Memory
Zeus and Mnemosyne (Memory) were the parents of the
Muses, the guiding spirits of the Nine Arts.
Memory
• Defines who we are
• Informs what we will do
• Famous cases:
– Clive Wearing (http://www.youtube.com/watch?v=OmkiMlvLKto)
– S.V. Shereshevskii (A. Luria)
• The paradox of memory, it can last your lifetime or be
gone tomorrow, you can be unable to remember
something you want to recall, or incapable of ignoring
what you would like to forget.
Memory
• Types of Memory
– Iconic
• Masking
– Short-Term
• Mnemonics &
Working Memory
– Long term
• Implicit
• Explicit
– Levels of processing
• Processes
– Encoding, storage,
retrieval
– Forgetting
• Methods
– Recognition, recall
• Anatomy of
Memory
– Hippocampus and
Amygdala
Schacter’s “Seven Sins of
Memory”
•
•
•
•
•
•
•
Memories are transient (fade with time)
We do not remember what we do not pay attention to
Our memories can be temporarily blocked
We can misattribute the source of memory
We are suggestible in our memories
We can show memory distortion (bias)
We often fail to forget the things we would like not
to recall (persistence of memory)
A Tale of Three Memories
Memory
Iconic /
Sensory
Memory
Short Term /
Working Memory
Long-term
Memory
A Tale of Three Memories
• Iconic memory
– large capacity
– Same modality as experience
– Very fast decay
A Tale of Three Memories
• Short Term Memory,
– Limited capacity
– Acoustic recoding
– Rehearsal maintains information
• Probabilistic transfer into LTM
– information from LTM retrieved and used
here
A Tale of Three Memories
• Long term memory
– Unlimited capacity
– Semantic coding
– Little decay
Traditional Model of Memory
• Atkinson & Shiffrin (1968) 3 Stage Model
Stimuli
Sensory
registers
Short Term
Memory
(STM)
Information Processing Model
Long Term
Memory
(LTM)
Sensory Stores
• Iconic store or Visual sensory register
–
–
–
–
Holds visual information for 250 msec longer
Information held is pre-categorical
Capacity – up to 12 items
Information fades quickly
• Auditory sensory register
– Holds auditory information for a 2-3 seconds longer to
enable processing
Sperling (1960) Iconic Memory
Research
• Whole report procedure
– Flash a matrix of letters for 50 milliseconds
– Identify as many letters as possible
– Participants typically remembered 4 letters
• Partial Report Procedure
– Flash a matrix of letters for 50 milliseconds
– Participants are told to report bottom row
– Participants were able to report any row requested
Sperling Sensory Memory
Demonstration
• A matrix of 12 letters and numbers will be
briefly flashed on the next few slides
• As soon as you see the information, write
down everything you can remember in its
proper location
Whole Report
Here’s where the letters and numbers will appear-- Keep your eyes on the
“X” on the next slide
X X X X
X X X X
X X X X
B 5 Q T
2 HXS 9
O 4 M Y
B 5 Q T
2 H S 9
O 4 M Y
Partial Report – No Delay
For the next demonstration, report only the top, middle, or bottom row.
The row to report will be identified by markers IMMEDIATELY after
you see the letters.
X X X X
X X X X
X X X X
2 V 9 R
Q MX7 L
> K H 5 F <
2 V 9 R
Q M 7 L
> K H 5 F <
Averbach & Coriell (1961)
Iconic Memory Research
G E U L M F S X
WP M B D H J Y
- Showed matrix for 50 msec
-Place a small mark above a letter at different delays
- Backward visual masking: they found that if the marker was
near the target, you could remember it, but if it was in the same
location you would forget it. This is an example of spatial
interference.
Quizz
During his experiments studying iconic store, Sperling
would flash an array of stimuli (e.g., letters and/or
numbers) for approximately 50 milliseconds on a
screen. Asked to recall just the symbols presented on
the third line would be an example of the
a)
backward visual masking.
b)
forward visual masking.
c)
partial-report procedure.
d)
whole-report procedure.
Quizz
A second stimulus is presented shortly after the
first item in the same location and “erases” the
original stimulus. This is called
a) stimulus blocking.
b) synesthesia.
c) visuospatial sketchpad.
d) backward visual masking.
Short Term and Long Term Memory
• You experience memory as a single, unified
whole.
• Yet, remembering almost anything recruits
several systems and involves multiple
processes.
Memory Processes
• Encoding
– Processes used to store information in memory
• Sensory coding: Are things coded visually or
echoically? How would you test?
• Storage
– Processes used to maintain information in memory
• Rehearsal and elaboration
• Retrieval
– Processes used to get information back out of
memory
Two Kinds of Memory
• Evidence:
– The serial position curve.
– The task: I present you with a list and you recall it. You
can recall the words in any order and try to recall as many
as you can (called a free recall task).
– We graph the frequency of recall by serial position in the
list (first word, second word, etc.).
– Looking at that curve can tell us something about memory
stores.
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
ARTICHOKE
INSOMNIA
REST
TOSS
NIGHT
ALARM
NAP
SNOOZE
SNORE
NOD
PILLOW
TIRED
NIGHT
Did you recall?
Bed? Clock?
Snore? Pillow?
Night?
Artichoke?
Toss? Toss &
Turn?
Sleep?
Explanation
Primacy Effect
Recency Effect
Spacing Effect
Distinctiveness
Clustering
False Memory
Serial Position Curve
Serial Position Effect
Primacy effect – remembering stuff at
beginning of list better than middle because
of Rehearsal
Recency Effect – remembering stuff at the
end of list better than middle because of
lack of Interference
Serial Position Effect
Recall immediately
after learning
Recall several hours
after learning
LTM
Recall from
LTM
Recall from
Primacy effect – remembering stuff at
STM
beginning of list better than middle
Recency Effect – remembering stuff at
the end of list better than middle
Methods in Study of Memory
• Which type of memory test would you rather
have?
– An essay or a multiple choice exam?
– The difference between these two types of tests
captures the difference between a recall task
and a recognition
test
Recall Tasks
• Free Recall
– Recall all the words you can from a list you saw
previously
• Cued Recall
– Recall everything you can that is associated with Plato
in Psychology
– Participants are given a cue to facilitate recall
• Serial Recall
– Recall the names of all previous presidents in the order
they were elected
– Need to recall order as well as item names
Recognition Tasks
• Circle all the words you previously studied
• Indicate which pictures you saw yesterday
• The participant selects from a list of items
they have previously seen
Short-Term
Memory
Rehearsal
• Attention
– Attend to information in
the sensory store, it moves
to STM
Short Term
Memory
(STM)
• Rehearsal
– Repeat the information to
keep maintained in STM
• Retrieval
– Access memory in LTM
and place in STM
Attention
Storage &
Retrieval
Short Term Memory Demo
149162536496481
1 4 9 16 25 36 49 64 81
Memory Strategies: Organization
Works!
Research on Short-Term Memory
• Miller (1956)
– Examined memory capacity
– 7+/- 2 items or “chunks”
• Chunking -- organize the input into larger units
– 1 9 8 0 1 9 9 8 2 0 0 3 - Exceeds capacity
– 1980 1998 2003 - Reorganize by chunking.
Birthyear
H.S
graduation
College
Graduation
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
• Reaction time to respond
is measured
2
6,3,8,2,7
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
Memory Strategies: To get
from STM to LTM
• Mnemonic devices are strategies to
improve memory by organizing
information
– Method of Loci: ideas are
associated with a place or part of a
building
– Peg-Word system: peg words are
associated with ideas (e.g. “one is a
bun”)
– Interactive Images : verbal
associations are created for items to
Peg Word system Imagine the words interacting
Forgetting Is a Process,
Too!
Proactive interference:
old information interferes with recall of new
information
Retroactive interference:
new information interferes with recall of old
information
Decay theory:
memory trace fades with time
Motivated forgetting:
involves the loss of painful memories
(protective memory loss)
Retrieval failure:
the information is still within LTM, but
cannot be recalled because the retrieval cue
is absent
Issues in Memory
• Reasons for inaccuracy of
memory:
– Source amnesia: attribution of a
memory to the wrong source (e.g. a dream
is recalled as an actual event)
– Sleeper effect: a piece of information
from an unreliable source is initially
discounted, but is recalled after the source
has been forgotten
– Misinformation effect: we incorporate
outside information into our own
memories
Quizz
John is presented with the letter C followed by a square
less than 100 ms afterwards. He was not able to
report the letter.
a) The square interfered with getting the letter into
short term memory
b) The letter C was an iconic trace
c) The square was an instance of backward masking
d) All of the above
e) A and C only
Quizz
As a web designer, Samantha wanted to base her
site on mnemonic principles. Which of the
following techniques did she use:
a) Got as many links on one page as possible
b) Organized the links in groups of seven
c) Had very dynamic moving and flashing
banners
d) Organized the information into semantically
related groups
Baddeleys’ Working Memory Model
Central Executive
Visual Scribe
Visuo-spatial
Sketch Pad
Episodic Buffer
Articulatory Loop
Phonological
Store
Working Memory Model
• Articulatory Loop
– Used to maintain information for a short time and for
acoustic rehearsal
• Visuo-spatial Sketch Pad
– Used for maintaining and processing visuo-spatial
information
• Episodic Buffer
– Used for storage of a multimodal code, holding an integrated
episode between systems using different codes
Working Memory Model
• Central Executive
– Focuses attention on relevant items and inhibiting
irrelevant ones
– Plans sequence of tasks to accomplish goals, schedules
processes in complex tasks, often switches attention
between different parts
– Updates and checks content to determine next step in
sequence of parts
Demo Working Memory and
Phonological Loop
• Please memorize the following numbers
0 20 89 13 5 78 4 12 43 37 64 29
• Please answer the following questions
• A follows B
• B is not preceded by A
True/ False
True/False
• Please recall the list of numbers
0 20 89 13 5 78 4 12 43 37 64 29
Working Memory
• Context
– Trouble recognizing somebody at work when you
meet them on vacation
– Scuba divers learning a list of words under water
will recall it better underwater than on land
• State Dependent Recall
– Learning while happy or sad means better recall
while happy or sad (drunk too, but general
performance down)
End of Memory Part I
Long Term memory
Long-term Memory
Explicit Memory
Episodic
Memory
Semantic
Memory
Implicit Memory
Procedural
Memory
Classical
Conditioning
Priming
Examples of Types of Memories
• Episodic: “I bumped into a friend today at the
diner whom I hadn’t seen since last year.”
• Semantic: “George Washington was the first
President of the U.S.”
• Procedural Memory: Riding a bike
• Classical conditioning: Reflexes
• Priming: Jingles
Implicit and Explicit Memory
• Explicit memory tasks
– Recall in Voluntary and Conscious
– Also called Declarative memory
• Implicit memory tasks
– Involuntary and Unconscious
– Require participants to complete a task (the completion
of the task indirectly indicates memory)
– Also Called Non-declarative memory
Implicit / Explicit Memory
Priming Demo
• Hand out sheets to Group 1 and 2
Priming Demo
• Unscramble
•L T E P A
• PETAL
• PLATE
Priming
• Why did half the class say plate and the other
half say petal?
• They were primed to do so
• There were two different sheets of
unscrambled words
Priming sheet 1
• Unscramble the
following word:
• Answer:
•
•
•
•
•
•
•
•
•
•
•
•
FINEK
OPONS
KROF
PUC
ECUSAR
LT E PA
KNIFE
SPOON
FORK
CUP
SAUCER
P LAT E
Priming sheet 2
• Unscramble the
following word:
• Answer:
•
•
•
•
•
•
•
•
•
•
•
•
N Y PAS
F E LA
K TALS
DUB
LOBSOMS
LT E PA
PAN S Y
LEAF
S TALK
BUD
BLOSSOM
PE TAL
Levels of Processing
Craik & Lockhart
– Continuum of Processing
• Shallow: surface, perceptual features
• Deep: processed, meaningful interpretation
– Level or “depth” of processing affects its
memorability
– Deeper encoding produces more elaborate,
longer-lasting memory
Support for Levels of Processing
• Craik & Tulving (1975)
–
–
–
–
Participants studied a list in 3 different ways
Structural: Is the word in capital letters?
Phonemic: Does the word rhyme with dog?
Semantic: Does the word fit in this sentence? The ______
is delicious.
– A recognition test was given to see which type of
processing led to the best memory
Craik & Tulving (1975) Results
1
Case
0.9
Rhyme
Recognized
0.8
Sentence
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
Yes
No
Sentence Type
Other Forms of Deep Processing
• The importance of organization
– Taxonomic, hierarchical, thematic
•
•
•
•
Self-relevant information
Self-generation
Elaboration
Distinctiveness
Connectionist Perspective
• Parallel distributed processing model
– Memory uses a network
– Meaning comes from patterns of activation
across the entire network
– Spreading Activation Network Model
– Supported by priming effects
Memory for general knowledge
•Connectionist models
•Parallel processing
•Learning (unobserved)
•Layers (Input, Processing, Output)
•Nodes and Links
•Weights
•Increasingly popular, powerful
•Hard do damage, robust  plausible
James McClelland
Scripts and Schemas
• Notice the Verbal / Spatial connotations
Memory for general knowledge
• Scripts
– For routine events
– Restaurant example
– Allows inferences, problem of intrusions
Schemas
• We reconstruct memories according to a
“map” of behaviors that are highly related to
one another, and form a set.
–
–
–
–
Prior knowledge influences memory
Interpretation of details
Reductions in ambiguity
Makes unusual things stand out
Remember This
The procedure is actually quite simple. First, you arrange the items
into different groups. Of course one pile may be sufficient depending
on how much there is to do. If you have to go somewhere else due to
lack of facilities that is the next step; otherwise you are pretty well
set. It is important not to overdo things. That is, it is better to do too
few things at once than too many. In the short run this may not seem
important but complications can easily arise. A mistake can be
expensive as well. At first, the whole procedure will seem
complicated. Soon, however, it will become just another facet of life.
It is difficult to foresee any end to the necessity for this task in the
immediate future, but then, one can never tell. After the procedure is
completed one arranges the materials into different groups again.
Then they can be put into their appropriate places. Eventually they
will be used once more and the whole cycle will then have to be
repeated. However, that is part of life.
Recall The Last Slide
I have one word for you:
LAUNDRY
Try recalling the list again
• Schemas in action
(There is no meaningful difference
between chunks and schemas)
Quizz
Frankie plays the stock market, remembering the tickers (the
initials of the company name used in the stock market, like
GOG for Google) of corporations using various strategies.
a) She associates the tickers with a series of pre-set words. This
is the Method of Loci
b) She has created a fantasy story using the tickers as names of
heroes, and the companies as names of castles. This relates
to LOP and self-generation.
c) She picked companies where she has worked in the past.
This relates to working memory.
d) She imagines a taking a walk through her house, seeing the
tickers and the names of the companies in photographs or
labels. This is related to LOP for self-reference.
If You Do Not Retrieve from
LTM…
• Has the memory disappeared?
or
• Is the memory still there but cannot retrieve it
(available, but not accessible)?
Evidence Supporting “Still There”
Theory
Nelson (1971)
Paired associate List
43-house
67-dog
38-dress
77-scissors
Cued recall test
43- ________
67- ________
Two week delay
Subjects recalled 75% of items
on list
But focus was on 25% they
forgot.
Nelson (1971) Critical Manipulation
If participants forgot “38-dress” and “77-scissors” then participants
relearned either same pairs or changed pairs
25% “forgot” Relearned
Results
Same
38-dress
77-scissors
38-dress
77-scissors
78%
Changed
38-dress
77-scissors
38-apple 77kettle
43%
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.
The Reconstructive Nature of Memory
The War of the Ghosts
One night two young men from Egulac went down to the river to hunt seals, and
while they were there it became foggy and calm. Then they heard war-cries,
and they thought: "Maybe this is a war-party". They escaped to the shore,
and hid behind a log. Now canoes came up, and they heard the noise of
paddles, and saw one canoe coming up to them. There were five men in the
canoe, and they said: "What do you think? We wish to take you along. We
are going up the river to make war on the people".
One of the young men said: "I have no arrows". "Arrows are in the canoe", they
said. "I will not go along. I might be killed. My relatives do not know where I
have gone. But you", he said, turning to the other, "may go with them.”
So one of the young men went, but the other returned home. And the warriors
went on up the river to a town on the other side of Kalama. The people came
down to the water, and they began to fight, and many were killed. But
presently the young man heard one of the warriors say: "Quick, let us go
home: that Indian has been hit". Now he thought: "Oh, they are ghosts". He
did not feel sick, but they said he had been shot. So the canoes went back to
Egulac, and the young man went ashore to his house, and made a fire. And he
told everybody and said: " Behold I accompanied the ghosts, and we went to
fight. Many of our fellows were killed, and many of those who attacked us were
killed. They said I was hit, and I did not feel sick". He told it all, and then he
became quiet. When the sun rose he fell down. Something black came out of
his mouth. His face became contorted. The people jumped up and cried.
He was dead.
Bartlett’s Ghost Story
• Changes occurred by
– Omission. Ghosts omitted early, wounds of the
spirit become wounds of the flesh
– Rationalization. Growing more coherent
– “Conventionalization”
– Temporal order. Change in order of events
“No trace of an odd or supernatural element is
left: we have a perfectly straightforward story
of a fight and a death”
The Reconstructive Nature of Memory
• Bartlett
– Assigning a name influences the reproduction.
– The transformations are in the direction of conventional
representations (highest frequency of exposure)
– Features that are not at first recognized are elaborated until
recognition is produced
– Once a recognizable feature is produced, it is reduced to its
most conventional simplification
The Reconstructive Nature of Memory
•
Loftus
The Reconstructive Nature of Memory
•
Loftus
• Replicated on a group of people
– What memories did people remember?
• 7 out of 24 remembered the false event
– How are the events remembered?
• True memories described more
• True memories rated more clear
• False memories’ clarity increased over time
– Can they choose the false memory?
• 19 out of 24 figured out which was false
• Process of elimination?
One Person’s False Memory...
• “I vaguely, vague, I mean this is very vague, remember the lady
helping me and Tim and my mom doing something else, but I don't
remember crying. I mean I can remember a hundred times crying..... I
just remember bits and pieces of it. I remember being with the lady. I
remember going shopping. I don't think I, I don't remember the
sunglasses part.“
• "Well, it can't be Slasher, 'cause I know that he ran up in the...the
chimney and I know that that cat got smashed and I know that we got
robbed so it had to be that mall one.”
• "..I totally remember walking around in those dressing rooms and my
mom not being in the section she said she'd be in. You know what I
mean?"
Individual Differences
• Some people are more susceptible to
misinformation than others
– 7 out of 24 participants
• People high at risk for misinformation
acceptance have
– Poor general memory
– High scores on imagery vividness
– High empathy scores
The Neuro-anatomy of Memory
• Hippocampus
• Amygdala
Hippocampus
Anatomy of
Memory
Amygdala: emotional memory and memory consolidation
Basal ganglia & cerebellum: memory for skills, habits and
CC responses
Hippocampus: memory recognition, spatial, episodic
memory, laying down new declarative long-term memories
Thalamus, formation of new memories and working
memories
Cortical Areas: encoding of factual memories, storage of
episodic and semantic memories, skill learning, priming.
H.M.
Or
Got Memory?
-Prior to 1953, the role of the MTL in memory was
relatively unknown
-H.M. changed all that: bilateral temporal lobectomy =
complete anterograde amnesia
-Brenda Milner’s neuropsychological testing
H.M.’s retrograde amnesia
70
60
50
40
-Famous Faces
performance is normal
for 40s, then below
normal for 50s, then
severely impaired in the
60s & 70s
30
Comparison
% Correct
-H.M.s RA extends
back ~11 years presurgery
20
H.M.
10
0
1940s
1950s
1960s
1970s
Famous Faces Recognition by Decade
Intact domains of memory in amnesia
-Working memory:
HM’s digit span is
normal
-Skill and Perceptual
learning
Perceptual Learning
Gollins partial pictures
test
What does the Hippocampus Do?
• Place cells neurons that respond when you are in a
specific place, in the place field of the neuron. So a
place cell would fire when you are in your bedroom
or house, etc. Each hippocampal neuron has a place
field in many different environments. At first when
you put the rat in the new environment, no neurons
fire. Then as the rat becomes familiar with the room,
neurons fire for particular parts of the room.
What does the Hippocampus Do?
• Configural Association Theory The theory
that the hippocampus retains the interrelation
among cues, spatially and temporally. So it
remembers the relationship between a visual
cue and a location as signaling food.
• Path Integration Theory the hippocampus
calculates current location, past location, and
future location from one’s own movement.
The Amygdal: Fear
and Memory
Amygdala
• • The amygdala modulates the formation of memories
in other brain structures, such as the hippocampus.
Information or events of particular emotional /
motivational significance are better remembered than
those of little importance (c.f. flashbulb memory).
• Lesions in humans and primates reveal a role for the
amygdala in the perception of emotional cues and the
generation of emotional responses, particularly those
associated with negative emotions such as fear.
Amygdala
• • Amygdala lesions before retention testing
disrupt conditioned fear. Hence, the amygdala
may be the site of storage of fear memories.
• Temporary inactivation by drugs during
acquisition has the same effect, suggesting a
genuine role in memory encoding.
The End of Memory
Forensics and Memory: False Confessions
Forensics and Memory: False Confessions
Forensics and Memory: Brief Overview of
Criminal Justice System
•
•
•
•
74% of crimes do not result in arrest
76% of charges are dropped or juvenile
22% of charges go to trial
Only about 14 of 1000 crimes committed will
actually go to trial – criminal or civil
Concepts to know
•Interference:
Proactive
1
vs.
2
Retroactive
1
•Explicitness:
Explicit
vs.
Bla
Implicit
2
Concepts to know
•Modal model of memory:
Sensory memory  Short term memory
Storage
Long term memory
Retrieval
Information
Response
•Encoding specificity
-Context effect
-State dependent
learning
Concepts to know
•Working memory = structured STM
Central
executive
Visuospatial
sketchpad
Phonological
loop
•Memory structure
LTM
Knowing how to...
Knowing that...
Declarative
Procedural
Implicit
Episodic
Vivid Recall
Semantic
Knowing
Explicit
Nickerson & Adams
Nickerson & Adams
1c