Lecture 7 memory processes

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Lecture 7
LONG-TERM MEMORY PROCESSES: ENCODING, RETRIEVAL
AND CONSOLIDATION
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TODAY
o Factors that aid encoding
o Retrieval techniques
o Neural representation
o Application: studying
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GETTING INFORMATION INTO LTM
o Encoding : Acquiring information and transforming it into memory
 Vs. Coding: form of information representation
 Coding is the process
o Retrieval: Transferring information from LTM to working memory
 Retrieval is getting info back out of LTM
 In order to retrieve something, we needed to have encoded it in the first
place
o Rehearsal
 1. Maintenance rehearsal
 Repetition maintains info but does not transfer it to LTM
o phone number, directions
o not very effective for later
 Repeating doesn’t transfer to LTM. It keeps in short term memory
or working memory long enough to achieve your goal. But you
need to do something else to get into LTM
 Maintenance rehearsal example: when someone tells you the
directions
 2. Elaborative rehearsal
 Meanings and connections to transfer info to LTM
o PIN number, passwords
o More effective
 Elaborative rehearsal is really what is going to transfer info to
LTM
 Its any way of giving meaning or making a connection between the
information you want to encode and something else.
 Any meaning and connection that you give to the information is
going to help it get into LTM
 Passwords, pin numbers, if it’s truly random you won’t be able to
remember it, so you have to come up with a strategy to remember
it.
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LEVELS OF PROCESSING THEORY
o Memory depends on nature of encoding
 Depth of processing
 Shallow processing
o Little attention to meaning
o Focus on physical features
o Poor memory
o Maintenance rehearsal = shallow processing
 It wont get us anywhere to moving info to LTM
 Deep processing
o Close attention to meaning
o Better memory
o Elaborative rehearsal = deep processing
o Craik and Tulving (1975)
 IV: Between subject- level of processing
 1. Physical features = shallow processing
 2. Rhyming = deeper processing
 3. Fill in the blanks = deepest processing
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subjects were shown words and asked certain questions about the word.
 Ie is the word in capital letters or not ( shallow processing)
 In the nest question, does the word rhyme with another word
o This is thought to be more of a deep processing because
you have to make a connection but its still not looking at
meaning so its depth is limited.
 Next question, I saw a (blank) on the street
Group 3 is the deep processing
 Because in order to determine if the word fits in the sentence, you
have to understand what it means.
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Results: Deeper processing = Better recall
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Paying attention to the physical feature group 1 didn’t perform
very well = shallow processing
At 50 % correct is the medium processing
The best performance is to determine the meaning group = deep
processing
The deeper the processing, the better the recall of the info will be
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BEWARE OF CIRCULAR REASONING !!!
o Which task causes deeper processing?
 Using a word in a sentence
 Deciding how useful an object might be on a desert island.
 Maybe bc its about survival
 Knowing the meaning of the word is deep processing
o Depth of processing has not been defined independently of memory performance
 Therefore, this is circular reasoning
 The way we would test this is by saying which one results in
greater recall
 But if we do this, it results in circular reasoning
 Inverse probability error
 You can see if words rhyme without knowing the meaning of the
word at all.
 It is a reasonable case to make that rhyming words is a deeper
processing than paying attention to the case of the word.
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TYPES OF DEEP PROCESSING
o 1. Visual imagery
o 2. Self-reference effect
o 3. Generation effect
o 4. Organizing information
o 5. Survival processing
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VISUAL IMAGERY
o Bower & Winzenz (1970)
 Paired-associate learning
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There is no support for visual learning. It seems that visual imagery
benefits us all.
If you can make an image in your head, it increases the probability of
retrieving the information later.
A pair of words were shown to participants really briefly for 5 seconds.
Half of the group were told to silently repeat the words to themselves
The other half were told to make a visual picture
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Results: Visual Imagery = better recall
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Visual imagery group is performing 3x better than the repetition group
Creating images in your head can be really beneficial for your LTM
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SELF-REFERENCE EFFECT
o Rogers et al. (1977)
 IV: Encoding
 Physical (case)
 Rhyme (snappy)
 Meaning (upbeat)
 Describes you
 DV: Recall
 Results: Better recall when relating words to yourself
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The more you can relate info to yourself, the better you are at recalling it.
Self-reference processing is better than deep processing (meaning)
GENERATION EFFECT
o Slameka and Graf (1978)
 IV:
 Read: King-Crown ; Horse-Saddle ; Lamp-Shade
 Create: King-Cr___ ; Horse-Sa___ ; Lamp-Sh___;
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Results: Create = Recall increased 28%
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Active creation > Passive reception
 Coming up with the information on your own.
 In the second condition, asked to fill in the words
 Results: when they were asked to recall the words, actually
creating the second pair increased recall by almost 30%
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ORGANIZING INFORMATION
o Bower et al. (1969)
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Recall = 73 organized vs. random 21 words
Creates a way for us to organize the thoughts in our minds which can lead
to better recall.
o Use when studying !
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SURVIVAL PROCESSING
o Adaptive memory
 Natural selection shaped memory processes
 Helped solve problems of survival
o Food (e.g. foraging adaptation theory)
o Navigation
o Reproduction
o Social exchange
o Kin
 Adaptive significance = improve memory
o When we’re considering if information is going to help us survive, it’s going to be
encoded. This is about human evolution over time
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o Nairne et al. (2007)
 IV: Rating context (survival, moving, pleasantness)
 DV: Recall
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FORAGING ADAPTATION THOERY
o Hunting mobile prey and gathering immobile resources have different
computational requirements
o Therefore, we should observe sex differences in foraging-relevant cognitive
functions that mirror the ancestral sexual division of foraging labour
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Hunting
 Prey pursued over erratic courses, unfamiliar environments
 Spoils should be carried home directly
 Male advantage
 Gathering- because typically provided infant care ( the majority of itbreast feeding & pregnancy restrict women’s movements across
territories, etc)
 Stationary, vary in quality/temporal availability
 Must register and store multiple locations within well-known
constrained environments
 Female advantage
o This could be a good written question for the test: explain foraging adaptation
theory- including the supporting evidence
 Hunting:
 Prey pursed over erratic courses, unfamiliar environments
 Gathering:
 Women had responsibilities that kept them more stationary
 Stationary, vary in quality/temporal availability
 Must register and store multiple locations within a well-known
constrained environments
 Female advantage
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o New et al. (2007)
 6 visits to farmer markets
 90 stalls
 “farmer’s market research”
 Participants visit 6 stalls and sample food item
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The research looked at how men and women perform in a task that
requires landmark navigation
o We would think women are better.
Given a food item to taste and then rate it on different categories.
At the end, they were taken to the center of the market to a
pointing device which had an arm that could move around in a
complete circle.
The participants had to move the pointer to for example, the
strawberry stall.
They had to aim the pointer at all the stalls they went to
So here there was an advantage for the female participants.
Women were more accurate at pointing to these stationary food
items
BUT it depended on the caloric item of the food
The MORE caloic dense an item was, the more accurately people
pointed to its location
o Ie. There was a greater accuracy at pointing to the location
of honey than that of lettuce.
After sample, taken to a pointing device in the center of the market
 A wooden pointer was fixed at the center of the circle and could be
spun freely.
Aim the pointer at each of the 6 food items.
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Results:
 Women > Men
o 9 degrees, 27%
 Food type
o Higher > Lower caloric density
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All the fruits come from different regions/ territories
We actually learn in an implicit way, where we get the most enjoyment for
food.
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OTHER FACTORS THAT AID ENCODING
o Retrieval practice
 E.g. Self-test, Flash cards
o Roediger & Karpicke (2006)
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This is what you do when you make up your own flash cards or when you
do practice tests.
You’re strengthening those connections everytime you recall it to working
memory
Testing yourself vs. rereading notes.
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Results: Practicing retrieval = Better recall
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If you have a test in 5 minutes, best thing you can do is reread
material
If the test is 2 days or a week later, it is better if you have tried to
retrieve that information already in the past.
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So doing a practice test is more advantageous than rereading the
material.
RETRIEVING INFORMATION FROM LTM
o Retrieval: Process of transferring information from LTM back into Working
Memory (consciousness)
 Most of our failures of memory are failures to retrieve
o Recall:
 Free recall
 Remember stimuli
o Cued-recall: Cue presented to aid recall
 Increased performance over free-recall
 Retrieval cues more effective when created by the person who uses them
o Multiple choice exam: Ability to recognize
o Short answer questions are more about free recall, it requires that the information
has been elaborated and deep processed.
o Mantyla (1986)
 504 nouns
 Banana
 Freedom
 Tree
 Generate 3 associated words (cues)
 DV: Cued recall
 Creator-specific effects
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Subjects were shown a long list of words- all nouns (means they could be
described by adjectives)
The Cues were then shown back to half the subjects, and the other half of
the subjects got someone else’s cues
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When you come up with the cues yourself, you’re better able to recall the
initial word
Control group: they were given the list of the cues and were asked which
words they related to
Its not just about the strength of the cue, but rather whether the cue came
from your own mind.
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CONTEXT-DEPENDENT MEMORY
o 1. Encoding specificity
 Environment
 E.g. location
o 2. State-dependent learning
 Internal state
 E.g. mood
o 3. Transfer-appropriate learning
 Task
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ENCODING SPECIFICITY
o We learn information together with its context
o Baddeley’s (1975) “Diving Experiment”
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STATE-DEPENDENT LEARNING
o Learning is associated with a particular internal state
 Mood:
 Mood-congruent memory
 Bipolar disorder
 Pain
 Warm vs. cold water
 Substances
 Caffeine
 Ritalin
 Alcohol*
o Eich & Metcalfe (1989)
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TRANSFER-APPROPRIATE PROCESSING
o Morris et al. (1977)
 Meaning:
 The ____ had a silver engine.
 Rhyming:
 _____rhymes with soda.
“TRAIN”
YES
“TRAIN”
NO
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Recall: Does “RAIN” rhyme with target word?
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Level of processing?
CONSOLIDATION
o Transforms new memories from fragile state to more permanent state
o 2 overlapping processes
 1. Synaptic consolidation
 Occurs at synapses
 Happens rapidly
 2. Systems Consolidation
 Gradual reorganization of circuits in brain
 Slower
o Consolidation takes time
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Muller and Pilzecker (1900)
 2 lists of non-sense syllables
 Immediate 2nd list disrupted consolidation
INFORMATION STORAGE AT THE SYNAPSE
o Hebb (1948)
 Learning/memory represented by physiological changes at synapse
 Repetition = Strengthen synapse
 Structural changes
 Greater transmitter release
 Increased firing
 Long-term potentiation
 Strengthening of the synapses between 2 simultaneously-activated
neurons
 Fires together, wires together
o Long-term potentiation (LTP)
 Enhanced firing of neurons after repeated stimulation
 Structural changes and enhanced responding
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CONSOLIDATION
o Standard model of consolidation
 Retrieval depends on hippocampus during consolidation;
 After consolidation hippocampus is no longer needed
 Reactivation: Hippocampus replays neural activity associated with
memory
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THE FRAGILITY OF NEW MEMORIES
o Retrograde amnesia: Loss of memory for events prior to the trauma
o Graded amnesia: Memory for recent events is more fragile than for remote events
o Patient AF
 15 year old male
 Head trauma
 Retrograde amnesia 2 yrs prior to injury
o Patient CDA
 20 year old male
 Retrograde amnesia 2 years prior to injury
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CONSOLIDATION
o Multiple trace hypothesis
 Proposes role of hippocampus in episodic retrieval
 Hippocampus activated during retrieval of recent & remote memories
 But hippocampal response can change over time (Viskontas and
coworkers, 2009)
o Hippocampal responses decrease over time
 When memories are semanticized
 Not when they remain episodic
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CONSOLIDATION AND SLEEP
o Gais et al. (2007)
 24 English-German vocabulary words
 IV: Sleep vs. Awake
 Sleep enhances consolidation
 Prevents retroactive interference
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o Wilhelm et al (2011)
 Trained on “concentration” type task
 IV: Expected later retest (yes/no)
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IMPROVING LEARNING AND MEMORY
o 1. Elaborate:
 Associate what you are learning to what you already know
o 2. Organize, generate, retrieve
o 3. Take breaks
 Memory is better for multiple short study sessions (reduce interference)
 Consolidation is enhanced if you sleep after studying (in other words, no
all nighters !)
o 4. Avoid “Illusion of learning”
 Familiarity ≠ comprehension
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SUMMARY
o Effectiveness of encoding
 Elaboration vs. maintenance
o Levels of processing
 Deep vs. shallow
o Consolidation
 LTP neural trace
o Next time: Everyday Memory & Memory Errors
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