Transcript Episodic Memory

Episodic Memory
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Life events are stories about yourself.
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That is, they are structured in memory in
the same manner as all stories.
Memory for events in your own life are
also called autobiographical
memory.
Episodic Memory
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Updating Memory
Accuracy and Confidence in Event
Memory
Long-term Retention
Autobiographical Memory
Episodic Memory
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Updating Memory
Accuracy and Confidence in Event
Memory
Long-term Retention
Autobiographical Memory
What day is it today? What day was it
yesterday? What day will it be tomorrow?
Noon
3
Seconds
2.5
2
Today
Yesterday
Tomorrow
1.5
1
0.5
0
Sun
Mon
Tues
Wed Thurs
Days
Fri
Sat
Noon versus Morning
3
2.5
2
Today
Yesterday
Tomorrow
1.5
1
0.5
0
Sun
Mon
Tues
Noon
Wed
Thurs
Fri
Sat
Morning
3
2.5
2
Today
Yesterday
Tomorrow
1.5
1
0.5
0
Sun
Mon
Tues
Wed
Thurs
Fri
Sat
Noon versus Morning versus Evening
3
3
2.5
2.5
2
Today
Yesterday
Tomorrow
1.5
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2
Today
Yesterday
Tomorrow
1.5
1
0.5
Noon
0.5
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Sun
Mon
Tues
Wed
Thurs
Fri
Morning
0
Sat
Sun
Mon
Tues
Wed
Thurs
Fri
Sat
4
3.5
3
2.5
Today
Yesterday
Tomorrow
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1.5
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0.5
Evening
0
Sun
Mon
Tues
Wed
Thurs
Fri
Sat
Orienting to Time and Place
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Cues are determined by a person’s
current plans and expectations
The set of cues are continually being
updated.
This keeps us oriented to time and
place
Episodic Memory
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Updating Memory
Accuracy and Confidence in Event Memory
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Role of Post-Event Information
Effect of intentions on event memory
Effect of questioning on confidence and accuracy
Relationship between accuracy and confidence in
event memory
Long-term Retention
Autobiographical Memory
Memory for Facts versus
Memory for Events
Task Read a story and recall it some time later
Memory Group asked to recall story
Interactive Group asked to think about and react to story
After they have read the story subjects told either consistent (+),
inconsistent (-), or no (0) information with respect to the story
Number of Subjects Producing Recall Errors (Out of 20)
2 Days
Group 0 + Mem 0 1 0
Inter 0 0 4
3 weeks
0+101
2 2 13
6 weeks
0+112
3 3 12
Sad Ending-Married Comment
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Sad Ending
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Margie was horrified. She had always wanted to
be a mother and had her heart set on having
many children. They argued bitterly over what
had become a very serious problem for them. A
long discussion of the status of their relationship
followed.
Recall
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They separated but realized after discussing the
matter that their love mattered more.
The discussed it and decided they could agree on
a compromise: adoption.
Happy Ending-Not Married
Comment
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Happy Ending
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Margie was elated. Because she wanted to have a
career she had also felt that she didn’t want to
have children. They rejoiced in the dissolution of
what would have been a very serious problem for
them. Along discussion of the status of their
relationship followed.
Recall
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There was a hassle with one or the other’s
parents.
They disagreed about having children.
Conclusion
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It is possible to remember a story
accurately over a long retention
interval.
However, normal autobiographical
memory is subject to constant revision.
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Memories of specific episodes may change
over time as the result of post-event
information
Intentions As Recall Cues
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Marcia Johnson:
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Found that it is more difficult to distinguish
between:
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Than:
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Saying something vs. thinking about saying it.
Saying something vs. hearing it.
This and other studies by Johnson
support the important role of intentions
and action in organizing memory.
The Effect of Post-Event Questioning
on Confidence and Accuracy
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Children are especially susceptible to postevent information; the response to a
repeated yes/no question will change
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Loftus and Pickerel (1995).
Even eye-witness testimony may be
influenced by post-event information
Successive recall attempts under hypnosis
increases confidence must more than
accuracy
Memories Disputed Between Twins
(Sheen, Kemp, & Rubin, 2001)
Age
at
Test
21
Age
Cue Word
at
Event
Description of Memory
11
Fair
21
14
Restaurant
Who came in 12th in
international cross
country race
Who went for lunch with
their mum and had a
worm in her meal
21
12
Boat
Who was in boat with
father when they saw a
tiger shark
Episodic Memory
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Updating Memory
Accuracy and Confidence in Event
Memory
Long-term Retention (of School Years)
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Personal Information
Academic Information
Autobiographical Memory
Very Long Retention Intervals
Very Long Term Retention of
Personal Information
Very Long-Term Retention of
Academic Information
Episodic Memory
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Updating Memory
Accuracy and Confidence in Event
Memory
Long-term Retention
Autobiographical Memory
Constructing Autobiographical
Function
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Use cue word method to probe
memory.
Record the age at which each event
occurred.
Number of Memories Per
Decade
Autobiographical Retention
450
400
350
300
250
200
150
100
50
0
61-70
51-60
41-50
31-40
21-30
11-20
Age of Subjects at Time of Event
1-10
Autobiographical Memory
A retention function for old memories has three
main features:
 Recency: Older memories are less likely to be
recalled than more recent ones
 A reminiscence bump consisting of a
surprisingly large number of memories
coming from ages 10-30, particularly between
15 and 25
 Childhood amnesia for the first five years of
life
Episodic Memory
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Updating Memory
Accuracy and Confidence in Event
Memory
Long-term Retention
Autobiographical Memory
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Early childhood amnesia
Early Childhood Amnesia
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Pillemer, Picarello, and Pruett (1994):
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Memory for an emergency school evacuation.
3 yr-olds vs. 4 yr-olds.
Two weeks after the event:
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Same level of memory for event.
Seven years later, forced-choice recognition test:
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3 yr-olds (now 10): No recognition.
4 yr-olds (now 11): 86% correct.
Episodic Memory
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Updating Memory
Accuracy and Confidence in Event
Memory
Long-term Retention
Autobiographical Memory
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Early childhood amnesia
Reminiscence bump
Reminiscence Bump
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A total of 93% of vivid life memories
are either unique events or first-time
experiences
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Hence novel and emotional experiences
When alumni were asked to recall 4
memories from their first year of college
more than 20 years previously, 41% of
September
the memories came from
The Effect of Novelty and
Emotion on Retention
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Novel events attract more rehearsals,
which results in longer retention
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Von Restorff Effect
Primacy Effect
Emotional events are specially encoded
so that they are difficult to forget
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Cahill & McGaugh
Episodic Memory
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Updating Memory
Accuracy and Confidence in Event Memory
Long-term Retention
Autobiographical Memory
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Early childhood amnesia
Reminiscence bump
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Effect of novelty and emotion on accuracy and
confidence
Flashbulb Memories
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Vivid memories for unexpected
emotional events, e. g., Kennedy
assassination; Challenger explosion.
Despite the vividness of such memories
they may be highly inaccurate. So
confidence is not highly correlated with
accuracy
Flashbulb Memories Studies
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Neisser and Harsch (1992):
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Challenger explosion.
40% of the memories changed after 2.5 years.
Schmolck, Buffalo, and Squire (2000):
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O.J. Simpson verdict.
42% of memories distorted after 2.5 years.
61% of distorted reports were remembered with
high degree of confidence.
Post Traumatic Stress Disorder
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Vivid memories of unexpected, tragic,
hence highly emotional events may
disrupt attention to current events.
Memories can not be easily forgotten or
removed from consciousness
However, no evidence that memories
are more accurately remembered than
other memories