P S Y C H O L O G Y T h i r d E d i t i o n by Drew Westen PowerPoint  Presentation C h a p t e r 6 M E M O R Y John Wiley & Sons, Inc.

Lecture Outline n Memory and mental representations n Working memory n Long-term memory n Encoding issues n Forgetting © 2002 John Wiley & Sons, Inc.

Memory n Memory is the process by which we observe, store, and recall information  Memories may be visual, auditory, or tactile n Memory processes may involve multiple systems  Conscious  Automatic © 2002 John Wiley & Sons, Inc.

Mental Processing n Mental Representations: A mental model of a stimulus or category of stimuli  Sensory representations Image of a dog Sound of a gun shot  Verbal representations Concept of “Freedom” Involve neural activation different from that of sensory representation  Motoric representations Memories of motor actions –Swinging a tennis racket © 2002 John Wiley & Sons, Inc.

The Information Processing Model of Memory © 2002 John Wiley & Sons, Inc.

Standard Memory Model n This metaphor views the “the mind as a computer” n Model assumes that memory consists of 3 stores:  Sensory registers Iconic (visual) Echoic (auditory)  Short-term memory (STM)  Long-term memory (LTM) © 2002 John Wiley & Sons, Inc.

Characteristics of STM n STM is a variant of memory that is of limited duration:  Information in STM fades after seconds (without rehearsal) n STM has limited capacity storage  STM capacity is about 7 items of information Capacity is constant across cultures n STM Involves rehearsal  Maintenance: information is repeated  Elaborative: information is related to other knowledge © 2002 John Wiley & Sons, Inc.

Rehearsal aids LTM (Figure adapted from Rundus, 1971) © 2002 John Wiley & Sons, Inc.

LTM n LTM refers to the representations of facts, images, actions, and skills that may persist over a lifetime n LTM involves retrieval of information n LTM is theoretically limitless in capacity n The serial position curve supports the existence of STM versus LTM  Primacy effect reflects LTM  Recency effect reflects STM © 2002 John Wiley & Sons, Inc.

The Serial Position Curve © 2002 John Wiley & Sons, Inc. (Figure adapted from Atkinson & Shriffrin, 1968) Recalled from LTM Recalled from STM

Working Memory © 2002 John Wiley & Sons, Inc. n Working memory is temporary storage and processing of information used to  solve problems  respond to environmental demands  achieve goals n Working memory may consist of three modules  Visual Memory Store  Verbal Memory Store  Central Executive

Working Memory Stores n Visual memory store  A temporary image (20-30 sec) that provides information about the location and nature of objects n Verbal memory store  Involves storage of verbal items Limited capacity Shallow: Items are processed in order of presentation and are subject to interference n Working memory stores are independent  Brain damage may alter visual but not verbal © 2002 John Wiley & Sons, Inc.

Working Memory and LTM n Evidence supporting a distinction between working memory and LTM  Working memory is easily accessed, but is limited in capacity  Neurological studies in which brain damage impairs memory LTM impairment: person shows normal working memory, but cannot transfer information to LTM Working memory deficit: person has a memory span of 2 digits, but normal LTM  Chunking: LTM information is used to increase item size in working memory (e.g. IBM, USC, CIA) © 2002 John Wiley & Sons, Inc.

Prefrontal Cortex and Working Memory n Working memory involves activation of the prefrontal cortex  Holding an image in working memory (memory delay) activates the prefrontal cortex © 2002 John Wiley & Sons, Inc. (Figure adapted from Courtney et al., 1997)

Varieties of LTM n Declarative memory  Semantic: “generic” knowledge of facts  Episodic: memories of specific events Autobiographical n Procedural memory: for skills n Explicit memory: Conscious retrieval of information  Recall versus recognition n Implicit memory: Skills, conditioned learning, and associative memory © 2002 John Wiley & Sons, Inc.

Overview of Long-Term Memory © 2002 John Wiley & Sons, Inc.

Studies of Everyday Memories © 2002 John Wiley & Sons, Inc. n Laboratory memory studies can be artificial (timing, what is memorized) n Studies of everyday memory examine the  Function of memory Our intent as we learn information –Male vs. female memory study  Emotional significance of memory Emotional memories may involve different neural mechanisms than do neutral memories  Prospective aspect of memory Emphasis is on time

Functional Aspects of Memory n Recall for information may be a function of our interest in the information:  Men show better recall for workbench construction details than details on how to make a shirt… © 2002 John Wiley & Sons, Inc.

Encoding in Long-Term Memory n Storage of information in LTM requires encoding as a function of meaning  Match between encoding and accessibility n Levels of processing: Notion that encoding can be  Shallow: the physical aspects of the stimulus  Deep: the meaning of the stimulus © 2002 John Wiley & Sons, Inc.

Encoding Issues n Encoding specificity principle: Idea that ease of retrieval of a memory depends on match of encoding with retrieval  Poor recall if shallow learning is examined using a deep processing technique Student who reads multiple choice items in test book and then takes an essay exam will likely not do very well n Spacing of learning is important  Spaced learning leads to better recall of information © 2002 John Wiley & Sons, Inc. Figure adapted from Herrmann et al., 1992)

Mnemonic Devices n Mnemonic devices add additional cues for retrieval to enhance memory  Method of Loci The contents of a physical location that you are familiar with is linked to the items you want to recall  Peg Method Imagery is combined with a verbal rhyme –“One is a bun” (imagine a quart of milk in a bun…)  SQ3R Method Survey, question, read, recite and review © 2002 John Wiley & Sons, Inc.

Networks of Association n LTM is organized in clusters of information that are related in meaning  The network is composed of interconnected nodes  A node may contain thoughts, images, smells, emotions, or any other information  Mnemonic devices allow one to add concepts to existing networks © 2002 John Wiley & Sons, Inc.

An Example of Interconnected Nodes © 2002 John Wiley & Sons, Inc.

Hierarchical Storage n Nodes in LTM may be organized in a hierarchy  Broad categories contain narrower categories n Hierarchical storage can lead to retrieval errors  “Which is farther north - Seattle or Montreal?” © 2002 John Wiley & Sons, Inc.

Forgetting n Forgetting refers to the inability to recall previously learned information n Ebbinghaus documented the rate of forgetting of information  Initial rate of forgetting is high and then trails off... © 2002 John Wiley & Sons, Inc.

Memory Accuracy © 2002 John Wiley & Sons, Inc. n Memory is subject to errors and biases  Memory can be primed Study in which subjects were presented with a list (slumber, nap, bed) of words that were related to the word “sleep” –Most subjects recalled the word sleep even though that word had not been presented to them  Memory is altered by emotional factors Study of recall of high school grades –Students misremembered their D’s but recalled their A’s

“Seven Sins of Memory” n Memories are transient (fade with time) n We do not remember what we do not pay attention to n Our memories can be temporarily blocked n We can misattribute the source of memory n We are suggestible in our memories n We can show memory distortion (bias) n We often fail to forget the things we would like not to recall (persistence of memory) © 2002 John Wiley & Sons, Inc.

Memory Misrecall © 2002 John Wiley & Sons, Inc. (Figure adapted from Bahrick et al., 1996)

Theories of Forgetting © 2002 John Wiley & Sons, Inc. n Decay theory  Memory is like a fading neural trace that is weakened with disuse n Interference theory: conflict between new and old memories  Proactive: old memories interfere with recall of new information  Retroactive: new memories interfere with recall of old information n Motivated forgetting implies that forgetting can avoid painful memories

Copyright Copyright 2002 by John Wiley & Sons, Inc., New York, NY. All rights reserved. No part of the material protected by this copyright may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without written permission of the copyright owner. © 2002 John Wiley & Sons, Inc.