Transcript memories

Memory:
Retrieving &
Forgetting
1
Measures of Memory
In recognition the person has to identify an item
amongst others e.g., a multiple-choice test
requires recognition.
1. Which is the capital of Kyirblahkyrstan?
a.
b.
c.
d.
Trilv
Groist
Vlikt
Zostra
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Measures of Memory
In recognition the person has to identify an item
amongst others e.g., a multiple-choice test
requires recognition.
1. Which is the capital of Kherblahkyrstan?
NONE ARE CORRECT!
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Measures of Memory
In recall the person must retrieve information
using effort, e.g., fill-in-the blank tests require
recall.
1. The capital of Palau is ______.
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Palau
Melekeok
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http://www.innocenceproject.org/
“When I first saw the photo of him and I saw the
pictures of the men that were in front of me.
Ronald Cotton--he just looked exactly like the
man who raped me. And not a lot of time had
elapsed between the crime and me looking at the
pictures, so my memory was still very fresh. And
then when I saw him in the physical line up and I
was actually able to see him as a person and
his demeanor and his postures--it just further
convinced me that Ronald Cotton was the man.
He looked exactly like the man. He looked like
the sketch that I had given to the police. His
mannerisms, his voice, his height, his weight--it
all just added up in my mind. And as the evidence
started to come in, it was almost just conclusive
to me that this had been the rapist. And so as
time goes on, I think that my mind would always
see Ronald Cotton.”
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11 years in prison for rape
Exonerated by DNA analysis
*About 75,000 criminal trials per year
are decided on the basis of
eyewitness testimony
*90% of reversed convictions
originally involved mistaken
eyewitness identification.
*Lineup identification procedures
encourage relative judgments.
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“Lineup identification procedures
encourage relative judgments.”
• Eyewitness to a crime on viewing a lineup:
– Oh, my God … I don’t know .. It’s one of those two … but I don’t
know … Oh, man … the guy a little bit taller than number two …
It’s one of those two, but I don’t know.
• Eyewitness thirty minutes later, still viewing the lineup
and having difficulty making a decision:
– I don’t know … number two?
• Officer administering lineup
– Okay
• Defense Attorney, months later at trial:
– You were positive it was number two? It wasn’t a maybe?
• Eyewitness
– There was no maybe about it … I was absolutely positive.
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The Past is How We Remember It
• Daniel Offer asked 67 men in their late
forties:
– Think back to your first year of high school
• Did your parents encourage you to be active in
sports? (40% now) (60% then)
• Was religion helpful to you? (25% now) (70% then)
• Did you receive physical punishment as discipline?
(33% now) (90% then)
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The seven sins of memory
“provide a window on the adaptive strengths of memory”
• Transience
– Weakening or loss of memory over time
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Amnesia is …
• Anterograde
– Inability to create new
memories
• Retrograde
– Inability to remember
previous knowledge
Deficit in memory as a result of brain damage, disease, or trauma.
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Memory declines with age
• Greater deficits across longer intervals
• Greater deficits with distraction
• Mild deficits with simple tasks
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Refresh deficits in the elderly
(Johnson et al., 2004, Psyc. Sci.)
• Older adults are slower
than young adults to think
of an item they just saw
(refreshing just-activated
information)
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Transience: Distraction and Interference
• Distraction
– Prevents rehearsal in
working memory.
• Interference
– Proactive interference
• Disruptive effect of prior
learning on the recall of
new information
– Retroactive interference
• Disruptive effect of new
learning on the recall of
old information
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Medical School (and residency) teaches you how to
be the best doctor under the WORST conditions
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Ways to Address Transience
• Repetition works,
but…
• Elaborate encoding
works better
– More easier to
retrieve info if we
create a larger
number of
associations or
connections to it
water
smell
fire
smoke
Fire Truck
heat
hose
truck
red
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Ways to Address Transience
• Repetition works, but…
• Elaborate encoding works better
• Emotional arousal also helps
– Flashbulb memories
• 40% are inaccurate, but confident.
(Neisser & Harsch, 1992)
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How did you learn about the
jury’s decision?
(Schmolk et al., 2000)
Table 1. Examples of recollections
No distortion: Subject K.V.
Recollection 1 (3 days):
Leaving a 10:00am psych class, my roommate and I heard someone commenting on it, so we asked him the
verdict.
Recollection 2 (15 months):
I first heard the verdict coming out of a lecture with my roommate. The verdict was to be read in the morning
and we had psych during that time. As we left the lecture hall, I heard someone tell a girl next to me that he was
found not guilty. I was stunned and asked him to repeat himself and tell me about the verdict.
Minor distortion: Subject P.H.
Recollection 1 (3 days):
I awoke to screaming outside my apartment window, so I looked at the clock (10:05) and realized the verdict
had just been announced. I stayed in bed and reached for the stereo remote and turned the radio to 100.7 and
listened to the verdict replayed.
Recollection 2 (15 months):
I knew what time the verdict would be read, so I set my stereo to wake me up so I could hear it. I was sitting in
bed and listening to the radio and the screams from the other apartments and outside.
Major distortion: Subject M.G.
Recollection 1 (3 days):
I was in the Commuter Lounge at Revelle [College] and saw it on T.V. As 10:00 approached, more and more
people came into the room. We kept having to turn up the volume, but it was kind of cool. Everyone was talking.
Recollection 2 (32 months):
I first heard it while I was watching TV. At home in my living room. My sister and father were with me. Doing
nothing in particular, eating and watching how the news station was covering different groups of viewers just
waiting to hear the verdict. I think that the focus was mostly on law students and their reactions to the verdict. 20
Ways to Address Transience
•
•
•
•
Repetition works, but…
Elaborate encoding works better
Emotional arousal helps
Encoding specificity
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PRIMING
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Ways to Address Transience
• Repetition works,
but…
• Elaborate encoding
works better
• Emotional arousal
helps
• Encoding specificity
– Context-dependent
memory
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Ways to Address Transience
• Repetition works,
but…
• Elaborate encoding
works better
• Emotional arousal
helps
• Encoding specificity
– Context-dependent
memory
24
Ways to Address Transience
• Repetition works, but…
• Elaborate encoding
works better
• Emotional arousal helps
• Encoding specificity
– Context-dependent
memory
– State-dependent memory
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Ways to Address Transience
• Repetition works, but…
• Elaborate encoding
works better
• Emotional arousal helps
• Encoding specificity
– Context-dependent
memory
– State-dependent memory
– Mood-congruent memory
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Moods and Memories
Tendency to recall experiences that are
consistent with one’s current mood. Emotions, or
moods serve as retrieval cues.
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Discerning True & False Memories
Just like true perception and illusion, real
memories or memories that seem real are
difficult to discern.
© Simon Niedsenthal
When students formed happy or angry memory of
morphed (computer blended) faces (a), they made
the (computer assisted) faces (b) either happier or angrier.
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The seven sins of memory
“provide a window on the adaptive strengths of memory”
• Transience
• Absent-Mindedness
– Breakdown at the interface between attention
and memory that results in failure to
remember information that was never
encoded properly (if at all) or is available in
memory but is overlooked at the time we need
to retrieve it.
• Example: your mind being somewhere else as you
put down your keys
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The seven sins of memory
“provide a window on the adaptive strengths of memory”
• Transience
• Absent-Mindedness
• Blocking
– Inaccessibility of stored information
• Tip of the Tongue
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Tip-of-the-tongue: get other
examples
• Metal or metal-tipped spear used in contests of
distance
• throwing
• Mild or hot, red condiment often used on deviled
eggs
• Inscription on a tomb
• Incombustible, chemical-resistant, material used
for fireproofing
• Heavy, broad-bladed knife or hatchet used
especially by butchers
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The seven sins of memory
“provide a window on the adaptive strengths of memory”
•
•
•
•
Transience
Absent-Mindedness
Blocking
Misattribution
– Assigning a memory to
the wrong source
• Ex: Putting words in
someone else’s mouth
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Source Misattribution/Source
Amnesia
F
• Not a problem when
it’s something benign
• Has tragic
consequences in
other contexts
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The seven sins of memory
“provide a window on the adaptive strengths of memory”
•
•
•
•
•
Transience
Absent-Mindedness
Blocking
Misattribution
Suggestibility
– Memories implanted as a result of leading questions,
comments, or suggestions when a person is trying to
call up a past experience.
• “What time was it when Mr. So and So broke into your
house?”
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Misattribution & Suggestibility Effects
Eyewitnesses reconstruct memories when
questioned about the event.
Depiction of the actual accident.
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Memory Construction
Group A: How fast were the cars
going when they hit
each other?
Group B: How fast were the cars
going when they
smashed into each
other?
A week later they were
asked; Was there any broken
glass? Group B (smashed
into) reported more broken
glass than Group A (hit).
Broken Glass? (%)
50
40
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30
20
14
10
0
Group A (hit)
Group B (Smashed into)
Verb
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Memory Construction
The ALT key study
Kassin & Kiechel, 1996
Helps explain the “false confession” phenomena of prisoners
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Imagining Effects
• Repeatedly imagining nonexistent actions
and events can create false memories
– Fake memories feel like real memories
– Occurs because visualizing something and
actually perceiving it activate similar brain
areas
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Hippocampus & Misattribution
• Hippocampus did not
distinguish True from
False memories during
retrieval.
• Parahippocampal gyrus
activity can distinguish
True from False
memories during
retrieval.
(Cabeza, Rao, Wagner, Mayer, & Schacter, 2001)
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Constructed Memories
• Danger of creating false
memories of child abuse.
• Children are particularly
susceptible.
– What happened? (9%
distortions)
– Where did you hurt
yourself? (49% distortions)
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Ceci Video demonstrates
suggestibility in children
NOTE/WARNING: This video contains triggers.
http://video.google.com/videoplay?docid=-1262410204090315491#
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Retrieval Failure
• Eyewitness testimony
– Repeated questioning of
specific aspects of an
event may impair other
unquestioned aspects of
the incident.
• Sexual abuse
– Temporary forgetting is
more common when a
family member is the
perpetrator.
– Nontraumatic, positive
memories inhibit negative
memories.
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The seven sins of memory
“provide a window on the adaptive strengths of memory”
•
•
•
•
•
•
Transience
Absent-Mindedness
Blocking
Misattribution
Suggestibility
Bias
– Powerful influences of our current knowledge
and beliefs on how we remember our pasts.
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Bias
• The way we were depends on the way we
are
• Relationships
– If your current view of your partner is
negative, the more negative your memories
are of them, which only further confirms your
negative attitudes.
– Couples who stayed together for more than
four years recalled that the strength of their
love had grown.
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The seven sins of memory
“provide a window on the adaptive strengths of memory”
•
•
•
•
•
•
•
Transience
Absent-Mindedness
Blocking
Misattribution
Suggestibility
Bias
Persistence
– Repeated recall of disturbing
information or events that we
would prefer to banish from
our minds. Ex: flashbacks
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Forgetting
Inability to retrieve information, due to
poor encoding, storage or retrieval.
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Forgetting…it’s a good thing!
Jill Price
http://www.youtube.com/watch?v=SoxsMMV538U
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Why do we forget?
Forgetting can occur at
any memory stage; we
filter, alter, or lose
much information
during these stages.
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Encoding Failure
Much of what we are exposed to, we never notice.
We cannot remember what we did not encode.
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Encoding Failure
1. The standard telephone dial has ten numbers, one through nine plus zero.
However, it doesn’t have all 26 letters of the alphabet. Which ones don’t
appear on the dial?
2. What is the color of the top stripe of the American flag? The bottom stripe?
How many red and how many white stripes does it have?
3. If you have a watch with mechanical hands, cover the face and try to recall
what it looks like. How many numbers does it have? Are they Arabic or
Roman numerals—or does it have any numbers at all?
4. Most wooden pencils are not round. How many sides do they typically
have?
5. In what hand does the Statue of Liberty hold her torch?
6. The White House is pictured on the back of a $20 bill. What is on the back
of a $10 bill? A $5 bill? A $1 bill?
7. What four words besides “In God We Trust” appear on most U.S. coins?
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Encoding Failure
1. The standard telephone dial has ten numbers, one through nine plus zero. However,
it doesn’t have all 26 letters of the alphabet. Which ones don’t appear on the dial?
(“Q” and “Z”)
2. What is the color of the top stripe of the American flag? (Red) The bottom stripe?
(Red) How many red and how many white stripes does it have? (seven red and six
white)
3. If you have a watch with mechanical hands, cover the face and try to recall what it
looks like. How many numbers does it have? Are they Arabic or Roman numerals—or
does it have any numbers at all?
4. Most wooden pencils are not round. How many sides do they typically have? (Six)
5. In what hand does the Statue of Liberty hold her torch? (Right)
6. The White House is pictured on the back of a $20 bill. What is on the back of a $10
bill? (Treasury Building) A $5 bill? (Lincoln Memorial) A $1 bill? (The word “One”)
7. What four words besides “In God We Trust” appear on most U.S. coins? (United
States of America)
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Storage Decay
Poor durability of stored memories leads to their decay.
Ebbinghaus
showed this with
his forgetting
curve.
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Retrieval Failure
Although the information is retained in the
memory store it cannot be accessed.
Tip-of-the-tongue (TOT) is a retrieval failure
phenomenon. Given a cue (What makes the blood
cells red?) the subject says the word begins with an H
(hemoglobin).
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Motivated Forgetting
Motivated Forgetting:
People unknowingly revise
their memories.
-Ex. Compulsive gamblers frequently recall losing less
money than is actually the case
Culver Pictures
Repression: Defense
mechanism that banishes
anxiety-arousing thoughts,
feelings, and memories from
consciousness-is more
automatic and unconscious.
Sigmund Freud
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