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8/10/2019 McCloskey Wible Cohen (1988)
1/11
Journal
o
Experimental
Psvchology:
General
1988 Vol. 117,No. 2,
171-'l81
Copyright 1988hythe Am :anPsychological Association, Inc.
OD96-3445/88/$00.75
Is
There a Special Flashbulb-Memory Mechanism?
Michael McCloskey, CynthiaG.
Wible,
andNealJ.Cohen
Johns
Hopkins
University
Many people
reportvivid
recollections
of thecircumstancesin which they
learned
of
major
events, suchas theassassinationofPresident Kennedy,or theassassinationattempton President
Reagan. Brown and Kulik (1977) argued that
this
phenomenon, which they labeledflashbulb
memory,implies
the
existence
of a
special memory mechanism that creates
a
detailed, permanent
record of the individual's experience when triggered by an event exceedingcriterial levelsof
surprise and consequentiality. In this article we evaluate the special-mechanism hypothesis,
arguingon empirical and logical grounds that the flashbulb-memory phenomenon does not
motivate the
postulation
of a special flashbulb-memory mechanism. We suggest instead that
flashbulbmemories should be viewed as
products
of
"ordinary"
memory mechanisms, and hence
as phenomenathatmayoffer insights into the nature of these mechanisms.
Where were youwhenyou learned of the assassination of
John F. Kennedy, the shooting of Ronald Reagan, or the
explosion of the space shuttle
Challenged
How did you hear
about
the event? What were you doing at the time? What
were your first thoughts upon hearing the news? Many people
report
that
they
can
remember
vividlythe
circumstances
in
whichthey learned of certain major public or personal events,
afeatof memory that has intrigued researchers since at least
the turn of the century (e.g., Brewer, 1986; Brown & Kulik,
1977;Colegrove,
1899; Linton, 1975; Neisser, 1982, 1986a,
1986b; Pillemer,1984;Rubin & Kozin, 1984; Thompson &
Cowan, 1986; Winograd&
Killinger,
1983;
Yarmey
&
Bull,
1978).
Brown
and Kulik(1977)suggested that this phenomenon,
whichthey labeledflashbulb memory, implies the existence
ofaspecial memory mechanism. They argued thatthespecial
mechanism, when triggered
by an
event exceeding criterial
levels of surprise and consequentiality, creates a permanent
record of the contents of awareness for the period immediately
surrounding
the
shocking experience.
The
special-mechanism
hypothesis has been the subject of considerable discussion in
recent years, with some authors endorsing
the
hypothesis
and
others noting potential problems. Pillemer
(1984),
for exam-
ple, argued
in
favor
of the
hypothesis
on the
basis
of
data
concerning subjects' recollections of the circumstances in
which they learned about
the
assassination attempt
on
Presi-
dent Reagan. In contrast, Neisser(1982)raised doubts about
the accuracy of flashbulb memories, and also pointed out
problems with several other aspects of the Brown and Kulik
hypothesis. Furthermore, Rubin and Kozin(1984)questioned
whether the
characteristics
of flashbulb memoriesclearlyset
these memories apartfromother autobiographical memories.
Although
a number of important issues
have
been raised,
itremains unclear whether the flashbulb-memory phenome-
We thank Roberta
Goodman-Schulman,
Kathi Hirsh, Brenda
Rapp,Scott Sokol,and Molly Treadway for theirhelpfulcomments.
Wealsothank the Cognitive Lunch group for an illuminating discus-
sion.
Correspondence concerning this article should be addressed to
Michael McCloskey, Cognitive Science Center,
Johns
Hopkins Uni-
versity, Baltimore, Maryland21218.
non warrants the postulation of a special flashbulb-memory
mechanism. One reason is that no detailed, coherent
formu-
lation
of a special-mechanism hypothesis has been set forth.
The hypothesis as stated by Brown and Kulik
(1977)
and
discussed
in
subsequent articles
is
underdeveloped
in
several
crucial respects,
and
there
is
also considerable variation
be-
tween
and
evenwithinarticles
in
what
is
claimed about
the
mechanism and the memories it produces. A related problem
isthat discussions
of the
special-mechanism hypothesis have
oftenfailedto engage the critical issue ofwhatwould consti-
tute
a
sufficientbasis
for
positing
a
special
flashbulb-memory
mechanism.
As
a consequence of these problems, the implications of
the evidence and arguments presented in studies of
flashbulb
memory have not
always
been clear. For example, Neisser
(1982)
reported
two
examples
of
inaccurate flashbulbmem-
ories in support of his argument that these memories are not
necessarily veridical. Thompson and Cowan (1986), however,
presented evidence that for one of Neisser's examples the
inaccuracy is relatively minor, and concluded that this ex-
ample does not challenge the
"basic
accuracy of flashbulb
memories"(p.
200). Neisser
(1986b), in a
reply
to
Thompson
and
Cowan, disagreed with their conclusions.
Unfortunately,
the
exchangefails
to
clarifywhat implications
any
particular
degree
of
inaccuracy
has for the
special-mechanism hypothe-
sis. Do afewexamples of minor inaccuracy call the hypothesis
into serious question? Or does the hypothesis remain unchal-
lengedif the accounts are usually basically accurate ?
In
this
articleweattempttoevaluatethespecial-mechanism
hypothesis systematically and, more generally, to assess the
implicationsof theflashbulb-memory phenomenonforthe-
ories
of
memory.
On the
basis
of
data
and
arguments,
we
conclude
that the postulation of a special flashbulb-memory
mechanism
is unwarranted. Instead, we suggest, flashbulb
memories' should be viewed as products of
"ordinary"
auto-
biographical memorymechanisms,
and
hence
as
phenomena
that mayofferinsights into the nature of these mechanisms.
1
We
willuse the
term
flashbulb memoryin a theoretically neutral
sense, to refer to individuals' recollections of the circumstances in
which they
learned
about surprising and consequential events. It
should
be
understood that
our use of
this term does
not
imply
anythingabout the memory processes underlying the recollections.
8/10/2019 McCloskey Wible Cohen (1988)
2/11
172
M.
McCLOSKEY, C. WIBLE, AND N.
COHEN
The Special-Mechanism Hypothesis
Underlying
the
hypothesis
of a
special
flashbulb-memory
mechanism is the following implicit argument: Flashbulb
memories have
specialcharacteristics,
that
is,
characteristics
different from thosethememories would haveiftheywere
producedby ordinary memory mechanisms. These
special
characteristics imply
that the
memories
are
products
of a
special memory mechanism.
Thus, in evaluating the special-mechanism hypothesis, we
must consider
the
followingquestions: What claims does
the
hypothesis
make
about
the characteristics of flashbulb mem-
ories?
To
what extent
are
these claims warranted
by the
available evidence? And, if these claims are accepted, do they
clearly
distinguish
flashbulb
memoriesfrom"ordinary"mem-
ories and therefore warrant thepostulationof a special flash-
bulb-memory mechanism?
Characteristics of Flashbulb Memories
Statements
of the
special-mechanism hypothesis
are not
entirely clear with regard to the characteristics of flashbulb
memories,
at
timespressing strongclaimswhile
at
other times
qualifying
these claims. As a starting point for discussion, we
will
consideroneparticular interpretationof theBrownand
Kulik (1977) hypothesis, an interpretation that makes strong
claimsabout thecharacteristics of flashbulbmemories.On
this rendering the special flashbulb-memory mechanism,
when triggered by
criterial
levels of surprise and consequen-
tiality,createsinmemoryadetailedandpermanent recordof
the individual's experience immediately before, during, and
immediatelyafterlearning of the shocking event.
(Brown
and
Kulik, 1977, p. 87, stated that the mechanism records all
"brainevents above some leveloforganization, apparently
meaning something like
the
contents
of
awareness, including
such information as where the individual was, what he or she
wasdoing, etc.)
The
representations created
by the
special
mechanism are
complete, accurate,vivid,
and
immune
to
forgetting(i.e.,thestored information,in itsoriginal veridical
form,remains permanently accessible).
One could certainly formulate weaker interpretations of
Brown and
Kulik's
(1977) position (e.g., flashbulb memories
are impressively, although not perfectly, complete, accurate,
vivid,and resistant toforgetting). However,weconsider the
strong claims
first
because these claims,
if
supportable, would
make the most convincing case for the position thatflashbulb
memoriesare soremarkable that aspecial memory mecha-
nism must be posited to account for them. If the strong claims
prove untenable, we can then consider whether weaker claims
motivate
the
postulation
of a
special
flashbulb-memory
mech-
anism.
2
We begin our evaluation of the strong claims about char-
acteristicsof flashbulbmemoriesbyreportingastudy aimed
atevaluating these claims.
Flashbulb Memories for the Explosion
ofthe
Space Shuttle
With one exception (Pillemer, 1984),studiesof flashbulb
memories (Brown & Kulik, 1977;Colegrove, 1899; Winograd
&
Killinger, 1983; Yarmey&Bull, 1978) have probed sub-
jects'memories
for the
circumstances
in
which they learned
of
an eventonlyonce, long
after
the event. Yet,asNeisser
(1982)
has pointed out, this procedure does not permit the
accuracyof the subjects' reports to be assessed. Moreover, it
is
difficult
to determine whether the amount of remembered
information
remains constant over time,
as it
should
if flash-
bulb
memories are immune to forgetting, or whether subjects'
memories instead become less detailed and complete as time
passes.
Potentially more informative
is a
procedure
in
which
sub-
jects are questioned twice, once shortly
after
a surprising,
consequential event, and again some time later, as in
Pille-
mer's
(1984) study concerningtheReagan assassination at-
tempt. The two sets of responses may then be compared with
regard to amount and consistency of
information
reported on
the two occasions. The explosion of the space shuttleChal-
lengeron January 28, 1986, tragically provided the opportu-
nityto carry out a study of this sort. The flight of
Challenger
washighlypublicized because the crew included the teacher
Christa McAuliffe. Furthermore, the explosion was com-
pletelyunexpected and had important consequences for the
space program and, more generally, for public confidence in
government, science,and technology. Thus, with regard to
surprise and consequentiality, the presumed triggering con-
ditions for the special flashbulb-memory mechanism, the
shuttle explosion appears comparable to the events used in
previous studies of flashbulb memory (e.g., the Reagan assas-
sination attempt, assassinations
of
other political leaders).
Indeed, the disaster was widely described in the media as one
of those events for which people remember where they were
and
what they were doing when they learned
of it. In the
present studyweprobed subjects' memoryforcircumstances
of
learning about the shuttle explosion a few days
after
the
explosion,andagain9months later.
Method
Questionnaire. The questionnaire presented to subjects included
four
questionsabout the circumstances under which the
respondent
learned of the explosion of thespaceshuttleChallenger:
1.
Where were you when you first learned of the explosion?
2
It might be suggested that thestrong
claims
we have formulated
about
characteristics
of flashbulb
memories
are
stronger than Brown
andKulik
(1977)
intended. For example, whereas thestrongclaims
characterizeflashbulbmemoriesascomplete recordsof the
individ-
ual's experience around the time of learning about a surprising,
consequential
event, Brown and Kulik (1977, pp.74-75,85)
stated
thatflashbulbmemories varyin"elaboration,"suggestingthatunder
some circumstancesthese memories could be less than complete.
However, Brown
and
Kulik also repeatedlyassert(e.g.,
see
Brown
&
Kulik, 1977,pp. 76,
95-96)
thatthe flashbulb-memorymechanism
recordsallrecent brain events. Thus,potentialconflicts betweenthe
strong claims we have formulated andstatementsmade by Brown
and Kulik
reflect
ambiguities in their claims. In any event, regardless
ofwhat Brown
and
Kulik intended,
it is
important
to
consider strong
claims aboutcharacteristics
of flashbulb
memories because,
as
stated
earlier, these claims wouldprovidethe firmestbasisfor assertingthat
flashbulb
memories
arevery
different from
ordinary memories.
8/10/2019 McCloskey Wible Cohen (1988)
3/11
FLASHBULB MEMORY
7
2. What were you doingwhenyou first learned of the explosion?
3.Did you see theeventat thetimeit wasactuallyhappening,or
did you
learn
aboutit
later?
If
later,
how did you
learn about
it?
4. Whatwereyour first thoughts upon hearing the news?
We will
referto
these
items
collectively
as the
circumstances ques-
tions,andindividuallyas thelocation, activity, source,andreaction
questions, respectively.
For
each question subjects were asked
to
rate
theirconfidence in the correctness of their answers on a scalefrom1
(lowconfidence)
to 7
(high confidence).
The four
circumstances questions were intended
to
probe cate-
gories
of
information that should
be
included
inmemories
generated
byamechanism that recordsthecontentsofawarenessfor theperiod
immediately surroundingthelearning aboutasurprising, consequen-
tial event. Previous studies have focused
on six
canonical
categories"
of information: place, ongoing event, information, own
affect,
affect
in others, and aftermath (see, e.g., Brown &
Kulik,
1977;
Pillemer,
1984).Ourlocation, activity,andsourcequestions closely correspond
to the first
three
of
these categories, respectively,
and our
reaction
question
corresponds roughly
to the ownaffect
category.
We did not
probe affect
in others or aftermath, because information in these
categoriesmay notalwaysbeavailableto berecorded,atleast within
the span
of
time over which
a
special
flashbulb-memory
mechanism
wouldoperate.For
example,
a
person
who
heard
aradio
announce-
ment about the shuttle explosion while alone might have no experi-
ence
ofaffect in
others
to
remember.
The questionnaire alsoincluded
a
single question about
the re-
spondent's memory for his or her whereabouts at the time of the
assassination
attempt
on President
Reagan.
Thesefive
critical questions (the
four
shuttle circumstances ques-
tions
and the
single question about
the
Reagan assassination attempt)
occurred
in
identicalform
on
both
theinitialand
9-month question-
naires. Instructions
on
both questionnaires stressed that answers
should
be as
specific
as
possible.
Both questionnaires also included several additional questions,
most
of
which concerned
the
sources
from
which
the
respondent
obtained information
about
the
shuttledisaster
subsequent
to
initially
learning about it, and the details of theshuttleflightitself.The results
for
these questions are not relevant for our purposes and therefore
will
not be
discussed.
Design
and
procedure.
On January 31, 1986, three days
after
the
explosion, questionnaires were distributed
to 50
faculty,postdoctoral
fellows,graduate
students,
undergraduate students, and support
staff
associatedwith
the
Psychology Department
of
Johns Hopkins Uni-
versity.
Forty-five of these"immediate"questionnaires (90%) were
returnedwithin 1 week of the shuttle disaster.
On October 21,1986,approximately 9 months
after
the explosion,
follow-upquestionnaires were distributed
to the 29
subjects
who (a)
had returned the
immediate
questionnaire
within
1
week
of the
explosion
and (b)
were still available
at the
time
of the
follow-up.
Twenty-seven subjects (93%) completed the 9-month questionnaire.
These subjects
willbe
referred
to as the
repeated
testing
group.
To
assess
effects
of
completing
the
immediate questionnaire
on
responses givenat 9months, the 9-month questionnaire wasalso
distributed to 35 individuals who had not received the immediate
questionnaire. Thirty-one (89%) completed
the
questionnaire. These
subjects
willbe
referred
to as the
9-month-only
group.
Results
Answers
to the
location, activity, source,
and
reactionques-
tions
werefirst
scored
simplyas
substantive
or"don't
remem-
ber responses. Aresponsewasscored assubstantive if it
provided
an
answer
to the
question,even
if the
response
was
nothighly specific.For
example,
at
work
aswellas
Lever-
ingHallnext to the
news
stand wasscoredas asubstantive
answerto thelocationquestion.This scoring criterion appears
to be consistentwith those
used
in previous studies
(e.g.,
Brown &
Kulik,
1977; Pillemer, 1984)toassesswhethera
subjectprovidedinformation
in a
canonicalcategory.Because
some subjects reported
information
relevantto one of the
circumstancesquestionsin an
answer
to another ofthese
questions,
thescoringforeachquestion took accountof any
relevant
information the
subjectprovided
in answers to
other
questions.
Nine-month responses.Table 1presents,for the repeated
testing
subjects
on the immediateand 9-month question-
naires, and for the
9-month-only
subjectson the9-month
questionnaire,theproportionof
subjects
whoofferedsubstan-
tiveresponsestoeachof thecircumstances questions. From
the9-month results,it isclear thattheexplosionofChallenger
is an
event
for which the flashbulb-memory
phenomenon
occurs:9months
after
the
shuttleexplosion
most subjects
could providereports concerningwhere
they
were,
what they
weredoing,howtheyheard,and how
they
reactedwhenthey
learnedof thedisaster.
All
subjects
inboth groups
gave
substantive answersto at
leasttwo of thefour
questions;
22 of the 27
repeated-testing
subjects(81%)and 26 of the 31
9-month-only subjects(84%)
gave substantive
responses
to all
fourquestions. Subjects
were
also
highlyconfident
abouttheirresponses. Acrossthe
four
circumstances
questions,mean confidence forsubstantive
answers was 6.13 (on a
scale
with 7 as the
highest
confidence
level) for the
repeated-testinggroup,
and
6.16
for the
9-month-
only
group.
Brown
and
Kulik (1977)
scored a
subject
as
having
a
flashbulb
memory
for an
event
if the
subject
(a) answered
yes
to the
question,
Do yourecall the
circumstances
in
whichyou first heard
that
[event]? , and (b)
provided
infor-
mation in at least one of the sixcanonical
information
cate-
gories
inreporting these circumstances.Assuming that any
subject
who
gave
asubstantive responseto one ormoreof
ourcircumstances questions
would
have givena yes answer
to aquestionof theform Do you recall the circumstances in
which
you firstheard thatthespace shuttleChallengerhad
exploded? , thenby the
Brown
and
Kulik
criteriaall of our
repeated-testing
and 9-month-only subjects
have
flashbulb
memories for thespace shuttle explosion.
Table
1
Proportion o Repeated
Testing
and
-Month-Only
Subjects
ProvidingSubstantiveResponses to the Circumstances
Questions on theImmediateand9-Month Questionnaires
Repeated testing
Question
Location
Activity
Source
Reaction
Immediate
questionnaire
1.00
1.00
1.00
.96
9-month
questionnaire
.96
.89
1.00
.89
9-month
only
9-month
questionnaire
.94
.87
1.00
.97
.99
.94
.94
8/10/2019 McCloskey Wible Cohen (1988)
4/11
74
M.
McCLOSKEY,
C. WIBLE, AND N. COHEN
Comparison
of the
9-monthresults
for the
repeated-testing
group and the
9-month-only
group suggests that completing
the immediate questionnaire had little if anyeffecton the 9-
month responses of the repeated-testing group. The mean
number of
questions answered substantively
was
3.74 (out
of
4) for the
repeated-testing group
and
3.77
for the
9-month-
only
group, t < \. Furthermore, confidencedid not
differ
across groups (see earlier results on confidencelevels).
Comparison ofimmediateand 9-monthresponses.The 9-
month
results
paint a seemingly impressive picture of subjects'
abilityto remember the circumstances in whichtheylearned
of the
shuttle explosion. However, comparison
of the
9-month
responses with those given shortly
after
the explosion
reveals
that
the
amount
of
stored information subjects could access
decreased over the retention interval, and further that the
immediate and 9-month responses were not always consistent.
For
each
of the 107
circumstances questions answered
substantively on the immediate questionnaire (27 subjects
times 4 circumstances questions, minus a single reaction
question answered "don't remember ),
two
independent
judges compared the immediate response with the corre-
sponding 9-month response.
A
9-month response was scored as the
same
as the corre-
sponding immediate response if it provided basically the same
information(although not necessarily in the same wording).
A
relativelylaxcriterion was applied, so
that,
for example,
theresponses
"reading"
and studying to theactivity ques-
tion
were scored
as the
same.
A9-month response
was
scored
as
morespecific than
the
immediate response if it was not inconsistent with the im-
mediate response, but answered the question at afiner level
of
detail,
or
included particular pieces
of
information
not
reportedon the immediate questionnaire. Forexample,the
9-month response eating lunch (actually, drinking coffee)
with
S S , S D , and M M "to the
activity question was scored as morespecificthan the imme-
diate response eating lunch with some friends.
Similarly, a 9-month response was scored as
moregeneral
than thecorresponding
immediate response
if it was not
inconsistentwiththe immediate response, but was less spe-
cific,
or
omitted particular details.
For
example,
the
9-month
response word of mouth was scored as more general than
the immediate response heardC talking about it.
A9-month responsewasscoredasinconsistentif itcontra-
dicted
the
corresponding immediate response
in
some (al-
though
not necessarily all) respects. For example, the 9-month
response
at my
desk
to the
location question
was
scored
as
inconsistent with the immediate response walking out of the
door toward
B 's
office.
Finally,
a 9-month response was scored asdon'tremember
if
the question was answered substantively on the immediate
questionnairebutgivena"don'tremember responseon the
9-month questionnaire.
The two judges agreed on 86% of the initial classification
decisions. Disagreements were resolved through discussion.
For some ambiguous responses, the subject was consulted for
clarification.
For example, one subject indicated that the 9-
month response examining somedata for an experiment
did not
refer
to thesame activity as theimmediate response
Table 2
ComparisonofImmediateand 9-MonthResponsesfor
Repeated-Testing Subjects
Relationship of 9-month response to
immediate
response
Question
Location
Activity
Source
Reaction
Total
Same
21
15
16
13
65
More
specific
3
2
7
More
general
2
4
7
7
20
Inconsistent
2
4
2
9
Don't
remember
3
0
2
6
designing
an
experiment. Table
2
presents
for
each
of the
fourcircumstances questionsthenumberofresponsesfalling
into each
of the
scoring categories.
Although there
is
considerable consistency over
the 9-
month retention interval, there is also substantial evidence of
forgetting
and inaccuracy.First,the data for"don'tremem-
ber responses clearly reveal forgetting over the retention
interval. On the
immediate questionnaire,
26 of the 27 re-
peated-testing subjects provided a substantive answer to all
fourcircumstances questions,
and the
remaining subject gave
asubstantive response
to
three
of the
fourquestions.
On the
9-month questionnaire, however,4 of the 27 subjects(15.4%)
gave
"don't
remember responses to a total of 6 questions
theyhad answered substantively on the immediate question-
naire.
Further evidence
of
forgetting
may be
found
by
comparing
the
frequency
ofmorespecificandmore general responses.If
the accessible
information
remains constant over time, there
should be no
systematic
difference
between
the
immediate
and9-month questionnaires in
specificity
of responses. That
is,
although
corresponding immediate
and
9-month responses
mayoccasionally varyinspecificitydue tovariationinsub-
jects' decisionsabout
how
much
of the
accessible information
to report, we would expect the number of responses that
became more specificat 9monthsto beapproximatelythe
same as the number that became more general. On the other
hand,if theamountofaccessible
information
decreased over
the interval between questionnaires, we might expect a sys-
tematic
shift
toward more general responses on the 9-month
questionnaire.This
is
just what
we
found. Whereas only
7
responses became more specific,
20
became more general
(p