PSY 368 Human Memory

PSY 368 Human MemoryMemory Processing

Announcements

• Craik and Lockhart (1972) download, read, and answer focus questions, due Monday Feb 27

• Processing views homework due Web Feb 29

Structural Model

• Memory composed of storage structures that hold memories for a period of time • Sensory memory• Short-term memory (STM)• Long-term memory (LTM)

• Memory is also made up of Processes

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Structure Processes

• We’ve talked about things like rehearsal and elaboration as being important for moving information between the different memory systems• Processing views• Focus on what gets done to the information• e.g., rote rehearsal versus elaborative rehearsal

• Need to look at both learning (encoding) and at test (retrieval)

• Structural (Modal) views• Properties of memorized information (e.g., how long

it lasts) come from where it is stored (Sensor, STM, or LTM)• E.g., the longer an item is held in STM, the more likely it

would get into LTM (and be stored more ‘durably’)

• Processing views• Encoding (focus on ‘getting things into memory’)• Level of processing

• Interaction of Encoding & Retrieval (focus on ‘getting things in and out of memory’)• Transfer-appropriate processing

• Importance of context

• Encoding specificity principle

Structure Processes

Demo

For each item below with a ! next to it, indicate if it is alive.For each item below with a * next to it, indicate if it has an “e.”

! flag! kite* house* jail! spider* snake* picture! duck

* flame

! bottle

! tree* happy

* storm

! ball! class* horse

! zebra* test! window* hair* dream! rock! table* fountain

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• Task:• Participants had to repeat nonsense

syllables either once or many times.

• Only half of the participants were warned of an upcoming recall test.

Mechanic (1964)

• Conclusion:• Rehearsal led to better recall

• Knowing that there is a test coming prompted additional processing in the intentional learning group.

• Results:

Rehearsal

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• Task:• Participants were asked to remember numbers over a

delay.• During the delay, they had to read out words (in time

with tones every 2 sec.)• Some words were repeated only once during the

delay; others were repeated many times.• Participants then recalled the numbers followed by a

surprise recall (or recognition) test for the words.

Glenberg, Smith, and Green (1977)

• Results:• Having nine times as many repetitions only increased

recall by 1.5% (9% for recognition), suggesting that simple maintenance rehearsal doesn’t help long-term recall much.

Rehearsal

• Finding:• Maintenance didn’t help

• Stimuli:• Already known words

• Rationale:• The recall test relied on

meaningful links between the known words (already in LTM), which depend on deeper, semantic features

• Finding:• Maintenance did help in one

condition

• Stimuli:• Unfamiliar stimuli that need to

be learned from scratch

• Rationale:• Repeating unfamiliar stimuli

with no natural links between them boosts their representation in phonological LTM

Glenberg, et al. (1977)Mechanic (1964)

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Rehearsal

DemoFor each item below with a ! next to it, indicate if it is alive.For each item below with a * next to it, indicate if it has an “e.”

! flag * flame ! zebra! kite ! bottle * test* house ! tree ! window* jail * happy * hair! spider * storm* dream* snake ! ball ! rock* picture ! class ! table! duck * horse * fountain

Write down as many of the words as you can remember.• Count up how many were from the “with an e” and

how many from “is it alive?”

• Emphasizes memory processes rather than structures• Based on the idea that the strength of a memory

trace is determined by how the original info was processed• Incoming stimuli pass through a series of analyzing

mechanisms• Memory traces are a product of how stimuli are

analyzed • Strength of trace depends on:• Attention paid to stimulus• Depth of processing carried out• Connections with existing knowledge

Levels of Processing

Level of Processing

Craik & Lockhart (1972)• Argue against structural/modal models of memory • Features that distinguish stores are not clear

• Distinguished elaborative and maintenance rehearsal• Elaborative - rehearse item using its meaning (better memory)

• Maintenance - rehearse items by repeating it over and over• Keep in STM/WM, but doesn’t get it into LTM

• Importance of Incidental learning• If participants know that they’ll be tested for memory

they may engage in different techniques/strategies

Level of Processing

Craik & Lockhart (1972)• Considered level of processing at study to be more

important for memory than intent to learn• Levels of processing = how “deeply” the item is

processed• The depth of processing helps determine the

durability in LTM.Level of Processing

Example

1) Visual Form “DOG” includes the letters D, O, and G

2) Phonology Rhymes with FOG

3) Semantics (Meaning)

A four-legged pet that often chases cats and chews on bones

SHALLOW

DEEP

Craik and Tulving (1975)


Task:• Participants viewed words and were asked to make

three different types of judgments:• Visual processing (e.g. “Is LOG in upper case?” Y/N)• Phonological (e.g. “Does DOG rhyme with LOG?” Y/N)• Semantic (e.g. “Does DOG fit in the sentence: ‘The ___

chased the cat’?” Y/N)• Finally, participants were asked to recognize the

words they had seen before in a surprise test including both old and new words.


Craik and Tulving (1975)Results:• Words that were more deeply processed were more

easily recognized -- particularly for questions with a “YES” response. Conclusions:

• Deeper processed items had stronger memory traces than shallow processed items.

• “Yes” responses were better recalled because these items are better integrated with the encoding question.

Hyde and Jenkins (1973)


• Auditory study of words with incidental and intentional tasks• Half knew they be tested later• Half didn’t know about a later test• Control group: no instruction, but told about later

memory test

• Task: studied 24 common words, auditory presentation, free recall task

(1) Look for “e” and “g” in word

(2) Identify part of speech

(3) Rate how common the word is

(4) Rate pleasantness of word

SHALLOW

DEEP


Hyde and Jenkins (1973)

Results

•Depth of processing effect

•Incidental: the deeper the level of processing, the more words recalled.

•Incidental: recall on the pleasantness task was as good as control group recall.


Craik and Watkins (1973)

• Tested the idea that rehearsal doesn't really help memory.

• Had people rehearse a word until another word that started with the same letter occurred in the list.

• Task: report the last word that began with that letter.

• Rehearse words that start with "g”Operational definition of rehearsal time: the number of

intervening words

garden = 0 grain = 3 Rehearsal time ranged from 0 to 12.

daughter, oil, rifle, garden, grain, table, anchor, football, giraffe


Craik and Watkins (1973)

• Tested the idea that rehearsal doesn't really help memory.

• Had people rehearse a word until another word that started with the same letter occurred in the list.

• Task: report the last word that began with that letter.

• 10 minutes after the final trial, subjects got a surprise recall test: report as many of the words that began with "g”.

daughter, oil, rifle, garden, grain, table, anchor, football, giraffeResults:

• Recall of an item was not correlated with how long it had been rehearsed.

• garden remembered just as well as grain

Criticisms:• It is difficult to operationally define depth of

processing.• Can’t use processing speed to define it.• Different levels of processing can occur

simultaneously, rather than in series, making them hard to separate in a task.

• Deeper processing does not always lead to better performance.

• Ignores effects of retrieval task


Morris, Bransford, and Franks (1977)• Focus on processing at study (encoding)

AND test (retrieval)• If processing at study and test match, better

memory• Levels of Processing effect for tasks that use

a lot of semantic processing (like free recall)

Transfer-appropriate processing

Morris, Bransford, and Franks (1977)• Task: • Participants made either a phonological or semantic

judgment about each item on a word list.

• Study: eagle (yes/no fits clue)• Deep - The ____ is the US national bird.• Shallow - rhymes with legal

• The learning was incidental: participants were not told that they would have to later recall the words.• This constrains (limits) the learning strategies

used.


Morris, Bransford, and Franks (1977)• Task: • The final test was either:• A standard recognition test for the learned words.• A rhyming recognition test for learned words• e.g., Was a word presented that rhymed with

“regal”?



Encoding: Recognition test:

Rhyming test:

Does ____ rhyme with legal? (eagle)

63% 49%

Does ____ have feathers? (eagle)

84% 33%

Morris, Bransford, and Franks (1977)

• Results:• Standard recognition test: Deeper processing led to better

performance.• Rhyming recognition test: The shallower rhyme-based

encoding task led to better performance because it matched the demands of the testing situation.


Encoding: Recognition test:

Rhyming test:

Does ____ rhyme with legal? (eagle)

63% 49%

Does ____ have feathers? (eagle)

84% 33%

Morris, Bransford, and Franks (1977)

• Conclusion:• The take-home message is that when the processing at encoding matches

the processing at retrieval, performance will be better.• It only makes sense to talk about a learning method’s efficiency in the

context of the type of final test.

Abernathy (1940)

• Found that students tested in the same classroom in which they learned did better on tests than students tested in a different classroom.

• Context matters• Interaction of encoding and retrieval• Context at study (e.g., cues, environment,

processing, etc.) and context at retrieval• Better memory if the contexts match

Context Effects

Godden and Baddeley (1975)

• Used subjects from a SCUBA diving club in gear

Context Effects

Study Condition

Test Condition

On Land Underwater

On Land Match Mismatch

Underwater

Mismatch Match

Godden and Baddeley (1975)

• Used subjects from a SCUBA diving club in gear

Context Effects

Results:

• Recall was better when study environment and test environment matched, regardless of whether it was on land or under water.

Results

• For items learned during intoxication, there is a large difference in performance at recall

• For items learned during sober, the difference is smaller

Context Effects

(errors) Study Condition

Test Condition

sober drunk

sober 1.25 4.58

drunk 2.25 2.50

• Also called state-dependent memory• Match between study and test state/context predicts

memory performance

• Goodwin et al. (1969) alcohol study:

• Some subjects received 10 oz of 80-proof vodka at study, at test, or both

• For emotional state: mood-dependent memory

• Bartlett & Santrock (1979) mood study:

• happy or neutral mood at study

• happy or neutral mood at test

• Recall was better when moods matched

• This effect is not always replicated -- one important factor is to produce a strong, sincere, mood.

Context Effects

Tulving (1972, 1983)

•The recollection of an event or a certain aspect of it depends on the interaction between the properties of the encoded event and the properties of the retrieval information.• What is stored determines what retrieval cues are

effective in providing access to what is stored.• Match between cues at study and test results in

better memory• The most effective retrieval cues will be the ones you

used during the original learning.

Encoding Specificity Principle

Thompson and Tulving (1970)• Examined effectiveness of cue• Had people learn lists of strong or weak

associates.• Strong vs. weak cues (“flower”)• Strong: bloom• Weak: fruit

• Study: no cue vs. weak cue• Test: no cue, weak cue, or strong cue



Thompson and Tulving (1970)

• Thompson and Tulving showed that this can be reversed if you change the study context.

• The best retrieval cue for a word like “flower” would be a strong associate like “bloom.” “fruit” is weakly associated to “flower,” and would be unlikely to pull it out.

Brief Summary

• Where something is stored isn’t everything. How you encode and retrieve the information is critical.

• Encoding:• Levels of processing

• Encoding + Retrieval• Context effects (environment, mood)• Transfer-appropriate processing• Encoding specificity principle (cues)

Documents

PSY 368 Human Memory