

Additional Concepts of PDP

· serial search vs. parallel search

· Memory can cope with partial and/or partly incorrect information.

· Characteristics are connected in a mutually stimulating network.

· spontaneous generalization—draw a conclusion about a general category

· default assignment—draw a conclusion about a specific member of a category

Theoretical Features of PDP

1. The connections between these neuron-like units are weighted, and the connection weights determine how much activation one unit can pass on to another unit.

2. When a unit reaches a critical level of activation, it may affect another unit, either by exciting it (if the connection weight is positive) or by inhibiting it (if the connection weight is negative).

3. Every new piece of information you learn will change the strength of connections among relevant units by adjusting the connection weights.

4. Sometimes we have only partial memory for some information, rather than complete, perfect memory. The brain’s ability to provide partial memory is called graceful degradation (e.g., tip-of-the-tongue phenomenon, brain function after accident or stroke)

Current Status of Theory

· generally consistent with the neurological design of neurons and the brain

· works better for tasks in which several processes typically operate simultaneously

· Tasks requiring serial processing may be accounted for by other models.

Schemas and Scripts

schema—generalized knowledge about a situation, an event, or a person

Schema theories are especially helpful when psychologists try to explain how people process complex situations and events.

Background on Schemas and Scripts

Schema theories propose that people encode "generic" information about a situation, then use this information to understand and remember new examples of the schema.

"This is just like what happened when . . ."

How Schemas Relate to the Themes of This Book

· top-down and bottom-up processing

· heuristic

· active processing

· schemas can lead to errors

· Errors usually make sense within the framework of that schema.

Schemas Throughout Psychology

· Piaget

· Bartlett

· social psychology

· schema therapy

Schemas and Scripts

· script—simple, well-structured sequence of events

· restaurant script

· life scripts

Identifying the Script in Advance

Scripts are recalled more accurately if identified in advance.

Demonstration 8.4: Trafimow & Wyer (1993)

· scripts with irrelevant details

· script-identifying event either first or last

· recall events

· Event recall was higher when the script-identifying event was presented first, rather than last.

Events in a sequence are much more memorable if you understand—from the very beginning—that these events are all part of a standard script.

Schemas and Memory Selection

Demonstration 8.5: Brewer and Treyens (1981)

· recall objects from an office waiting room

· highly likely to recall objects consistent with "office schema"

· "remembered" items that were not in the room, but were consistent with "office schema"

Neuschatz and coauthors (2002)

· "lecture schema"

People are more likely to recall schema-inconsistent material when that material is vivid or surprising.

Davidson (1994)

· read stories describing well-known schemas

· especially likely to recall schema-inconsistent events that interrupted the normal, expected story

General Conclusions about Schemas and Memory Selection

1. If the information describes a minor event—and time is limited—people tend to remember information accurately when it is consistent with a schema (e.g., the desk and the chair in the ‘‘office’’).

2. If the information describes a minor event—and time is limited—people do not remember information that is inconsistent with the schema (e.g., the wine bottle and the picnic basket).

3. People seldom create a completely false memory for a lengthy event that did not occur (e.g., the lecturer did not dance across the room).

4. When the information describes a major event that is inconsistent with the standard schema, people are likely to remember that event (e.g., the child who crashes into Sarah).

Schemas and Boundary Extension

Demonstration 8.6

boundary extension—our tendency to remember having viewed a greater portion of a scene than was actually shown

Intraub and colleagues

· see photo then draw replica of photo

· Participants consistently produced a sketch that extended the boundaries beyond the view presented in the original photo.

· activate a perceptual schema

relevance in eyewitness testimony situations

Schemas and Memory Abstraction

abstraction—a memory process that stores the meaning of a message but not the exact words

verbatim memory—word-for-word recall

The Constructive Approach

Bransford and Franks (1971)

· listen to sentences from several different stories

· recognition test including new items

· People were convinced that they had seen these new items before (false alarm).

· False alarms were particularly likely for complex sentences consistent with the original schema.

· False alarms were unlikely for sentences violating the meaning of the earlier sentences.

constructive model of memory—People integrate information from individual sentences in order to construct larger ideas; later, they cannot untangle the constructed information from the verbatim sentences.

Schemas and Memory Abstraction (continued)

The Pragmatic Approach

pragmatic view of memory—people pay attention to the aspect of a message that is most relevant to their current goals

1. People know that they usually need to accurately recall the gist of a sentence.

2. They also know that they usually do not need to remember the specific wording of the sentences.

3. However, in those cases where they do need to pay attention to the specific wording, then they know that their verbatim memory needs to be highly accurate.

Murphy and Shapiro (1994)—Insult Study

· read letters from "Samantha" to cousin or boyfriend

· bland vs. sarcastic comments

· recognition test on original, paraphrased, or irrelevant sentences

· Correct recognition was higher for sentences from the sarcastic condition than for sentences in the bland condition.

· more false alarms for paraphrases of bland sentences than sarcastic sentences

· more accurate verbatim memory for the sarcastic version than for the bland version

The Current Status of Schemas and Memory Abstraction

· two compatible approaches

· In many cases we integrate information into large schemas.