Memory

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Memory
Rozalia Ivady
BME – Cognitive Science Department
ImpLab Scientific Society
Psychology Class, McDaniels College, 29th October 2007
Memory – an outline
 Multiple stores
 Retention curves – serial position data
 Memory dysfunctions
 Sensory memory
 Short term memory
 Long term memory
 Three processes
 Forgetting
 Explicit and implicit memory
 Constructive memory
 Psychology and the law
But before anything else
 Provo is a picturesque region of France.
 Corman was a pretender to the throne of
Provo.
 He was tired of waiting.
 He thought arsenic might work.
Try to remember these!
Look at these pictures
Now look carefully at these
pictures. You will need to
recall them later.
Memory – an outline
 Multiple stores





Retention curves – serial position data
Memory dysfunctions
Iconic memory
Short term memory
Long term memory
 Three processes
 Explicit and implicit memory
 Constructive memory
 Psychology and the law
Try to recall as many items as you can!
 Cat
 Chair
 Apple
 Screw
 Banana
 Pigeon
 Hammer
 Orange
 Toothpick
 Knife
 Parrot
 Bed
 Table
 Dog
 Blackberry
 Fork
 Fly
 Rat
Multiple stores or MLP?
Multiple stores or MLP?
Primacy effect
Recency effect
The Atkinson-Shiffrin Model
Maintenance Rehearsal
Sensory
Input
Sensory
Memory
Attention
Encoding
Working or
Long-term
Short-term
memory
Memory Retrieval
Memory dysfunctions - amnesia
Famous Anterograde Amnesiac: HM
 Severe epilepsy, treated with surgery to
bilaterally remove medial temporal lobes,
including hippocampus
 Operation 9/1953, 27 years old
Anterograde Amnesia
 Inability to acquire new information

“memento”

Does not affect short-term memory and general
knowledge from the past

But, it is difficult to learn new facts

Affects memory regardless of modality (visual,
auditory, tactile, etc). Spares skilled performance

Hyper-specific memory for those skills that are
learned after onset – learning is expressed only in
context in which it was encoded
Amnesia
 Types of amnesia
 Anterograde
 Retrograde
Memory – an outline
 Multiple stores





Retention curves – serial position data
Memory dysfunctions
Sensory memory
Short term memory
Long term memory
 Three processes
 Explicit and implicit memory
 Constructive memory
 Psychology and the law
There is more than we can tell…
 Eidetic pictures of
children
How many stripes did you
see on the cat?
Sensory Memory Store
 Function - holds information
Sensory
Input
Sensory
Memory
long enough to be
processed for basic
physical characteristics
 Capacity - large

can hold many items at
once
 Duration - very brief
retention of images


.3 sec for visual info
2 sec for auditory info
Sensory Memory Store
 Divided into two
subtypes:

Sensory
Input
Sensory
Memory

iconic memory - visual
information
echoic memory auditory information
 Visual or iconic memory
was discovered by
Sperling in 1960
Sperling’s Experiment
 Presented matrix of letters for
1/20 seconds
 Report as many letters as
possible
 Subjects recall only half of the
letters
 Was this because subjects
didn’t have enough time to
view entire matrix? No
 How did Sperling know this?
Sperling’s Experiment
 Sperling showed people can see
and recall ALL the letters
momentarily
 Sounded low, medium or high
tone immediately after matrix
disappeared

tone signaled 1 row to report

recall was almost perfect
 Memory for image fades after
1/3 seconds or so, making report
of entire display hard to do
High
Medium
Low
Sperling’s Iconic Memory
Experiment
Sperling’s Iconic Memory
Experiment
Sperling’s Iconic Memory
Experiment
Sperling’s Iconic Memory
Experiment
Sperling’s Iconic Memory
Experiment
G
A
V
M K
U
X
L
S
F
Q
J
O
N
U
A
N
Z
What Letters Do You See? DiLollo
…..
What Letters Do You See?
…..
…..
What Letters Do You See?
…..
Sensory Memory Store
 Sensory memory forms
Sensory
Input
Sensory
Memory
automatically, without
attention or
interpretation
 Attention is needed to
transfer information to
working memory
Memory – an outline
 Multiple stores





Retention curves – serial position data
Memory dysfunctions
Sensory memory
Short term memory
Long term memory
 Three processes
 Explicit and implicit memory
 Constructive memory
 Psychology and the law
Working Memory Store
Sensory
Input
Sensory
Memory
Attention
Working or
Short-term
Memory
The Atkinson-Shiffrin Model
Maintenance Rehearsal
Sensory
Input
Sensory
Memory
Attention
Encoding
Working or
Long-term
Short-term
memory
Memory Retrieval
Working Memory Store
 Function - conscious processing of information

where information is actively worked on
 Capacity - limited (holds 7 +/- 2 items)
 Duration - brief storage (about 30 seconds)
 Code - often based on sound or speech even
with visual inputs
Sensory
Input
Attention
Sensory
Memory
Working or
Short-term
Memory
Working Memory Store
 What happens if you need to keep
information in working memory longer than 30
seconds?
 To demonstrate, memorize the following
phone number (presented one digit at a
time)...
8 5 7 91 6 3
Working Memory Store
857-9163
 What is the number?
The number lasted in your working memory
longer than 30 seconds
So, how were you able to remember the
number?
Maintenance Rehearsal
 Mental or verbal repetition of information
Allows information to remain in working
memory longer than the usual 30 seconds
Maintenance rehearsal
Sensory
Input
Sensory
Memory
Attention
Working or
Short-term
Memory
Maintenance Rehearsal
 What happens if you can’t use maintenance
rehearsal?
 Memory decays quickly
 To demonstrate, again memorize a phone
number (presented one digit at a time)

BUT, have to count backwards from 1,000 by
sevens (i.e., 1014, 1007, 1000 … etc.)
6 2 8 50 9 4
Working Memory Store
628-5094
 What is the number?
Without rehearsal, memory fades
Peterson’s STM Task
 Test of memory for 3-
letter nonsense
syllables
 Participants count
backwards for a few
seconds, then recall
 Without rehearsal,
memory fades
Working Memory Model
 Baddeley (1992)
 3 interacting components
Visuospatial
Sketch Pad
Central
Executive
Phonological
Loop
Working Memory Model
 Visuospatial sketch pad - holds visual and spatial
info
 Phonological loop - holds verbal information
 Central executive - coordinates all activities of
working memory; brings new information into
working memory from sensory and long-term
memory
Visuospatial
Sketch pad
Central
Executive
Phonological
Loop
Long-Term Memory Store
 Once information passes from sensory to
working memory, it can be encoded into
long-term memory
Maintenance Rehearsal
Sensory
Input
Sensory
Memory
Attention
Encoding
Working or
Long-term
Short-term
memory
Memory Retrieval
Long-Term Memory Store
 Function - organizes and stores information

more passive form of storage than working
memory
 Unlimited capacity
 Duration - thought by some to be permanent
Maintenance Rehearsal
Sensory
Input
Attention
Sensory
Memory
Encoding
Working or
Long-term
Short-term
memory
Memory Retrieval
Review of Long-Term Memory
 Organizes and stores information
 Capacity unlimited
 Thought by some to be permanent
 Encoding transfers info from STM to LTM
Maintenance Rehearsal
Sensory
Input
Attention
Sensory
Memory
Encoding
Working or
Long-term
Short-term
memory
Memory Retrieval
Summary
 Modal model of memory

three memory stores (sensory, working and
long-term memory)
Three processes and sins of memory
 Encoding - process that controls
movement from working to long-term
memory store
 Storage
 Retrieval - process that controls flow of
information from long-term to working
memory store
Forgetting and the fight against it
 Elaboration
 Chunking
 Thories of forgetting



Problems in encoding
Problems of retention
Problems of retrieval – interference ,inhibition
Elaboration
 Focus on meaning of information to encode it
into LTM



don’t simply repeat items over and over
tie item to other info in memory
also called elaborative rehearsal
Ways to Use Elaboration
 Actively question new information
 Think about its implications
 Relate information to things you already know
 Generate own examples of concepts
 Don’t highlight passage as you read

focus on the ideas in the text
Which Level is More Effective?
 Elaboration leads to better recall than shallow
processing
Type of
Processing
Deep
0
Shallow -Acoustic
Shallow - Visual
10
20
30
40
50 60
70
80
Percent of words recalled
90 100
More Evidence for Elaboration
 Positive correlation between grades and use
of elaboration in 5th grade students
 In an experiment, college students assigned
to use elaboration received higher grades
than students not taught elaboration
Chunking
 Grouping small bits of information into larger
units of information

expands working memory load
 Which is easier to remember?


4 8 3 7 9 2 5 1 6
483 792 516
Visualization
 Key word method
 Method of loci
Forgetting Theories
 Encoding failure
 Role of time
 Interference theories
Forgetting as Encoding Failure
 Information never encoded into LTM
X
Encoding Failure Demonstrations
 What letters accompany the number 5 on
your telephone?
 Where is the number 0 on your calculator?
 According to this theory, objects seen
frequently, but information is never encoded
into LTM
Forgetting as Retrieval Failure
 Not all forgetting is due to encoding failures
 Sometimes information IS encoded into LTM, but we can’t
retrieve it
X
Role of Time : Decay Theory
 Memories fade away or
decay gradually if unused
 Time plays critical role
 Ability to retrieve info
declines with time after
original encoding
 Problem: Many things
change with time.
Something else may
change and actually
cause forgetting:
Interference
Interference Theories
 “Memories interfering with memories”
 Forgetting NOT caused by mere passage of time
 Caused by one memory competing with or replacing
another memory
 Two types of interference
Two Types of Interference
Types of interference
Retroactive
Interference
Proactive
Interference
Retroactive Interference
 When a NEW memory interferes with
remembering OLD information
 Example: When new phone number interferes
with ability to remember old phone number
Retroactive Interference
 Example: Learning a new language interferes with
ability to remember old language
Proactive Interference
 Opposite of retroactive
interference
 When an OLD memory
interferes with
remembering NEW
information
 Example: Memories of
where you parked your
car on campus the past
week interferes with
ability find car today
Proactive Interference
 Example: Previously learned language interferes with
ability to remember newly learned language
Retrieval Cue Theories
 Retrieval cue - a clue, prompt or hint that
can help memory retrieval
 Forgetting is the result of using improper
retrieval cues
Encoding Specificity Principle
 Learn word list
 generate ‘cue’ when
see word (jam - jelly)
 at recall cues given as
retrieval aid
(jelly or traffic)
 Cues generated during
learning (jelly) more
effective during retrieval
than new cues (traffic)
Context-Dependent Memory
 Improved ability to remember if tested in the same
environment as the initial learning environment


better recall if tested in classroom where you initially
learned info than if moved to a new classroom
if learning room smells of chocolate or mothballs,
people will recall more info if tested in room with the
same smell compared to different smell or no smell at
all
Context-Dependent Effects
 Compare words learned underwater vs on land
 Words heard underwater are best recalled
underwater
 Words heard on land are best recalled on land
Context Dependent Effects
 Time of day is also important
Learn at 3 pm
Perform better at 3 pm
Than 9 pm
12
12
12
9
3
6
9
3
6
9
3
6
State-Dependent Memory
 Recall improved if internal physiological or emotional
state is the same during testing and initial encoding
 Context vs State dependent
 Context-dependent - external, environmental factors

State-dependent - internal, physiological factors
State-Dependent Effects

Mood or emotions also a factor

Bipolar depressives
 information learned in manic state, recall more if
testing done during manic state

information learned in depressed state, recall
more if testing done during depressed state
State Dependent Effects
If drink during
learning
May recall better
with drink
Than without
But not as well
as sober all the
way!
Memory – an outline
 Multiple stores
 Retention curves – serial position data
 Memory dysfunctions
 Sensory memory
 Short term memory
 Long term memory
 Three processes
 Forgetting
 Explicit and implicit memory
 Constructive memory
 Psychology and the law
Constructing memories
 Recall the sentences from the beginning of
the lesson! Write them down.
Memory Construction
 Recall not an exact replica of original events
 Recall a construction built and rebuilt from various
sources
 Often fit memories into existing beliefs
 Remember those
drawings? Can you
draw them?
Time can be even shorter

The War of the Ghosts

One night two young men from Egulacwent 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 m 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 manywere 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.









 Recall the story
 3 months later
 Some warriors went to wage way against the ghosts. They
fought all day and one of their number was wounded.
 They returned home in the evening, bearing their sick comrade.
As the day drew to a close, he became rapidly worse and the
villagers came round him. At sunset he sighed: something black
came out of his mouth. He was dead.
Schema Theories
 Schema - mental representation of an object, scene
or event

example: schema of a countryside may include green
grass, hills, farms, a barn, cows, etc.
 Scripts - type of schema
 mental organization of events in time
 example of a classroom script: come into class, sit
down, talk to friends, bell rings, instructor begins to
speak, take notes, bell rings again, leave class, etc.
 Schemas & scripts provide framework for new
information
Eyewitness Testimony
 Memory can be distorted as people try to fit new info into
existing schemas
 Eyewitnesses usually see something complex just once
then have to remember it
 Sometimes new information is distorted by
 fitting into an existing schema
 subsequent information (famous experiment by Loftus)
Loftus Experiment
 Subjects shown video
of an accident between
two cars
 Some subjects asked:
How fast were the cars
going when they
smashed into each
other?
 Others asked: How fast
were the cars going
when they hit each
other?
Loftus’s Results
 Speed estimates
depended on how the
question was phrased
 Subjects memory for
broken glass also
depended on the
phrasing of the speed
question.

But this was a false
memory: there was no
broken glass
Memory – an outline
 Multiple stores
 Retention curves – serial position data
 Memory dysfunctions
 Sensory memory
 Short term memory
 Long term memory
 Three processes
 Forgetting
 Explicit and implicit memory
 Constructive memory
 Psychology and the law
Long-term Memory Systems
Long-term Memory
Explicit Memory
Episodic
Memory
Semantic
Memory
Implicit Memory
Procedural
Memory
Classical
Conditioning
Priming
Explicit Memory
 Also known as declarative or conscious memory
 Properties:
 memory consciously recalled or declared
 Can use to directly respond to a question
 Two subtypes of explicit memory
Subtypes of Explicit Memory
Explicit Memory
Episodic Memory Semantic Memory
Episodic Memory
 Memory tied to your own personal experiences
 Examples:
 what did you have for dinner?
 do you like to eat caramel apples?
 Why are these explicit memories?
 Because you can actively declare your answers to these
questions
Semantic Memory
 Memory not tied to personal events
 General facts and definitions about the world
 Examples:
 who was George Washington?
 what is a cloud?
 what is the climate at the north pole?
 These are explicit memories because you can describe
what you know about them.
 Unlike episodic memories, your knowledge does NOT
include your personal experience

i.e., You may never have been to the north pole but do know
about it.
Implicit Memory
 Also known as nondeclarative memory
 Influences your thoughts or behavior, but does not
enter consciousness
 Three subtypes
Subtypes of Implicit Memory
Implicit Memory
Classical
Conditioning
Procedural
Memory
Priming
Classical Conditioning
 Studied earlier
 Implicit because it
is automatically
retrieved
Procedural Memory
 Memory that enables you to perform specific
learned skills or habitual responses
 Examples:



Riding a bike
How to speak grammatically
Tying your shoe laces
 Why are these procedural memories implicit?
 Can’t readily describe their contents
 try describing how to tie your shoes
 They are automatically retrieved when appropriate
Priming
 Priming is influence of one memory on
another
 priming is implicit because it does not depend
on awareness and is automatic
 Here is a demonstration
Priming Demonstration
 Unscramble the
following words:
O R E S
 ROSE
L T E P A
 PETAL
K T A L S
 STALK
 TSME
 STEM
L O B S O M S
 BLOSSOM
 ELAF
Priming Demonstration
 ELAF = LEAF
 Why not respond
FLEA?
 Because flower parts
were primed
(flower power)
Priming
 Activation of one or more existing memories by a
stimulus
 Activation not a conscious decision
 BUT, can effect subsequent thoughts and actions
 Two types of priming
Two Types of Priming
Priming
Conceptual Perceptual
Conceptual Priming
 The semantic meaning of priming stimulus influences
your encoding or retrieval
 Thought to involve activation of concepts stored in
semantic memory
 Example: Flower power priming demonstration
 Does not depend on sense modality: pictures can
conceptually prime sounds AS THE NEXT SLIDE
SHOWS
Priming across modalities
 Look at the picture .
Then when the
instructor says a word,
write it down.
Perceptual Priming
 Prime enhances ability to identify a test stimulus
based on its physical features
 Does not work across sense modalities
Perceptual Priming
 Can you identify the
fragmented stimulus to
the right?
Perceptual Priming
 What if you were shown
the following slide earlier
in the lecture?
Perceptual Priming
 Can you identify the
fragmented stimulus to
the right?
Evidence for Separate
Implicit/Explicit Systems
 Neurophysiological evidence
 Patient H.M.
 life-threatening seizures originating in temporal lobe
 surgically removed portions of temporal lobe
Temporal Lobe
 Includes:
 hippocampus
 amygdala
Patient H.M.
 Surgery was effective in reducing seizures
 BUT, had other side effects as well
 Can remember explicit memories acquired before the
surgery

e.g., old addresses, normal vocabulary
 Cannot form NEW explicit memories
 e.g., remembering the name of someone he met 30
minutes prior
 cannot name new world leaders or performers
 can recognize a picture of himself from before his
surgery but not from after and doesn’t recognize
himself in a mirror
Patient H.M.
 H.M. has severe explicit / declarative memory
disorder
 H.M. is almost normal on procedural or implicit
memory tasks including priming, classical
conditioning, and learning motor skills
 This shows that explicit memory depends upon the
temporal lobes and implicit does not
Patient H.M. Summary
 Temporal lobe damage led to deficits in explicit, but
not implicit memory

H.M. had both episodic and semantic memory deficits
 Damage to the hippocampus alone produces
episodic, but not semantic memory deficits
 Why did H.M. show both types of explicit memory
deficits?

He had damage not only to hippocampus, but to other
structures as well
Memory – an outline
 Multiple stores
 Retention curves – serial position data
 Memory dysfunctions
 Sensory memory
 Short term memory
 Long term memory
 Three processes
 Forgetting
 Explicit and implicit memory
 Constructive memory
 Psychology and the law
Thank you for your attention, that
much on memory today….
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