LTM

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9am
Jimmy G. : has STM, has LTM only for longtime past, can’t form new LTM
LTM
LTM
Lenny in Memento: has STM, can’t form new LTM
LTM: what is it?
-not just storage
-LTM & Working Memory help create our present
-wealth of background information retrieval
Short-Term = Long-Term Memory?
Demonstration: Serial position curve.
Stimuli (Murdoch, 1962)
Barricade
Diet
Antenna
Meter
Journey
Crossbow
Muffler
Mouse
Menu
Children
Racket
Folio
Game
Phoenix
Doorbell
Sandwich
Colt
Airplane
Primacy effect:
-has time to rehearse and store in LTM
-first word attended 100% (no other presented before)
Recency effect:
-last words still in STM
Hypothesis 1: Primacy due to more rehearsal.
– Test: slower pace => more rehearsal possible.
– Result: Increased primacy effect
Glanzer and Cunitz (1966):
Hypothesis 2: Recency due to STM.
– Test: intermediate task (30 seconds counting backwards) prior to recall 
delete STM.
– Result: Reduced recency effect, can’t rehearse, 30sec enough to lose STM
Neurophysiological evidence for difference between STM and LTM:
Double Dissociation
suggests independent mechanisms
HM: hippocampus removed to avoid epileptic seizures
KF: digit span = 2; recency effect reduced
Semantic Coding of LTM (Sachs, 1967):
read passage and then multiple choice of what sentence was present in passage
The Galileo Story
There is an interesting story about the telescope. In Holland, a man
named Lippershey was an eyeglass maker. One day his children were
playing with some lenses. They discovered that things seemed very close
if two lenses were about a foot apart. Lippershey began experiments and
his "spyglass" attracted much attention. He sent a letter about it to
Galileo, the great Italian scientist. Galileo at once realized the
importance of the discovery, and set out to build an instrument of his own.
He used an old organ pipe with one lens curved out and the other curved
in. On the first clear night he pointed the glass towards the sky. He was
amazed to find the empty dark spaces filled with brightly gleaming stars!
Night after night Galileo climbed to a high tower, sweeping the sky
with his telescope. One night he saw Jupiter, and to his great surprise
discovered with it three bright stars, two to the east and one to the west.
On the next night, however, all were to the west. A few nights later there
were four little stars.
Which sentence did you read?
1. He sent a letter about it to Galileo, the great Italian scientist.
2. Galileo, the great Italian scientist, sent him a letter about it.
3. A letter about it was sent to Galileo, the great Italian scientist.
4. He sent Galileo, the great Italian scientist, a letter about it.
Changes:
1. None: identical.
2. Semantic: A difference in meaning.
3. Voice: Changed from active to passive
4. Formal: syntactic change, but same meaning.
Some participants remember the gist of meaning rather than exact sentence
-eyewitness testimony
10am
Declarative
-conscious recollection of events or facts
-episodic : personal events
-‘time travel’
-self-knowing (Tulving)
-semantic : facts and knowledge
-’no time travel’
-knowing (Tulving)
Double Dissociation
-demonstrates difference between episodic and semantic
-suggests independent mechanisms
KC (hippocampus injury) has memory “skeleton”, no details (richness lost)
Italian woman (encephalitis): trouble recognizing familiar people, meaning of
words on a shopping list; can tell lively stories about events
Are they different?
-brain imaging studies indicate overlapping
but different patterns of activation
-the jury is still out
Connections
-Episodic gateway to semantic: “morphing” episodic into semantic (only facts
remain about a personal event e.g. graduation)
-Episodic used to infer semantic information: better recall for names that I
have personal experience with (“I’m a fan of actor X”) Westmacott & Moscovitch (2003)
-Semantic knowledge can influence the formation of episodic memories
(e.g. remember more personal details about the game based on knowledge about
football)
Implicit
-not consciously aware when using it
-nonknowing (Tulving)
-repetition priming : response to item
increases in speed or accuracy
because has been encountered before
-procedural : how to do things
primed words completed more than new words
Repetition Priming (Tulving, 1962)
-words presented - priming stimulus
-fragment word to complete
Keyboard
Color
Truck
Table
Computer
c_lo_
Is repetition priming conscious?
Recognition & Recall
-recognition test: pick stimulus
previously presented
-delay of 1 hour or 7 days
Know it’s a
memory
task!
Is implicit memory conscious?
Warrington & Weiskrantz (1968):
Korsakoff’s syndrome patients
(lack of B1 vitamin, damage to
frontal and temporal lobe)
Procedural Memory
-no memory of where or when learned
-perform procedures without being
‘consciously’ aware of how we do them
Motor skills…
But also cognitive skills such as reading…
Implicit Learning
-mere exposure can affect behavior
Perfect & Askew (1994):
-higher ratings for ads previously
seen
-conscious recognition is not better
propaganda effect :
-rate statements previously seen or
heard as true even when told false at
the time
-eyewitness testimony...
11am
How is information stored in LTM?
CODING: form of stimulus for
memory (visual, auditory, semantic)
ENCODING: the process of storing
memories
How to encode?
encoding
LTM
retrieval
REHEARSAL
Maintenance
-repeat to keep in STM
-no transfer to LTM
-shallow memorization
-memory for phone #
Elaborative
-rehearse meaning
-transfer to LTM
-connect to existing knowledge
LEVELS-OF-PROCESSING THEORY (Craik & Lockhart, 1972)
-memory depends on HOW information is encoded
LIST#1: count vowels
LIST#2: how useful on deserted island
chair
mathematics
elephant
lamp
car
…
umbrella
exercise
forgiveness
rock
hamburger
…
Conclusion: memory depends on DEPTH OF PROCESSING
LEVELS-OF-PROCESSING THEORY
Craik & Tulving (1975) experiment:
TASK:
PROCESSING:
Does bird have capital letters?
SHALLOW
Does train rhyme with pain?
DEEPER
Does car fit? “He saw a ____ on the street.”
DEEPEST
TRANSFER-APPROPRIATE PROCESSING (Morris et al., 1977)
-circumstances of encoding and retrieval should match
DEPTH-OFPROCESSING
Did joy
rhyme
with a
word
from the
list?
?
What affects encoding:
DEPTH OF PROCESSING
TRANSFER-APPROPRIATE PROCESSING
...what else?
Forming connections with other information
Bower & Winzenz (1970)
using imagery to remember pairs of
words
Self Reference effect
-memory better if relate word to self
-self as a retrieval cue
-deeper processing
generation effect : generating material on your own
 enhances learning and retention
Slameka & Graf (1978):
28% more if generated
king-cr____ horse-sa____ lamp-sh___
Organization: Jenkins & Russell (1952)
spontaneously organize information
similar items group together
(and recalled together)
Bower et. al. (1969)
73:21 if organized in meaningful trees
[if all words are under right category]
Study guide… Organize your knowledge!
How is memory stored in the brain?
HEBB (1948): physiological changes at the synapse
LTP: long-term potentiation
Because these structural changes at the neural level take time to build up,
memory for distant past is more stable
memory for recent events more fragile than for remote events
H.M. had both types of amnesia
memory for recent events more fragile than for remote events
Why?
CONSOLIDATION
has to occur (which takes time)
Synaptic
(rapid)
Systems
gradual reorganization
of circuits
standard model of consolidation
during consolidation (recent memories) : retrieval depends on
hippocampus
after consolidation (remote memories): only cortical areas
hippocampus
Mechanism of consolidation: REACTIVATION (replay neural activity)
 Mostly true for semantic memories (hippocampus not active)
but... hippocampus also active during remote episodic memory retrieval as well
This result would call for the revision of the standard model of consolidation,
because standard model of consolidation claims that hippocampus active only in
the beginning.
Emotions
emotional and arousing words and pictures are
remembered better
emotion enhances process of consolidation
more activity in the amygdala
1pm
Retrieval
process of transferring information
from LTM into WM
most failures of memory are failures of
retrieval
encoding
retrieval
the memory is there, you just can’t
access it
Retrieval Cues
like ‘keys’ that help to retrieve the memory
associations between the cue and the memory help in
retrieving it
LTM
Cued Recall (Tulving & Pearlstone, 1966)
Recall the words
40%
Recall the words.
The categories
were birds,
furniture…
75%
Cued Recall (Mantyla, 1986)
create associations with 600 nouns: say 3 features about “banana”
peel, bunch, yellow
Encoding Specificity = transfer-appropriate processing
Context is also key!
Grant (1998)
State Dependent Learning
Internal state is also key!
Eich & Metcalfe (1989)
How to Study
elaborate and generate: elaborative rehearsal, not only
maintenance
“I read the book and notes twice.” ask questions
organize: outlines, ‘trees’, framework
associate: imagery, cues
take breaks: consolidation, sleep
match learning and testing conditions: encoding specificity,
state dependent learning
2pm
Memory occurs in real environments, not labs
Memory as a creative mental process
Errors
Fill in incomplete information
Everyday memory: “what I’m going to do later”
Remember what and when to do in future
Event-based tasks (cues can trigger memories)
better memories using distinctive versus familiar cues
Time-based tasks: take pill every morning
harder due to lack of cues
alarm clock converts it into event-based cue
Self (A)
Remembering Personal Experiences
Autobiographical memory = Episodic
Field perspective (what you saw)
vs
Observer perspective (what outsider observer saw)
Recent memories are experienced from a field
perspective
Distant memories are experienced from an
observer perspective (more abstract)
Cabeza et al. (2004):
Difference between personal and nonpersonal
Parietal cortex
Hippocampus
Other (L)
The Reminiscence Bump
Schrauf & Rubin (1998): Enhanced memory for (episodic and semantic)
facts of adolescence & young adulthood.
Two explanations:
1. Life-narrative hypothesis:
Personal identity is determined in those years.
2. Cognitive hypothesis:
Encoding is better in periods of rapid change,
followed by relative stability.
Question: How to argue for #2?
Find people who experienced rapid changes
at different life periods.
Hypothesis: Reminiscence bump should
shift…
Schrauf & Rubin (1998):
US immigrants
in 20s vs. 30s
=> shifted
(& attenuated)
reminiscence bump
Flashbulb Memories
What did you do on Sep 09 2001?
What did you do on Sep 11 2001?
What did you do on Dec 11 2001?
Phenomenon:
Shocking and emotionally charged events
tend to be remembered very vividly (and
more detailed than other events).
Question:
Do these phenomena highlight a special
memory mechanism?
FbM: A Special Mechanism
Brown & Kulik (1977):
FbM are created by a special ‘now print’ mechanism.
Conditions for invocation:
– emotionally charged circumstances
– high consequentiality of events
- no change or loss of details (like a photograph)
FbM: No Special Mechanism
Neisser (2000):
FbM reflect ordinary memory processes.
Conditions of invocation:
– Frequent narrative rehearsal:
saw it on TV million times
– Decay and inaccuracies:
FbM are often distorted, just like other
memories
FbM: Evidence against a Special Mechanism
Experimental method: Repeated recall (does memory change over time?)
Neisser & Harsch (1992): Challenger in 1986 vs. 1989
– Increased distortions were affected by common knowledge.
– Specifically: Increase in TV-memories from 21% to 45%.
Schmolck et al. (2000): O.J. Simpson in 1995 vs. 1998
– Increased inaccuracies => Decay mechanisms.
– “it seems unlikely that so-called flashbulb memories differ from ordinary
episodic memories in any fundamental way. (p. 44)
3pm
FbM: Evidence against a Special Mechanism
Experimental method: Repeated recall (does memory change over time?)
Neisser & Harsch (1992): Challenger in 1986 vs. 1989
– Increased distortions were affected by common knowledge.
– Specifically: Increase in TV-memories from 21% to 45%.
Schmolck et al. (2000): O.J. Simpson in
1995 vs. 1998
– Increased inaccuracies => Decay
mechanisms.
– “it seems unlikely that so-called
flashbulb memories differ from ordinary
episodic memories in any fundamental
way. (p. 44)
FbM: Evidence for & against?
• Talarico and Rubin (2003): 9/11 at 9/12 vs. 1/6/32 weeks later)
=> Illusion of better memory?
Davidson et al. (2006)
• Asked questions related to ...
• an event associated with 9/11
• an everyday event
• 1 year later, surprise retest
on events
• Cue provided for subject if
needed
• Congruence score (0-2)
Different results!?!
• Telarico: FbM and everyday memories decay at the same rate
• Davidson: Less decay for FbM
Why was recall for every day event
better in Telarico et al. ?
• Subs not surprised by retest
• Subs chose their own cues
Both support the idea that FbM declines
over time.
Why are we so confident in our inaccurate memories???
Memory is fallible
• But, we don’t realize just how fallible it
is...
• because memory is constructive, and is
based on...
• Familiarity
• Culture
• Knowledge
• Suggestion
When reporting what’s remembered:
omit
distort
change
fabricate facts and events
Proof that memory is constructive: Bartlett’s “War of the Ghosts”
English subjects read story, retell
• (is from Canadian folklore)
• Recall story
• Errors consistent with English culture
(“canoe”  “boat”; seal hunt  “sailing expedition”)
Proof that memory is constructive: remember high school grades
A’s accurately remembered 89% of the time
D’s accurately remembered 29% of the time
79/99 students inflated their grades
Why?
a) Better memory for better grades
b) “best guess” about most likely grade
How do we construct memories?
Source Misattribution (forget or mislabel source of memory)
• Jacoby et al. (1989): “Becoming Famous Overnight”
How do we construct memories?
Pragmatic inference:
If presence of object (hammer) is suggested/assumed by knowledge of the
context, it becomes part of memory (correctly or incorrectly).
4pm
Schema: knowledge about an event, experience
typical office has books
false memory reflects “office schema”
Script: knowledge about sequence of
actions
sets up expectations about what usually
happens
Brewer & Treyens (1981)
Solomon Shereshevskii: “the man who remembered everything”
too much memory is not good
need to forget
overload
We selectively remember IMPORTANT + FREQUENT things.
Misleading Postevent Information
How fast were the cars
going when they ____
each other?
“smashed into” : 41 mph
“hit” : 34 mph
Any broken glass?
“smashed into” : 32% said yes
“hit” : 14% said yes
Loftus & Palmer (1974)
Loftus & Palmer (1974)
Video about a car 
Group 1: “Did another car pass the first car at the stop sign?
Group 2: “Did another car pass the first car at the yield sign?
more likely to produce false memories
Lindsay (1990)
• Saw slide show narrated by a woman
• 2 days later, heard a story again (without slides)
• Changes:
cigarettes: MarlboroWinston
coffee: Maxwell HouseFolgers
• Same voice for both stories = source misattribution
Test:
what cigarettes?
what coffee?
what shoes? (control)
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