Cognitive Psychology, Fifth Edition, Robert J. Sternberg Chapter 6 Chapter 6: Memory Processes

Cognitive Psychology, Fifth Edition, Robert J. SternbergChapter 6

Chapter 6: Memory Processes


Memory Processes


Encoding Processes

• Creating an acoustic code– What it sounds like

• Creating a semantic code– What it means

• Creating a visual code– What it looks like


Encoding Types and STM

• Type of code may rely on type of task

• STM refers to memory that is held temporarily

• Evidence exists for a variety of encoding types in STM


Evidence for Acoustic Encoding in STM

• Conrad (1964)– Visually present a series of letters briefly

– Immediately write the letters viewed once series is complete (Try it - Starts on next click)


Conrad (1964)

• You Viewed B C F M N P N S T V

• What errors did you make? – F for S– B for V– P for B

• Not visual errors (e.g., E for F, O for Q, R for P)

• Thus, items acoustically even though stimuli were presented visually


Shulman (1970)

• Evidence for semantic encoding in STM

• Participants viewed 10-word lists

• Given a recognition test using visually represented "probe words" which were either: – Homonyms - e.g. "bawl" for "ball" – Synonyms - e.g. "talk" for "speak" or– Identical to the original word


Shulman (1970) Results

• The Homonym and Synonym probes produced similar error rates - suggesting that an equal amount of acoustic and semantic processing must be taking place– Homonyms - e.g. "bawl" for "ball" – Synonyms - e.g. "talk" for "speak" – Identical to the original word


Posner & Keele (1967)

• Evidence for visual encoding in STM– Letter matching task

– Two letters separated by brief interval

– Participant had to indicate if same letter• A-a Yes

• A-A Yes

• A-M No

– Measure reaction time


Posner & Keele (1967) Results

• If letters were the same visually (a-a) participants were faster than if the letters were not the same visually (A-a)

• Results indicate that visual code was also present for STM


Encoding Types & LTM

• Type of code may rely on type of task

• LTM refers to memory that may be held permanently

• Evidence exists for a variety of encoding types for LTM


Semantic Encoding in LTM

• Grossman & Eagle (1970)– Study 41 different words– Given recognition test after delay– 9 of the distractors were semantically

related to words on list– 9 of the distractors were not – False alarms for each type: 1.83 of

synonyms, but only 1.05 of unrelated


Visual Encoding in LTM• Frost (1972)

– Participants studied 16 drawings– Manipulated visual orientation and semantic

category– After a delay, participants were asked if they had

studied an object with the same name as the test object

– Reaction time was measured– Participants responded faster to identical drawings

than drawings in a different orientation– This result indicates visual encoding occurred


Acoustic Encoding in LTM

• Evidence of very long-term memory for songs

• Rubin (1977)

• Participants recall more of the text when provided with the melody of a well-learned song ("Star Spangled Banner") than when given no cue


Transfer from STM to LTM

• Consolidation– Integrating new information into stored

information

• Disruption of consolidation is studied in amnesiacs– ECT patients (Squire)


Metamemory

• Knowing what you know

• Knowing how your memory works

• Being able to assess your own memory

• Young children lack metamemory skills


Principles to Strengthen Memory

• Elaborative rehearsal is better than maintenance rehearsal

• Distributed practice is better than massed practice – “Spacing effect”

• Organizing information enhances memory


What causes the spacing effect?

• Multiple encoding contexts theory– Multiple study sessions lead to multiple types

of encoding, thus more possibility of matching during test conditions

• REM Theory– The more REM sessions following study

sessions, the more consolidation that occurs


Mnemonic Devices to Aid Memory

• Categorical clustering

• Interactive images

• Pegword system

• Method of loci

• Acronyms

• Acrostics

• Keyword system


Which Mnemonic is the Best?•Roediger (1980)

[Insert Table 6.2]


Prospective Memory

• The ability to remember a future intention– Buying bread on your way home from

work

– Going to the dentist on Wednesday

• Retrospective memory is memory of the past


Retrieval Processes

• Getting information back out

• Multiple processes can be used to enhance retrieval

• Different strategies are used for short term storage and long term storage

• Matching the type of processes done during encoding with the type of processes done at retrieval increases success


Retrieval from STM

• Is the search serial or parallel?– Serial indicates one by one search– Parallel means all items are processed at once

• Is the search exhaustive or self-terminating?– Exhaustive indicates that all items in the set are

examined– Self-terminating means that after target is found

the search stops


Studying Searching in STM

• Saul Sternberg (1967) • Memorize a set of

numbers (6,3,8,2,7) • Shown a probe digit• Participant must

indicate if the probe was in the set

• Time to respond is measured

6,5,8,2,7

2

Yes


Sternberg (1967)

• 3 critical factors manipulated– How many items were in the set the

participants had to memorize

– Whether the probe was in the list

– The probe’s location in the set


Sternberg (1967)

•Possible Result Patterns – A represents parallel

processing

– B illustrates serial processing

– C illustrates exhaustive serial processing

– D illustrates self-terminating serial processing


Sternberg’s Conclusion

• A serial exhaustive model

• But….– Corcoran (1971) proposed that a parallel model

could also explain the pattern found– Townsend (1971) stated it was mathematically

impossible to distinguish parallel from serial– Thus, both models still exist


Retrieval from LTM

• The types of cues you use to retrieve may affect what you can retrieve…– Free recall vs Categorized recall

– Study random list or an organized list

• What is the impact on memory?


Bower, Clark, Lesgold, and Winzenz (1969)

Randomized list

Naples World Italy Americas

Montreal Bristol Washington Ottowa

Orlando England Europe Dallas

Liverpool Winnipeg Rome USA

London Florence CanadaOrganized list

World

Europe Americas

England Italy USA Canada

London Rome Washington Ottowa

Liverpool Florence Dallas Montreal

Bristol Naples Orlando Winnipeg


Bower & Associates (1969)

• Participants remembered 65% of the organized list, only 19% of the random list

• Thus, Organization helps memory retrieval


Chechile (2004)

• Manipulated time to retrieve and probablility of retrieval– Little time, fewer words recalled

– More time, more words recalled


If You Cannot Retrieve from LTM…

• Has the memory disappeared?

• Is the memory available but not accessible?


Evidence Supporting “Still There” Theory Nelson (1971)

Paired associate List43-house67-dog38-dress77-sissors

Cued recall test43- ________67- ________

Two week delay

Subjects recalled 75% of items on list

But focus was on 25% they forgot.


Nelson (1971) Critical ManipulationIf participants forgot “38-dress” and “77-sissors” then participants relearned either same pairs or changed pairs

25%

“forgotten” Relearned Results

Same38-dress 77-sissors

38-dress 77-sissors

Changed38-dress 77-sissors

38-apple 77-kettle

The better performance of participants in the same condition indicate that there was some memory left for “forgotten” items. Otherwise both groups would remember the same amount.

78%

43%


Theories about Forgetting

• Decay theory– Memory is weakened with disuse

– Simply passage of time…

• Interference theory – Proactive: old memories interfere with

recall of new information

– Retroactive: new memories interfere with recall of old information


Interference versus Decay in STM

• Brown-Peterson Paradigm– Participants were given 3 consonants to try

to remember (e.g., FRL)

– Participants were then given a 3 digit number (294) & asked to count backwards by threes (e.g., 291, 288, 285)

– After varying delays (3-18 seconds) participants were asked to recall the 3 letters


Brown-Peterson results (1959)

Trigrams were forgotten by 18 seconds due to retroactive interference of counting backwards


Proactive Interference in STM

•Keppel & Underwood (1962)– Replicated the Peterson & Peterson Task varying the time delay

to recall– Analysis was done by trial number (1st trial, 2nd trial, 3rd trial,

etc.)– Found support for proactive interference


Retroactive Interference from LTM

Experimental group

Learn List A Learn List B Delay Test for Memory A

Control

group

Learn List A ------------ Delay Test for Memory A

The experimental group will remember less material from the tested list A compared to the control group

Information learned afterwards interferes with retrieval of List A.


Proactive Interference from LTM

Experimental group

Learn List A Learn List B Delay Test for Memory B

Control

group

No study Learn List B Delay Test for Memory B

The experimental group remembers less material from the tested list B than the control group

Information previously learned (list A) interferes with retrieval of List B


Let’s Test Your LTM!

• You will see several words, one at a time

• Do whatever you can to try and remember as many of the words as you can

• At the end of the list, try to recall as many words as you can


BED


CLOCK


DREAM


NIGHT


TURN


MATTRESS


SNOOZE


NOD


TIRED


NIGHT


ARTICHOKE


INSOMNIA


REST


TOSS


NIGHT


ALARM


NAP


SNORE


PILLOW


Write down the words you saw


Here are the words in the order viewed

BED

CLOCK

DREAM

NIGHT

TURN

MATTRESS

SNOOZE

NOD

TIRED

NIGHT

ARTICHOKE

INSOMNIA

REST

TOSS

NIGHT

ALARM

NAP

SNORE

PILLOW

Did you recall? Explanation

Bed? Clock? Primacy EffectSnore? Pillow? Recency Effect

Spacing EffectNight?

Artichoke? Distinctiveness

Toss? Toss & Turn?

Clustering

Sleep? False Memory


Serial Position Curve


Autobiographical Memory

• Memory of personal history

• Constructive in nature


Constructive Nature of LTM

• Bartlett (1932) was the first to demonstrate distortions for prose– Read stories about Native Americans

– Subjects were good at recalling “gist”gist” information

– Omission of detail was systematic• Tended to omit information that did not

make sense to the participants


Constructive Nature of LTM

• Prior experience influences how we recall information

• Having retrieval cues can help us recall more information, but cues can also lead to errors


Nancy arrived at the cocktail party. She looked around the room to see who was there. She went to talk with her professor. She felt she had to talk to him but was a little nervous about just what to say. A group of people started to play charades. Nancy went over and had some refreshments. The hors d’oevres were good but she was interested in talking to the rest of the people at the party. After a while, she decided she’d had enough and left the party.

Some participants also heard that passage, but w/ this theme:

Nancy woke up feeling sick and she wondered if she really were pregnant. How could she tell the professor she had been seeing? And the money was another problem.

Participants were then asked to recall as much about the story as they could

Owens, Bower and Black (1979)


Owens, Bower and Black (1979) Results

Theme No Theme

Studied Propositions

29.2 20.3

Inferred Propositions

15.2 3.7

The “theme” offered some background information and some retrieval cues, which increased recall. However, the background info also led to more intrusions (memory for information not present), such as “The professor got Nancy pregnant.”


Memory Distortion

• Simply recalling may distort your memory

• Simple suggestion may distort your memory

• Memory is constructive in nature


Schacter’s “Seven Sins of Memory”1. Memories are transient (fade with time)

2. We do not remember what we do not pay attention to

3. Our memories can be temporarily blocked

4. We can misattribute the source of memory

5. We are suggestible in our memories

6. We can show memory distortion (bias)

7. We often fail to forget the things we would like not to recall (persistence of memory)


Eyewitness memory

• The single greatest cause of wrongful convictions nationwide, playing a role in more than 75% of convictions overturned through DNA testing.

• http://www.innocenceproject.org/


Loftus & Palmer (1974)

• Participants were all shown the same video of an accident between two cars

• Some subjects asked: “How fast were the cars going when they smashed into each other?”

• Others were asked: “How fast were the cars going when they hit each other?”


Loftus & Palmer (1974)

Word Used Average Speed Estimated

Smashed 41 m.p.h.

Collided 39 m.p.h.

Bumped 38 m.p.h.

Hit 34 m.p.h.

Contacted 32 m.p.h.

“How fast were the cars going when they ________ into each other?”


Problems with Lineups

• Assumption that perpetrator is in lineup

• Distractor selection is also important

• Police behavior may also influence


Children’s Eyewitness Memory

• Be wary of repeated questioning

• Leading questions may distort memory

• Younger children are more suggestible


False Memories / Memory Illusions

• Roediger & McDermott (1995)– Present a list of associated words, missing one

“target” word (e.g., tired, bed, night, dream, etc., but not SLEEP)

– With immediate recall, participants tend to recall the non-presented target item

– More importantly, when asked whether they “remember” or “know” the word was on the list, they report an actual memory for the item


False Memory cont’d

• Garry, Manning, Loftus & Sherman (1996)– Participants complete Life Events Inventory

(LEI)– Then are led through imagination exercises– Fill out LEI again

• The results show that when participants imagine events that they said did not happen to them, they are more likely to say they did happen to them


Repressed or Recovered Memories of Abuse

• A person remembers now that 20 years ago, someone sexually abused them

• Traumatic memory was previously repressed, but was recovered (often) under hypnosis in therapy

• Validity of recovered memories?

• Empirical evidence for Freudian repression?


Can Painful Abuse Memories be Repressed?

• Skeptics argue that repression (or in some cases dissociation) of sexual memories is a concept without any scientific merit

• If repression does not exist, there can be no such thing as a recovered repressed memory; rather, a recovered memory of abuse can only be a false memory of abuse


False Memory vs. Repressed Memory Issue

• Evidence for suggested false memory is not automatically evidence against repressed-recovered memories, and vise versa


No Consensus on the Issue• Results vary dependent upon characteristics sample

(volunteers, children, child services, adult recall, etc.)– Some abuse memories are not traumatic, and thus are

presumably not repressed, rather they may be forgotten, like any memory

• Post-traumatic stress syndrome may also occur– One symptom is recurrent, intrusive thoughts about the

traumatic incident—this is the opposite of repression

• Some may handle memory of sexual abuse by blocking out of mind either by repression or dissociation


Flashbulb Memories

• Some researchers propose that events that are particularly surprising or arousing will yield flashbulb memories

• Where were you when the…– Challenger explosion occurred?– OJ verdict was read?– JFK was assassinated?– Bombing of the twin towers?


Flashbulb Memories

• Some research proposes good memory for– Place where you learned of information– What you were doing when you heard it

– Where you heard the information from– Emotions in self and others– The aftermath


Emotion and Memory

• There is a strong relationship (.90) between the emotionality and vividness of memory – This does not mean that the memory is

accurate

• Emotional events seem to be less resistant to forgetting over time… – Perhaps they are perceived better– Perhaps we think about them more


Flashbulb Memory Results

Neisser and Harsch (1992)– Tested immediate memory for Shuttle

Explosion, and then tested it again 3 years later

– There was little agreement with the two “memories” despite the confidence of the participants


Encoding Specificity

• Memory is improved when information available at encoding is also available at retrieval


Amabile & Rovee-Collier (1991)

• The match between encoding and test for babies is very important

• 3 & 6 month old infants were taught in crib with a particular bumper background to kick to move the mobile


Amabile & Rovee-Collier (1991)

• Infants kicked more strongly in the same context

• However, you can teach infants in multiple contexts to weaken the encoding specificity


Encoding Specificity Tulving & Thompson (1973)

1st Study list: Learn target words in capital letters

Cue Target

head LIGHT

grasp BABY

2nd Free association: Generate 6 words for each word presented

Word Possible Generations

dark light, black, room….

infant sleeping, bottle, baby….


3rd Recognition Test: Circle any generated words that were in the study list in capital letters

Word Possible Generations dark light, black, room…. infant sleeping, bottle, baby….

4th Recall: Recall the words from the study list in capital letters, using these cues that they were studied with

Word Possible Generations grasp ________ head ________


Free AssociationRecognition test

Study ListRecall test

Percentage of

words

Recalled /

Recognized

0

100

50

Tulving & Thompson (1973) Results

They recalled more than they

recognized!


Encoding Specificity

• Tulving (1983)– People encode the context with the target

material• Physical match (class, diving, smell)

• Emotional match (happy, depressed)

• Understanding match (childhood amnesia, under the influence of drugs match)


Memory Development--Kail

• Asked participants aged 6 to 21 to do mental addition to a memory search

• Found age-related increases in the amount of information that could be held in memory

• Is it the capacity that increases or the ability to use the capacity?


Kail & Hall (1999)

• 12 boys and 12 girls at ages 8, 9, 10, 11, and 12 years

• Given simple addition and subtraction word problems

– “Nancy has 6 marbles. Eve has 3 marbles. How many marbles does Nancy need to give away to have as many as Eve?”


Results

• Both domain-specific and general information-processing skills contribute to children's success on word problems

• Thus, older children holding larger and more complex bits of information


Metamemory Knowledge in Children

• Young children– Underuse strategies

– Have little connection between memory awareness and memory strategies

– Less likely to spontaneously use memory strategies


Appel, Cooper, McCarrell, SimsKnight, Yussen & Flavell (1972)

• Preschoolers (4 yrs old), First Graders (7 yrs old) and fifth graders (11 yrs old)

• Given either a “Look” or a “Remember” task

• 9-15 Pictures of vehicles, clothes, food were displayed

• Children were observed to see if they showed any behaviors indicating a memory strategy during the “look and memory” task


Appel et al. Results

• If told to “look”, no one used a memory strategy

• If told to “remember”, older children used a strategy to help, preschoolers did not

• Older children remembered more


Cognitive Monitoring

• What you know and what you do not know– Flavell, Friedrichs & Hoyt (1970)– Preschool and elementary children asked to

study a set of items until they were sure they could recall them perfectly…

– When tested, elementary children could recall pretty well, the preschool children could not.


Memory in Adulthood

• Cohen (1992) – Older university students received better

coursework grades than younger students

– However, if timed recall was required, they did less well.

– Most age decline can be compensated for by expertise

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Cognitive Psychology, Fifth Edition, Robert J. Sternberg Chapter 6 Chapter 6: Memory Processes