Memory
Bartlett’s war of the ghosts
Conclusion: we recall not the literal text, but the mental model we constructed
from it.
Remembering: involves reconstructing past events using presently existing
schemes.
Newly encoded information undergoes modifications and changes as the result
of interactions with information already in memory and through
reinterpretations of existing data forced by the acquisition of subsequent
knowledge.
Progressive changes happen in interpretation and evaluation as the target
information interacts with relevant information, either existing or acquired
later, in the knowledge base.
First time parking at a lot (e.g., in a mall) you will easily find your car. After
parking there many times, you get confused.
Number of trials (or experiences) has contrastive effects on episodic and
semantic memories. Increased experience with any particular event class
increases semantic (or general knowledge) about the event and its context.
Increased experience with similar events, makes specific knowledge
increasingly confusible, and ultimately episodes cannot be distinguished.
Loftus & Palmer (1974)
How accurately do we remember the details of a complex event, like a traffic
accident, that has happened in our presence? How well do we do when asked
to estimate some numerical quantity such as how long the accident took, how
fast the cars were moving, or how much time elapsed between the sounding of
a horn and the moment of collision?
Tendency to overestimate the duration of complex events;
Marshal (1969): air force personnel knowing they would be questioned on the
speed of a car estimated it from 10 to 50 mph- the car was going only 12 mph.
Study 1: shown films of traffic accidents, then questions about them
“About how fast were the cars going when they
hit/smashed/bumped/collided/contacted each other?
Smashed: 40.8 (mean speed estimate), collided: 39.3, bumped: 38.1, hit:
34,contacted: 31.8
Study 2: 150 students shown film of multiple car accident (less than 1 min)
followed by questions. One question asked about the speed of the cars. 50 were
asked “About how fast were the cars going when they
smashed and 50 when they hit each other. 50 not asked about speed. 1 week later,
answered new questions. Critical one: Did you see any broken glass?
Smashed: 16 yes, 34 no; Hit: 7 yes, 43 no; control: 6 yes, 44 no.
“Two kinds of information go into one’s memory for some complex occurrence.
The first is information gleaned during the perception of the original event, the
second is external information supplied after the fact. Over time, information from
those two sources may be integrated in such a way that we are unable to tell from
which source some specific recalled. All we have is one memory.”
Flashbulb Memories
(Neisser 1982)
Impressive consistency to the organization of such memories:
•Place
•Ongoing activity
•Informant
•Aftermath
•One’s own affect and that of others
At first glance, FB memories appear to be obvious illustrations of a commonsense
principle: people remember what is important
Problem: Actual content of FB memories does not meet that criterion
“The fact of JFK’s death may be important but what difference does it make who
told me about it, or where I was when I heard the news?”
Why do we remember such things?
Brown and Kulik: ‘Now Print’ mechanism in the brain that triggers whenever we
believe that an important (consequential) event takes place.
Supposedly, this mechanism ‘prints’ the whole event into a permanent record for
later. This hypothesis implies:
A) FB memories are accurate
B) The process by which FB memory is created occurs at the time of the event
C) Surprise, emotionality, and similar reactions are closely related to the
consequentiality of the event, and that higher levels of surprise and
emotionality lead to good memory
D) Common characteristics among different FB memories reflect the common
characteristics of an underlying neural mechanism
All these implications deserve careful scrutiny
Accuracy of FB memories
Vivid recollection and accurate testimony may be wrong
Neisser: “For many years I have remembered how I heard the news of the Japanese
attack on Pearl Harbor, which occurred on the day before my thirteenth birthday. I
recall sitting in the living room of our house- we only lived in that house for one
year, but I remember it well- listening to a baseball game on the radio. The game
was interrupted by an announcement of the attack, and I rushed upstairs to tell my
mother. This memory has been so clear for so long that I never confronted its
inherent absurdity until last year: no one broadcasts baseball games in December!
(It can’t have been a football game either: professional football barely existed in
1941, and the college season ended by Thanksgiving).
FB memories can be as wrong as other kinds of memory; they are not produced by
a special quasi-photographic mechanism.
When are FB memories established
Memories become FB primarily through the significance that is attached to
them afterwards.
Endurance, not immediate survival is the question.
We can all give good accounts of what happened earlier today.
FB moments are sure to be pondered, discussed, and redescribed on
subsequent occasions.
Hypothesis: persistence is due to the frequent- rehearsals- reconsideration
they receive.
Emotionality
Emotional experiences are not especially well remembered
High levels of arousal narrow the focus of attention; they unlikely promote
detailed recall of circumstances.
Structure of the Memories
Resemble narrative conventions
In our culture we all know how to tell a story (who, what, when, where, and why)
“The flashbulb recalls an occasion when two narratives that we ordinarily keep
separate – the course of history and the course of our own life- were momentarily
put into alignment.
We remember the details of a flashbulb because those details are the links
between our own histories and History.
Frequent rehearsal and discussion contribute to the accuracy.
The term flashbulb is misleading; these are not momentary snapshots as enduring
benchmarks.