Download Memory

Memory
Human Memory
• The cognitive perspective understands
memory as
– A system that includes all of the information in a
person’s mind and,
– The mind’s capacity to store and retrieve that
information`
Three Stage Memory Processing
• Encoding : putting info into our brains
• Storage: keeping the info you put into your
brains
• Retrieval: getting the info from your brain
back out to use
• Encoding
– The processing of information into our memory
system
– Many ways in which we encode, or acquire,
information
• Visual Encoding
– Encoding of picture images
• Acoustic Encoding
– Encoding of sound, especially the sound of words
ENCODING
• Automatic Processing
– Unconscious encoding of incidental information
• Space
• Time
• Frequency
– Effortless processing
– All of this processing occurs without needing to
pay attention because of the brain’s ability to
parallel process
• Effortful Processing
– Encoding that requires attention and conscious
effort
• Experience and practice make these processes
automatic
– Ex. Reading, walking
• Often produces durable and accessible memories
– Rehearsal
• Conscious repetition of information, either to maintain
it in consciousness or to encode it for storage
• Rehearsal cont…
– We retain information better when rehearsal is
distributed over time
– Known as the Spacing Effect
• Thus, it is always better to study information over time,
instead of just cramming
– Serial-Position Effect (Combination of Primacy and
Recency Effects)
• Our tendency to best recall the first and last items in a list
• BUT, after a delay, recall is best of the first items
• Encoding cont…
– Semantic encoding
• Encoding of meaning, including the meaning of words
• Processing by meaning produces better recognition at
a later time, than does shallow processing
(visual/acoustic)
• Imagery (mental images) combined with semantic
encoding is a powerful way to remember
– Our most vivid images tend to color our memories
– Highly durable, but they can be of our best and worst
moments
• Semantic encoding cont…
– Mnemonics
• Memory aids, especially techniques that use vivid imagery
and organizational devices
– Examples include acronyms
» HOMES, ROY G BIV, SWAT, SEAL
– My Very Eager Mom Just Served Us Nine Pizzas (9 Planets)
– Chunking
• Organizing items into familiar, manageable units; often
occurs automatically
• Happens so naturally that we take it for granted
• We remember best when we can organize information into
personally meaningful arrangements
Remember this…
9.29181218121776235459045007
How to remember that number
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9.29 = today’s date
1812 = War of 1812
1812 = Repeats
1776 = Declaration of Independence
235 = 2+3=5
459045 = 45 x 2 = 90/2 = 45 (Or think of a
triangle)
• 007 = James Bond
Fun with Memory
• You have 30 seconds to look at the following
letters:
• CI AFB IKG BDN ABB C UKC NNU SA
Fun with Memory
• You have 10 seconds to look at the following
group of letters:
• CIA FBI KGB DNA BBC UK CNN USA
Dog
Cat
Horse
Cow
Apple
Orange
Pear
Banana
Chair
Table
Bed
Sofa
Knife
Gun
Rifle
Bomb
Cotton
Wool
Silk
Rayon
Blue
Red
Green
Yellow
Knife
Spoon
Fork
Pan
Hammer
Saw
Nails
Screwdriver
Oil
Gas
Coal
Wood
Doctor
Lawyer
Teacher
Dentist
Football
Baseball
Basketball
Tennis
Shirt
Socks
Pants
Shoes
ANIMALS
Dog
Cat
Horse
Cow
FRUIT
Apple
Orange
Pear
Banana
FURNITURE
Chair
Table
Bed
Sofa
WEAPONS
Knife
Gun
Rifle
Bomb
CLOTH
Cotton
Wool
Silk
Rayon
COLORS
Blue
Red
Green
Yellow
UTENSILS
Knife
Spoon
Fork
Pan
TOOLS
Hammer
Saw
Nails
Screwdriver
FUELS
Oil
Gas
Coal
Wood
PROFESSIONS
Doctor
Lawyer
Teacher
Dentist
SPORTS
Football
Baseball
Basketball
Tennis
CLOTHING
Shirt
Socks
Pants
Shoes
Types of Memory
• Short-Term Memory
– Activated memory that holds a few items briefly
before the information is stored or forgotten
– Involves conscious, active processing of incoming
auditory and visual-spatial information, and of
information retrieved from long-term memory
• Has a limit of 5-9 items (and retention time of about 30
secs)
– 7 digits of a phone number while dialing
– Also known as the “Working” memory
Types of Memory
Long-Term Memory
– Relatively permanent and limitless storehouse of the
memory system
• Includes knowledge, skills, and experiences
• Implicit Memory (Type of long-term)
• Procedural Memory
• Our motor and cognitive skills
– Walking, talking, reading, writing, driving, riding a bike, etc.
– Retention is independent of conscious recollection
– Effects of classic and operant conditioning are found
in this sub-type of long-term memory
• Explicit Memory
– Memory of facts and experiences that one can
consciously know and “declare”
• Declarative memory
• Semantic and episodic memories are found within this
sub-type
Storage
Definition:
• Retaining Information
• Keeping information in our brains
• Working Memory/Short Term Memory
• Long Term Memory
Storage
– Sensory Memory
• The immediate, very brief recording of sensory
information
• Iconic Memory
– Momentary sensory memory of visual stimuli
– Photographic or picture-image memory last no more than a
few tenths of a second
» We have amazing visual recall ability but only for a split
second
– Our visual screen clears quickly
Storage
• Sensory memory cont…
– Echoic memory
• Momentary sensory memory of auditory stimuli
• If attention is elsewhere, sounds and words can still be
recalled within 3 or 4 seconds
– How we are able to remember the last words in a
conversation where we were not paying full attention
Stress and Memory
• During periods of stress, our bodies react
making more glucose available to fuel the
brain, the limbic system is activated and
proteins are released in the memory-forming
areas of the brain.
• Arousal can both sear certain events into our
brains and disrupt memory of events
happening at the same time.
Memory
• Flashbulb Memory
– A clear memory of an emotionally significant
moment or event
• JFK’s assassination, 9/11, etc. are common examples
for recent generations of Americans
Retrieval
Definition:
• Getting the information out
Fun with Memory
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Name the Capitals of the following countries:
Norway
France
Tibet
Italy
Uruguay
Australia
Spain
Poland
Denmark
Peru
Egypt
Nicaragua
Thailand
Retrieval Cues
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What if I gave you hints?
Norway
O
France
P
Tibet
L
Italy
R
Uruguay
M
Australia
C
Spain
M
Poland
W
Denmark
C
Peru
L
Egypt
C
Nicaragua
M
Thailand
B
Retrieval Cues
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What if I gave you hints?
Norway
Os
France
Pa
Tibet
L
Italy
Ro
Uruguay
Mo
Australia
Ca
Spain
Ma
Poland
Wa
Denmark
Co
Peru
Li
Egypt
Ca
Nicaragua
M
Thailand
Ba
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Answers
Norway
France
Tibet
Italy
Uruguay
Australia
Spain
Poland
Denmark
Peru
Egypt
Nicaragua
Thailand
Oslo
Paris
Lhasa
Rome
Montevideo
Canberra
Madrid
Warsaw
Copenhagen
Lima
Cairo
Managua
Bangkok
Retrieval
• State-Dependent Memory (a.k.a. Mood
Congruent Memory)
– What we learn in one state is sometimes more
easily recalled when we are again in that state
• Joyful, sad, drunk, or sober
• Depression and being drunk disrupts encoding and
storage, therefore sometimes memories are more
easily recalled when in that state again
Examples of
State Dependent Memory
• Rats taught to run a maze under the influence of a depressant drug
will often forget the route through the maze if tested later without
the drug. Given the drug again, they retrieve their memory and run
the maze successful.
• Heavy drinkers may forget what they did while drunk, only to
remember again the next time they drink. This phenomenon
has been documented under experimental conditions using
word lists.
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Blount and Cox (1982) tested 80 college students at the University of Minnesota in
Morris, looking for evidence of state-dependent learning effects due to caffeine.
Subjects who consumed caffeinated drinks during the learning phase were
compared with subjects who did not. Half of each group was given caffeinated
drinks before the memory test. There was no effect due to the caffeine. The
researchers concluded, "Caffeine's effects on memory are different from the
effects of depressants.”
Retrieval
• Context-Dependent
• The tendency to recall experiences that are
consistent with one’s current good or bad
mood
• When we are sad, we tend to think about other sad
moments/experiences
• when a student tries to recall information in
an exam, they will be able to recall it best if
they learned it in an environment which is
similar to the exam environment
Forgetting
• Seven Sins of Memory
• Three Sins of Forgetting:
– Absent-Mindedness: Inattention to details
produces encoding failure (Mind elsewhere as you
put down car keys)
– Transience: Storage decay over time (unused
information fades)
– Blocking: Inaccessibility of stored information
(retrieval failure)
Forgetting
• Three Sins of Distortion:
– Misattribution: Confusing the source of
information (putting words in someone else’s
mouth)
– Suggestibility: lingering effects of misinformation
(a leading question later becomes a false memory)
– Bias: belief-colored recollections (current feelings
towards someone may color their initial feelings)
Forgetting
• One Sin of Intrusion:
– Persistence: Unwanted memories (being haunted
by images of a violent attack)
Sins of Forgetting
• Encoding Failure
• We cannot remember what we have not
encoded
• Information is not encoded from short-term to
long-term memory, therefore it cannot be
remembered
Encoding Failure
• http://www.exploratorium.edu/exhibits/com
mon_cents/index.html
Sins of Forgetting
• Storage Decay
– Even if we encode something well, we can forget it
later on
• Ebbinghaus’ Forgetting Curve
– Much of what is learned is quickly forgot
– BUT, levels off over time
– Ebbinghaus and Bahrick’s experiments
– Still learning about why the physical storage of
memory decays
Ebbinghaus’ Curve
U.S. Capitals
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South Dakota
Montana
Iowa
Florida
Mississippi
Texas
Vermont
Maine
Rhode Island
Nevada
Colorado
California
New York
Illinois
Capitals
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South Dakota
Montana
Iowa
Florida
Mississippi
Texas
Vermont
Maine
Rhode Island
Nevada
Colorado
California
New York
Illinois
P
H
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J
A
M
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P
C
D
S
A
S
Capitals
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South Dakota
Montana
Iowa
Florida
Mississippi
Texas
Vermont
Maine
Rhode Island
Nevada
Colorado
California
New York
Illinois
Pi
He
Io
Ta
Ja
Au
Mo
Au
Pr
Ca
De
Sa
Al
Sp
Capitals
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South Dakota
Montana
Iowa
Florida
Mississippi
Texas
Vermont
Maine
Rhode Island
Nevada
Colorado
California
New York
Illinois
Pierre
Helena
Iowa City
Tallahassee
Jackson
Austin
Montpelier
Augusta
Providence
Carson City
Denver
Sacramento
Albany
Springfield
Sins of Forgetting
• Retrieval Failure
• Sometimes information gets into our brain
that we just cannot get out
• “Tip-of-the-Tongue” phenomenon
• Information is there wanting to be retrieved
• Takes a retrieval cue for the person to be able to
retrieve the information
Tip-of-the-Tongue
• Tip-of-the-tongue (TOT)
– Sometimes we know we know something
– We cannot quite access the information
• Often it is a word that will not come to mind
• Characteristics of Tip of the tongue states
– Can often guess the first letter
– Can often tell the shape of the word (such as the
number of syllables
– TOT states can be frustrating
Sins of Forgetting
• Interference
– Proactive Interference: the disruptive effect of
prior learning on the recall of new information
– Retroactive Interference: the disruptive effect of
new learning on the recall of old information
• You can minimize the effects of Retroactive
Interference by reducing the number of interfering
events
– Go for a walk or go to sleep (an hour) after learning new
information increases retention
The Interferences
Forgetting
• Positive Transfer: When old information is able
to facilitate learning of new information
– Interference occurs when old and new
information compete with each other
Amnesia
• Source Amnesia: Attributing to the wrong
source an event that we have experienced,
heard about, read about, or imagined.
– At the heart of many false memories
Amnesia
• Anterograde Amnesia: Form of amnesia where
new events are not transferred to long-term
memory.
– Those who suffer from theoretically pure anterograde
amnesia will still be able to remember memories laid
down before the onset of anterograde amnesia
• But will exist in a transient world where anything beyond
their immediate attention-span disappears permanently
from their consciousness.
– Different types of memories (e.g., of new physical
skills, of new words, of the events of the day, facts of
history, etc.) can be separately affected by
anterograde amnesia.
Amnesia
• Anterograde amnesia cont…
– Patients with anterograde memory loss often can
learn and remember a new physical skill and yet
not remember when he or she had learned it.
– Examples have been described where patients
learned and remembered new words and facts of
history ("semantic" memory) but could not
remember any events of their previous day
("episodic" memory).
Amnesia
• Large intake of alcohol can cause anterograde
amnesia
– Commonly referred to as blackouts.
• Damage to the hippocampus
– Famous Cases:
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Clive Wearing
50 First Dates
Memento
Dory, the blue fish, from Finding Nemo
Amnesia
• Retrograde Amnesia: A form of amnesia
where someone will be unable to recall events
that occurred before the onset of amnesia.
– Retrograde amnesia is caused by trauma that
results in brain injury.
– Retrograde amnesia is often temporally graded,
meaning that remote memories are more easily
accessible than events occurring just prior to the
trauma.
Amnesia
• The memory loss may just affect specific
“classes” of memory.
– For instance the victim, a concert pianist before, may
still remember what a piano is after the onset of
retrograde amnesia, but may forget how to play.
– The relearning rate for often used skills such as typing
and math is typically faster than if they had never
learned it before.
– The victim of retrograde amnesia may feel
embarrassed or stressed that they no longer
remember key people and significant events
Forgetting
Sins of Distortion
• Misattribution: Source Amnesia
• Suggestibility: Incorporating misleading
information into one’s memory of an event.
• Misinformation Effect
– As a memory fades with time following an event, the
injection of misinformation becomes easier
– Brings doubt into eyewitness accounts
– Even repeatedly imagining nonexistent actions and
events can create false memories
Reconstructive Memory
Reconstructive Memory
• Reconstructive Memory:
– Recall that is hypothesized to work by storing
abstract features which are then used to construct
the memory during recall
• Loftus experiment
– We “fill-in-the-gaps” when recalling previous
memories
– Often leads to false memories that we are very
confident in
Flashbulb Memory
• Underline the facts – just
the facts
• Highlight the emotions
• Circle the auditory stimuli
• Box the visual stimuli
Loftus Experiment
1974
• The aim of this study was to investigate how
information supplied after an event,
influences a witness's memory for that event.
• demonstrated through the use of leading
questions how it is possible to distort a
person’s memory of an event
1st Experiment
• 45 students of Univ. of Washington
• Shown seven film-clips of traffic accidents
(driver ed films 5-30 seconds long)
• Asked to write an account of accident and
answer specific questions
• Independent variable was manipulated by
means of wording of the questions
1st experiment
• For example:
• Condition 1: 'About how fast were the cars going
when they smashed into each other?'
• Condition 2: 'About how fast were the cars going
when they collided into each other?'
• Condition 3: 'About how fast were the cars going
when they bumped into each other?'
• Condition 4: 'About how fast were the cars going
when they hit each other?
• Condition 5: 'About how fast were the cars going
when they contacted each other?'
1st experiment results
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Loftus and Palmer give two interpretations/explanations of the findings of their 1st experiment.
1.
Firstly, they argue that the results could be due to a distortion in the memory of the participant.
The memory of how fast the cars were travelling could have been distorted by the verbal label which had
been used to characterize the intensity of the crash.
2.
Secondly, they argue that the results could be due to response-bias factors, in which case the
participant is not sure of the exact speed and therefore adjusts his or her estimate to fit in with the
expectations of the questioner. (This is also an example of a demand characteristic)
Verb
Mean Estimate of Speed
Smashed
40.8
Collided
39.3
Bumped
38.1
Hit
34.0
Contacted
31.8
2nd experiment
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150 student participants viewed a short (one minute) film which contained a 4
second scene of a multiple car accident, and were then questioned about it.
There were three conditions and the independent variable was manipulated by
the wording of the question.
50 of the participants were asked 'How fast were the cars going when they hit
each other?’
50 of the participants were asked 'How fast were the cars going when they
smashed into each other?'
50 of the participants were not interrogated about the speed of the vehicles.
One week later, the participants returned and, without viewing the film again, they
answered a series of questions about the accident. The critical question was 'Did
you see any broken glass?' The critical question was part of a longer series of
questions and was placed in a random position on each participants question
paper. There was in fact no broken glass in the film.
2nd experiment Results
Response
Smashed
Hit
Control
Yes
16
7
6
No
34
43
44
Loftus argued that two kinds of information go into a person's memory of an
event. The first is the information obtained from perceiving an event (e.g.
witnessing a video of a car accident), and the second is the other information
supplied to us after the event (e.g. the question containing hit or smashed).
Over time, the information from these two sources may be integrated in such a
way that we are unable to tell from which source some specific detail is
recalled. All we have is one 'memory'. This explanation is often referred to as
the reconstructive hypothesis.
Reconstructive Memory
• Tom was flying from San Diego to the Bahamas
on Flight #639. After the flight took off, three
men from the People’s Liberation for Oppressed
Peoples hijacked the flight and wanted to divert
the plane to Panama. The Pilot Jane and Co-Pilot
Jack locked the cockpit door and attempted to
land the plane in Texas. The hijackers tried to
break down the cockpit door, but were
unsuccessful. Jane took the gun from the cockpit
and shot two of the hijackers. Passengers
subdued the other hijacker, as Jane was able to
land in New Orleans.
Reconstructive Memory
• Reconstructive Memory
• Leveling‐ simplifying the story
• Sharpening‐ overemphasizing or highlighting
certain details
• Assimilating‐ changing details to fit own
background or knowledge
Eye-Witness Testimony
• http://www.psychology.iastate.edu/faculty/g
wells/homepage.htm
Forgetting
Facial Recognition
• How do we remember a face?
– The upper part of the face seems to be more
important for recognition than the lower part.
– The hair turns out to be the most important
factor, followed by the eyes, then the nose, and
then to a lesser extent, the mouth and chin.
• So if you're going to rob a bank, wear a wig,
and don't bother with the fake beard.
Fun with Memory
• http://www.youramazingbrain.org/testyoursel
f/eyewitness.htm
• http://www.lumosity.com/
• http://www.lumosity.com/braingames/problem-solving-games/word-sort