THE INFLUENCE OF PRESENTATION MODALITY, CONSEQUENCIALITY, AND
COLLABORATION ON THE ABILITY TO JUDGE MEMORY VERACITY
A Thesis
Presented to the faculty of the Department of Psychology
California State University, Sacramento
Submitted in partial satisfaction of
the requirements for the degree of
MASTER OF ARTS
in
Psychology
by
Monique Alicia Mendonca
SUMMER
2013
© 2013
Monique Alicia Mendonca
ALL RIGHTS RESERVED
ii
THE INFLUENCE OF PRESENTATION MODALITY, CONSEQUENCIALITY, AND
COLLABORATION ON THE ABILITY TO JUDGE MEMORY VERACITY
A Thesis
by
Monique Alicia Mendonca
Approved by:
__________________________________, Committee Chair
Jianjian Qin, Ph.D.
__________________________________, Second Reader
Emily Wickelgren, Ph.D.
__________________________________, Third Reader
Lisa Bohon, Ph.D.
____________________________
Date
iii
Student: Monique Alicia Mendonca
I certify that this student has met the requirements for format contained in the University
format manual, and that this thesis is suitable for shelving in the Library and credit is to
be awarded for the thesis.
__________________________, Graduate Coordinator
Jianjian Qin, Ph.D.
Department of Psychology
iv
___________________
Date
Abstract
of
THE INFLUENCE OF PRESENTATION MODALITY, CONSEQUENCIALITY, AND
COLLABORATION ON THE ABILITY TO JUDGE MEMORY VERACITY
by
Monique Alicia Mendonca
In the present study, I examined the effects of presentation modality, consequentiality,
and collaboration on the veracity judgments of others’ memories for childhood events (N
= 143, 72% female, age M = 21.30, SD = 3.40). Accuracy of individually-made veracity
judgments was higher when participants read transcripts of the memory reports compared
to when they watched the videotaped reports. Consequentiality did not significantly affect
judgment accuracy; however, participants in the serious consequence conditions rated
nonverbal cues as more important for their judgment. Participants who were more
accurate in veracity judgments rated true memories higher on clarity, plausibility,
typicality, consistency, confidence, and distinctiveness compared to false memories;
whereas less accurate participants rated false memories higher on the same memory
characteristics. Group deliberation resulted in more accurate group judgment of false
memories and an increase in overall confidence of their judgments after deliberation.
_______________________, Committee Chair
Jianjian Qin, Ph.D.
_______________________
Date
v
ACKNOWLEDGEMENTS
Foremost, I wish to express my sincere gratitude to my advisor, Dr. Qin, for the
continuous support of my thesis research, for his patience, dedication, and immense
knowledge. His guidance helped me complete all the aspects of my thesis research and
final writing. I could not have asked for a better or more understanding advisor.
Additionally, I would like to thank my other committee members, Dr. Wickelgren and
Dr. Bohon, for their insightful comments and intriguing questions.
Finally, I would like to acknowledge my family (especially my grandma,
Geraldine Toland and my mom, Deborah Mendonca) and friends for their unconditional
love and support, which has been of the upmost importance during this stressful yet
worthwhile chapter of my life.
vi
TABLE OF CONTENTS
Page
Acknowledgements ..................................................................................................... vi
List of Tables .............................................................................................................. ix
Chapter
1. INTRODUCTION……………………………………………………………….. 1
The Source Monitoring Framework.................................................................. 3
Detecting Deception ......................................................................................... 8
Judging the Veracity of Memory Reports ....................................................... 19
Hypotheses ..................................................................................................... 23
2. METHODS ........................................................................................................... 25
Participants ...................................................................................................... 26
Materials ......................................................................................................... 26
Procedure ........................................................................................................ 28
3. RESULTS ............................................................................................................. 31
Data Coding .................................................................................................... 31
Preliminary Analyses ...................................................................................... 31
Individual Judgments ..................................................................................... 32
Factors Related to Veracity Judgment ........................................................... 36
Importance of Cues in Veracity Judgment ..................................................... 43
Group Judgments ........................................................................................... 48
vii
4. DISCUSSION ....................................................................................................... 54
Appendix A. Transcriptions ..................................................................................... 61
Appendix B. Participant Information Questionnaire ................................................ 65
Appendix C. Memory Judgment Questionnaire ...................................................... 67
Appendix D. Perceived Cue Importance Questionnaire .......................................... 69
Appendix E. Post Deliberation Questionnaire .......................................................... 71
Appendix F. Instructions for the Memory Judgment Task ....................................... 72
Appendix G. Instructions for Group Deliberation ................................................... 74
References ................................................................................................................... 76
viii
LIST OF TABLES
Tables
1.
Page
Effects of Gender, Ethnicity, and Primary Language on Veracity Judgment
Accuracy and Confidence ................................................................................. 33
2.
Effects of Presentation Modality and Consequentiality on Veracity Judgment
Accuracy and Confidence ................................................................................. 34
3.
The Effects of Presentation Modality and Consequentiality on True/False
Memory Accuracy and Confidence .................................................................. 35
4.
Effects of Presentation Modality and Consequentiality on True/False Memory
Characteristic Ratings ....................................................................................... 37
5.
Memory Characteristic Ratings for True/False Memory Reports by Participants
with Low and High Memory Judgment Accuracy ............................................ 42
6.
Correlations of the Difference Scores for Characteristics of Memory ............. 43
7.
Summary of Principle Component Analysis on Potential Predictors of Memory
Judgment ........................................................................................................... 45
8.
Effects of Presentation Modality and Consequentiality on Importance Ratings
of Memory Cues ............................................................................................... 46
9.
Correlations Between Accuracy and Confidence with Importance of Cues .... 47
10.
Ratings of Importance of Cues by Gender ........................................................ 48
ix
11.
The Effects of Presentation Modality, Consequentiality, Memory Type, and
Collaboration on Accuracy and Confidence of Memory Report Veracity
Judgments ......................................................................................................... 50
x
1
Chapter 1
INTRODUCTION
Eyewitness testimony is an important part of many legal trials. In such trials,
jurors are often faced with the difficult task of discerning true or accurate testimonies
from ones that are false or inaccurate in order to reach a fair verdict. A substantial
amount of research exists on how people judge the truthfulness or accuracy of eyewitness
testimony (e.g., Brewer, Potter, Fisher, Bond, & Luszcz, 1999; Lindsay, Wells, &
O’Connor, 1989; Wells & Olson, 2003). For example, researchers have found that
plausibility, typicality, clarity, distinctiveness, consistency, confidence, ambivalence,
ease of recall, amount of details, and amount of contextual information are among the
factors that people tend to utilize when making their true/false decisions (e.g., DePaulo,
Lindsay, Malone, Muhlenbruck, Charlton, & Cooper, 2003; Sporer, 2004; Qin, Olge, &
Goodman, 2008).
The present study focuses on false memory, which can be defined as false beliefs
about the past that are experienced as memories (Lampinen, Neuschatz, & Payne, 1997).
That is, people mistakenly remember an entire event that did not occur. In contrast to
memory errors, which refer to inaccuracies in memories for events that did occur, false
memory is probably less common. Nevertheless, it is of great concern in cases that
involve, for example, recovered memories of childhood abuse. During the mid-1990s, a
series of criminal and civil cases involving recovered memories flooded the media.
Adults claimed to have recovered repressed memories of childhood sexual abuse
2
(typically during therapy) (Loftus, 1993; Wakefield & Underwager, 1992). A highly
publicized case of false memory within the context of recovered memories of childhood
abuse is the Holly Ramona case. In 1992, Holly accused and sued her father for
childhood sexual abuse based on recovered memories she discovered during therapy
(Ramona v. Isabella, 1994). Holly’s therapist explained to her that 60 to 80 percent of
patients suffered from a form of abuse such as sexual abuse. Initially, Holly was unable
to recall any abuse, however within a few months she had "flashbacks" of childhood
abuse, and received a sodium amytal interview. After the interview, Holly was informed
by the psychiatrists who conducted the interview that she described sexual abuse during
the interview. Following her accusations, which were based on recovered memories,
Holly’s parents divorced, and her father lost his job. Holly’s father then sued Holly’s
therapist for implanting the memories (Ramona v. Ramona, 1994). Subsequently, a court
dismissed Holly’s claim that her father abused her because her memories were deemed
unreliable (Johnston, 1997). Additionally, Holly’s father was awarded a monetary
judgment as a result of his lawsuit against the therapist. Cases such as the Holly Ramona
case highlighted the importance of understanding false memory, as well as how people
make memory veracity judgments, that is, judge a memory to be either true or false. The
term “veracity judgments” in the present study refers to participants’ true/false decisions
regarding others’ childhood memories.
In addition to practical significance, understanding false memory and veracity
also have theoretical significance. The task of judging the veracity of true and false
memory reports can be considered within the Source Monitoring Framework (SMF,
3
Johnson, Hashtroudi, & Lindsay, 1993).
To lay the foundation for the present study, this paper will begin with a discussion
of the source/reality monitoring process in general, then move on to interpersonal reality
monitoring and how judging one’s own memories relates to judging others’ memories.
Next, a review of the characteristics and detection of true/false statements will be
discussed, followed by a review of the characteristics and veracity judgment of true/false
memories. Lastly, factors that have the potential to influence true/false memory veracity
judgments are discussed.
The Source Monitoring Framework
Source monitoring refers to the process by which people identify the sources of
their memories or other mental representations. According to the Source Monitoring
Framework (Johnson et al., 1993), people rely on heuristic and systematic processes
when determining the sources of their memories. Heuristic judgments are automatic, and
depend upon qualitative characteristics of the memory such as perceptual, spatial,
temporal, semantic, and affective details (Johnson et al., 1993). In contrast to heuristic
judgments, systematic judgments are deliberate and compare memories one already holds
with memories of the event in question in order to determine the source. For example,
systematic judgments evaluate aspects such as the plausibility of an event and therefore
one might base veracity judgments on the degree of inconsistency, or, one may choose
either a more liberal or more strict response criteria when making source monitoring
decisions. Most source monitoring decisions are probably made automatically and rather
quickly. However, systematic processes may play an important role when source
4
monitoring is difficult, when, for example, evaluation of the characteristics of the
memory turns out to be ambiguous.
Although the SMF was proposed to describe source attribution of ones’ own
memories, it is possible that similar processes are also at play when people judge the
source of other people’s memories (i.e., interpersonal source monitoring). Just as a
memory of one’s own is more likely to be judged as true when it has a lot of perceptual
details, one might also be more likely to judge a memory of someone else as true if it has
a lot of perceptual details. To the extent that the processes underlying source monitoring
and interpersonal source monitoring are similar, the SMF provides a useful theoretical
framework within which interpersonal source monitoring can be studied.
Reality Monitoring
The type of source monitoring that is of particular relevance to the present study
is reality monitoring, which focuses on differentiating between memory or mental
representation that originated from an external source (e.g., I did X, therefore the memory
was “perceived”) and that originated from an internal source (e.g., I thought about doing
X, therefore the memory was “imagined”). A false memory can occur as a result of
reality monitoring failure. For example, participants in Loftus and Pickrell’s (1995) “Lost
in a Shopping Mall” study were asked to recall themselves being lost in a shopping mall
when they were young (a fictitious event). Some of the participants later had a false
memory of being lost in a shopping mall because they mistakenly attributed the imagined
source, which resulted from repeated description-writing of the event over the course of
five days, as perceived.
5
Johnson and Raye (1981) proposed that the characteristics of a memory play a
crucial role in a person’s decision about whether a memory has an internal or external
source. They posited that on average, externally generated memories have more spatial,
temporal, sensory perceptual, and semantic details than internally generated memories,
whereas internally generated memories include more information about cognitive
operations and are thought to be more schematic than externally generated memories.
Thus, a “typical” memory that is rich in a variety of details would be more likely judged
as true. Reality monitoring is an important process especially in understanding false
memory because false memories can be created based on confusion as to the source of a
memory (Johnson & Raye, 1981). For example, an internally generated memory can be
confused with an externally generated memory due to similarities in memory
characteristics; an internally generated memory may contain sensory details (at a lesser
extent than a typical external memory, but to a greater extent than a typical internal
memory) e.g., as the result of repeated imagining as sometimes occurs in psychological
therapy and thus an incorrect source attribution would be made.
Deciding if others’ memories are true or false is a form of reality monitoring
known as interpersonal reality monitoring. Interpersonal reality monitoring can be
defined as how people determine if others’ memories were imagined (false) or perceived
(true) (Johnson, Bush, & Mitchell, 1998). According to Johnson et al. (1998), people
would rate others’ perceived (true) memories as containing more perceptual, contextual,
and emotional details compared to imagined (false) memories if people use similar
criteria for judging others’ memories as they do for judging their own memories.
6
Characteristics of Memory
Johnson, Foley, Suengas, and Raye (1988) had participants rate memory
characteristics associated with their own memories by filling out the memory
characteristics questionnaire that they developed. Participants rated perceived memories
higher in perceptual information, contextual information, and supporting memories
compared to memories that resulted from imagined events (Johnson et al., 1988).
Furthermore, when participants explained how they knew an event actually occurred they
referred to perceptual information, contextual information, and supporting memories.
Similarly, in a study that compared characteristics of true and false memories created
using the Deese-Roediger-McDermott paradigm, where the presentation of the word lists
was manipulated by having either one or two people read the word lists and the
associativity of the critical lure (a word not present in a list but highly associated with the
words present in a list) was also manipulated (thus, the probability of producing a false
memory) by presenting a certain critical lure such as the word “needle” either with words
from the same list as the critical lure such as “thread, pin, eye, sewing, sharp, point, prick,
thimble, haystack, and thorn” or with random words from different lists not associated
with the critical lure such as “sister, chilly, and climber.” Participants rated perceived
words as containing more auditory details (mode of delivery) than words that were
falsely remembered (Mather, Henkel, & Johnson, 1997). The memory characteristics
associated with judging one’s own false memories are similar to the characteristics
associated with judging other people’s false memories. For example, Loftus and Pickrell
(1995) planted false memories of being lost in a shopping mall in adult participants.
7
When judging their own memories, participants were more confident in their true
memories compared to their false memories. Also, participants rated their false memories
as less coherent than their true memories (Porter, Yuille, & Lehman, 1999).
A memory characteristic that has received a lot of attention in the literature is
confidence, because it is a possible predictor of accuracy. As previously mentioned, when
judging if one’s own memory was true or false, participants were more confident in their
true memories compared to their false memories (Loftus & Pickrell, 1995); this trend also
appears to carry over to judging others’ (children’s) memories. In a study conducted by
Block, Shestowsky, Segovia, Goodman, Schaaf, and Alexander (2012), adults judging
others’ memories were the most confident in their judgments when children expressed
true memories. Moreover, adults were more confident in their veracity judgments when
children accurately denied memories compared to when children produced false
memories (Block et al., 2012). Adults were also confident in their judgments when the
children correctly denied events that did not occur (Block et al., 2012). Surprisingly,
adults were “somewhat confident” when judging children’s false reports which is
contrary to results obtained by Leichtman and Ceci (1995). Thus, there is a parallel
between judging one’s own memory and judging others’ memories. Additionally,
because others’ true memories were rated with higher confidence there must be certain
characteristics that differentiate true from false memories. The role of various memory
characteristics in veracity judgments of others’ memories was examined in the present
study.
8
Detecting Deception
A large literature exists on how people detect false reports that were made
intentionally (i.e., lies). People utilize verbal cues (such as amount of details provided)
and nonverbal cues (such as body movements) when making their true/false judgments
(DePaulo et al., 2003; Vrij, Edward, Roberts, & Bull, 2000). Because the cues people rely
on during deception detection to make their judgments are also available when people
judge the veracity of others’ memory reports it is possible that participants will utilize
similar cues in both situations.
Indicators of Deception
Verbal indicators. True and false reports differ on a variety of measures such as
content of the message and the method of delivery during recall. Criteria-Based Content
Analysis (CBCA) has been used to analyze statements based on factors related to
veracity. Steller and Köhnken (1989) list 19 characteristics that can help one distinguish
true from false reports: (1) logical structure, (2) unstructured production, (3) quantity of
details, (4) contextual embedding, (5) descriptions of interactions, (6) reproduction of
conversation, (7) unexpected complications during the incident, (8) unusual details, (9)
superfluous details, (10) accurately reported details misunderstood, (11) related external
associations, (12) accounts of subjective mental state, (13) attribution of perpetrator’s
mental state, (14) spontaneous corrections, (15) admitting lack of memory, (16) raising
doubts about one’s own testimony, (17) self-deprecation, (18) pardoning the perpetrator,
and (19) details characteristic of the offense. Out of the 19 CBCA characteristics,
quantity of details has received the most support, meaning true reports consisted of more
9
details than false reports (Vrij, 2005). Also, true reports consisted of more perceptual
details (vision and sound), more information about locations, more information about
time, and mentioned more cognitive operations than false reports (Vrij et al., 2000).
Unstructured production (information is not given in chronological order), contextual
embedding (information is given in the context of time and space), and reproduction of
conversation (dialogue in its original form) were also found more often in true reports
(Vrij, 2005). Overall, 92% of the time true reports received a higher total CBCA score
than false reports (Vrij, 2005).
In addition to the CBCA criteria, people providing true reports responded to
questions quicker, the true reports tended to be longer, and contained less speech
disturbances (i.e. ah’s, um’s, and er’s) (DePaulo, Rosenthal, Rosenkrantz, & Green,
1982; Vrij et al., 2000). False reports tended to contain more negative words and less
first-person pronouns which is thought to occur due to feelings of guilt and to avoid
accepting responsibility, respectively (Pennebaker, Francis, & Booth, 2001).
The predictive value of the aforementioned characteristics to deception detection
can be altered if there is adequate time to prepare false reports. For example, when people
have time to prepare their false reports before an interview the responses contain
characteristics similar to true reports compared to unprepared people. Prepared people
providing false reports are quick to respond to questions similar to people providing true
reports; however, prepared people delivering false reports also repeated words, phrases,
and details more frequently than those providing true reports (DePaulo et al. 2003; Porter,
Yuille, & Lehman, 1999; Sporer & Schwandt, 2006).
10
The research on verbal indicators of deception shows that some of the differences
between true and false reports are similar to what the SMF predicted such as the presence
of more perceptual details. Thus, to the extent that similar differences exist between true
and false memories, these research can provide clues to what cues people may use to
detect false memories. For example, true memories may contain more details than false
memories, thus, the amount of details could potentially be used as a clue for judging the
veracity of memory reports. However, to what extent people actually use this criterion in
their veracity judgments has not yet been studied. The present study examined the
importance participants placed on such characteristics when making their veracity
judgments.
Nonverbal indicators. Ekman (1992) proposed that feelings of fear, excitement,
and guilt lead to behaviors indicative of deception. Research has found that there is a
difference in the nonverbal behavior displayed by people providing true versus false
reports. In terms of facial movements, against popular belief, decreases in both eye gaze
aversions and blinking are indicative of deception (Vrij & Mann, 2001; Vrij & Semin,
1996). In addition, higher-pitched voices, slower rates of speech, longer pauses, shorter
responses, and longer latency periods have also been shown to be clues to deception (Vrij
& Mann, 2001; Vrij & Semin, 1996). Interestingly, smiles, head movements, trunk
movements, and fidgeting have been shown to be unrelated to deception (DePaulo et al.,
2003; Vrij & Semin, 1996).
In regards to body movement, decreases in behaviors such as self-touch,
illustrations (controllable hand and arm movements), hand and finger movements,
11
shiftiness, and trunk movements have been shown to be valid predictors of deception
(DePaulo et al., 2003; Vrij et al., 2000; Vrij & Semin, 1996). DePaulo et al. (2003)
postulated that the purpose of the decrease in movements that liars display when
reporting an event, is to appear calm; and therefore similar to a truth teller.
Factors that Affect the Accuracy of Detecting Deception
Given that people often have to judge the truthfulness of others in daily life,
where the consequences of inaccuracy vary in severity, one would assume people to be
skillful judges; however, this is not always the case. Bond and DePaulo’s (2006) metaanalysis revealed that people’s deception detection accuracy is only slightly above
chance—54%. Interestingly, accuracy also varied depending on the type of report being
judged—true or false; people were better at detecting truths (67%) than lies (44%) (Vrij,
2000). This “veracity effect” or “true-bias” is believed to occur due to people’s tendency
to judge messages as truthful (Levine, Park, & McCornack, 1999).
Deception detection expertise. With overall deception detection accuracy
hovering around chance, perhaps certain groups of individuals outperform others. One
class of individuals outperformed the rest: secret service agents (Ekman & O’Sullivan,
1991). Secret service agents were better at deception detection (Accuracy M = 64.12, SD
= 14.80) compared to college students (Accuracy M = 52.82, SD = 17.31); this result is
possibly due to the similarity in the deception detection format of the study and the
format utilized in their jobs (Ekman & O’Sullivan, 1991). For example, secret service
agents typically detect deception in an interview format and Ekman and O’Sullivan
(1991) had participants judge videotapes of participants answering an interviewer’s
12
questions—highly similar format. On the other hand, Akehurst, Köhnken, Vrij, and Bull
(1996) found that police officers who detect deception as part of their jobs held as many
false beliefs about deception detection as lay persons (community members, not just
college students), and did not achieve higher accuracy scores than lay persons (Bond &
DePaulo, 2006). Thus, secret service agents’ specialized training or job experiences may
set them apart from police officers as well lay persons in their deception detection ability.
When asked to rate the relation of verbal and nonverbal cues with deception detection
accuracy, police officers, judges, and prosecutors all indicated that verbal and nonverbal
cues were equally reliable in deception detection; moreover, judges and prosecutors
placed more weight on verbal cues than nonverbal cues during their ratings whereas
police officers held the opposite belief (Strömwall & Granhag, 2003). The placement of
more weight on nonverbal cues and thus on the difference in nonverbal behaviors
displayed in true and false reports highlights the notion that certain behavioral cues exist
that can be utilized to detect lies, however, certain cues are more informative than others.
However, Zuckerman, DePaulo, and Rosenthal’s (1981) multi-factor model argues that
there is not a single factor that distinguishes someone telling the truth from someone
telling a lie; the researchers posit that multiple factors influence cues to deception. For
example, under the emotional arousal perspective, lies are associated with the emotions
of fear, guilt, and excitement; thus, behaviors associated with such emotions will possibly
be evoked during deception such as eye gaze aversion, increases in eye blinks, self touch,
speech hesitations, speech errors, and higher pitch (Ekman, 1992). Interestingly, the
behavior displayed depends on the specific emotion the truth teller or liar is experiencing:
13
someone experiencing negative emotions may display less movements whereas someone
experiencing excitement may display more movements (Vrij, 2008; Zuckerman,
DePaulo, & Rosenthal, 1981). Therefore, behavioral cues, such as movements, are
indicative of deception; however, such behavioral cues are also influenced by other
factors.
Deception detection experts as well as lay persons’ inabilities to judge
truthfulness of reports may be due to the format of the task. Vrij, Edward, and Bull
(2001) discovered that police officers were able to detect false reports indirectly (i.e.
when asked, “does the person have to think hard?”) but not directly (i.e. when asked, “is
the person lying?”). This result may due to the cognitive load of the people reporting the
true and false reports. Cognitive load is thought to be a reason why there is a difference in
the behaviors of people providing true and false reports (Vrij, 2008; Zuckerman et al.,
1981). In Vrij et al.’s (2001) study, nursing students had very little time to come up with
false reports thus creating a higher cognitive load. The evidence of a higher cognitive
load on the part of the nursing students providing false reports is clear because
differences in displayed behaviors arose between themselves and those providing true
reports. Nursing students providing false reports had longer latency periods, more speech
hesitations, less hand/finger movements, less illustrators, and lower total CBCA scores
than truth tellers (Vrij, Edward, & Bull, 2001). Thus, the researchers hypothesized that
police officers would be able to distinguish people providing false reports from people
reporting true reports on the basis of the indicators of cognitive load (longer latency
period and decrease in movement). The indirect question method allowed police officers
14
to solely focus on actual indicators of deception (such as cognitive load cues) which
resulted in a higher deception detection accuracy compared to the direct question method
which led officers to include invalid cues in addition to valid cues in their judgments
(Vrij et al., 2001).
Thus, people, including police officers, judges, prosecutors, prisoners, college
students, and community members, tend to only have slightly above chance deception
detection accuracy. However, there are ways to increase deception detection accuracy
such as focusing on verbal cues as well as the select nonverbal cues indicative of
cognitive load. For example, people’s deception detection ability may be influenced by
manipulations that vary the degree of cue availability (verbal and nonverbal). If deception
detection accuracy can be influenced by cue availability, then it is possible that false
memory detection ability might also be affected by cue availability.
Presentation modality. As previously discussed, the availability of nonverbal
cues may adversely affect the accuracy of deception detection and veracity judgment.
Manipulating presentation modality of the true and false reports can alter cue availability
and thus, potentially, accuracy. Davis, Markus, and Walters (2006) manipulated the
characteristics of interviews participants were able to use when making their deception
decisions by showing participants a complete video (visual and audio), only audio, or a
verbatim transcript (no visual or audio). An interesting trend appeared as the result of this
manipulation: participants in the audio only condition were more accurate than the
participants in the video and verbatim transcript conditions at discerning true from false
reports. Although the trend only approached statistical significance, the finding was
15
interesting because it suggests that being able to see the interviewee might negatively
influence true/false decision accuracy. The researchers believed that the lack of
significance was due to a small sample size (Davis, Markus, & Walters, 2006). Similarly,
Burgoon, Blair, and Strom (2008) found that people rating false reports have a
disadvantage when they have access to visual nonverbal cues (such as viewing a video)
resulting in decreased deception detection accuracy. On the other hand, raters have an
advantage when they only have access to verbal cues (such as reading a transcript)
(Burgoon, Blair, & Strom, 2008). Thus, accuracy degrades with the addition of visual
nonverbal cues during deception detection.
Consequentiality. We make low stakes veracity judgments daily such as when
we have conversations with friends. We also make high stakes judgments, such as
deciding whether a defendant is guilty or not guilty during jury duty, much less
frequently. The consequences of inaccuracy, however, are vast for high stakes judgments.
Bond and DePaulo (2006) noted in their meta-analytic review that only 12% of
participants who judged reports had any special incentive to successfully distinguish true
from false reports. From the SMF perspective, one of the ways consequentiality can
influence the deception detection process is through the use of systematic judgment. For
example, systematic judgments evaluate aspects of an event such as plausibility;
therefore, one might base veracity judgments on the degree of plausibility of an event, or,
in other words, one may choose either a more liberal or more strict response criteria when
making source monitoring decisions (Johnson et al., 1993). A strict criteria when making
source monitoring decisions would mean a person requires a higher degree of plausibility
16
to say a memory was perceived (i.e., true) rather than imagined (i.e., false); therefore, the
use of strict criteria should increase accuracy rates.
Collaboration. In addition to the characteristics of true and false reports,
presentation modality, and consequentiality, group collaboration also influences
participants’ deception detection accuracy. Collaboration has practical importance
because in legal cases jurors try to reach a consensus through deliberation.
Studies on group collaboration and deception detection have consistently reached
the same conclusion: groups experience collaboration inhibition (Harris, Paterson, &
Kemp, 2008). Collaboration inhibition is the term for the diminished accuracy level of
participants when making deception judgments in a group compared to when alone. For
example, collaboration inhibition occurred when Israeli students were asked about the
assassination of Prime Minister Rabin (Yaron-Antar & Nachson, 2006). Similarly, Harris,
Barnier, and Sutton’s (2012) results were consistent with previous research; however, the
results were only in line with previous research when groups were described as turntaking. In their study, participants learned a list of words individually and recalled the
words either individually (3 individuals’ responses analyzed together to simulate a turntaking group), in a three-member group that took turns recalling, or in a three-member
group that reached a consensus. Interestingly, when groups reached a consensus they
were more accurate compared to the turn-taking groups (Harris, Barnier, & Sutton, 2012).
The researchers attributed this effect to the benefits of group source monitoring called
“group error checking” where errors in recall were removed during the deliberation
process, thus, increasing group accuracy.
17
Criteria Used for Deception Detection
Hartwig and Bond’s (2011) meta-analysis examined the notion that people tend to
rely on stereotypical (and inaccurate) cues to deception such as gaze aversion and
increases in body movements. The wrong subjective cue hypothesis (people have an
inaccurate view of the characteristics of deceptive behavior and thus base their judgments
on such invalid cues) and the weak objective cue hypothesis (judgments are inaccurate
due to a lack of valid cues for them to base their judgments on) were of interest in the
meta-analysis (Hartwig & Bond, 2011; Vrij, 2008). Previous researchers have noted that
when people judge the truthfulness of reports they base their judgments on their own
knowledge, that is, people compare the to-be-judged report with their own understanding
of a situation (Vrij, 2004).
Regardless of people’s general inability to predict the extent of the relation
between the cue and deception there are some cues that people judge appropriately. In
general, people think deceptive reports are comprised of fewer details, are less consistent,
less plausible, less realistic, and not spontaneous compared to truthful reports, and this
view is supported by research (Hartwig & Bond, 2011; Strömwall & Granhag, 2003).
When judging deceptive statements, those who appear incompetent and fail to mention
the context of the event in question are often correctly judged as being deceitful (Hartwig
& Bond, 2011).
Despite the fact that people can utilize certain memory cues to detect deception
there are situations in which people misjudge the relations between cues and deception.
In terms of verbal cues, research has shown that people engaging in deception tend to
18
have higher pitched voices compared to truth tellers; however, people generally believe
there is not a relation between pitch and veracity or they admit to being unsure about that
cue (Strömwall & Granhag, 2003). People also tend to misattribute cues related to the
delivery method of reports. Akehurst, Köhnken, Vrij, and Bull (1996) found a tendency
for people to believe that hectic speech is expected to increase when it actually decreases
during deception. False starts and faltering speech are believed to decrease when they
actually increase during deception (Akehurst, Köhnken, Vrij, & Bull, 1996).
In addition to the aforementioned misconstrued cues to deception, people also
confuse the relation of some nonverbal cues and deception. For example, when people
are unfamiliar with the content of the statement and are thus unable to cross-check the
content of the statement with their own knowledge they tend to rely on nonverbal cues
(Vrij, 2004). Reliance solely on nonverbal cues has its flaws. For example, people’s own
beliefs about the nature of lie detection and deceptive cues have often been shown to be
inaccurate. According to research, people believe an increase in certain physical
behaviors can serve as a clue to deception; however, people tend to focus on
characteristics that are not indicative of deception (Strömwall & Granhag, 2003; Vrij &
Semin, 1996). People (lie detection experts, college students, and lay persons)
consistently list increases in movements such as eye gaze aversion, shiftiness/fidgeting,
self-touch, and body (head, arm, hand, finger, foot, leg, and truck) movements as clues
they use when deciphering true from false reports (Akehurst et al., 1996; Hartwig &
Bond, 2011; Vrij, 2004; Vrij & Semin, 1996). Nonetheless, against popular belief, it is a
decrease in movement and behaviors such as eye gaze aversions, self-touch, shiftiness,
19
and trunk movements that have been shown to be valid predictors of deception (Vrij &
Semin, 1996). Not surprisingly, people also believe it is easier to detect deception during
face-to-face interrogations compared to watching the same interrogation on video, when
in fact the opposite is true (Strömwall, 2003).
Many factors influence one’s deception detection ability. Vrij (2000) noted that
people who utilize verbal cues are more accurate than people who utilize nonverbal cues.
However, revealed by Hartwig and Bond’s (2011) meta-analysis, reliance on global
impressions is a better strategy for deception detection. Global impressions are thought to
consist of minute verbal and nonverbal behavioral changes (Hartwig & Bond, 2011).
Hartwig and Bond (2011) discovered that people’s cue reliance seems to be in
line with deceptive behaviors (verbal and nonverbal), and that people tend to rely on cues
that are actually related to veracity. However, Hartwig and Bond (2011) also found a
tendency for people to overestimate both nonverbal and verbal cues’ relation with
deception, which reflects stereotypical views of deceptive behaviors. Thus, people’s
views of deceptive behaviors are less flawed than previously thought, but are still far
from accurate (Hartwig & Bond, 2011).
Judging the Veracity of Memory Reports
The ability to judge the veracity of other people’s memory reports has both
important theoretical and applied implications. A substantial amount of research exists on
factors related to deception detection; however, there is relatively less research on
veracity judgments of memory reports. Deception and false memories are similar in that
the event in question did not happen; however, the difference lies in intentionality, with
20
deception, people were intentionally lying, but with false memory, people were genuinely
remembering something that did not happen. The research on deception detection is
helpful for understanding veracity judgments of memory reports because the tasks are
similar (recall of event) and verbal and nonverbal cues are both present.
Indicators of False Memory
Verbal indicators. In Qin et al.’s (2008) study, participants were asked to recall
childhood memories that happened to them before the age of five years (Experiment 1).
The researchers had the participants recall 1-4 true events and one false event. The false
events recalled, and thus the false memories created, were either a Birthday Party at
McDonald’s or Going to a Hospital for an Injury. In their Experiment 3, a different group
of participants judged the veracity of the memory reports from Experiment 1, rated the
characteristics of the memory reports, and answered questions about the importance of
certain cues in their veracity judgments. Their results showed that true memories were
rated higher on several memory characteristics (clarity, plausibility, typicality,
consistency, distinctiveness, perceived ease of recall, and perceived confidence)
compared to false memories.
Other research showed that compared to true memories, false memories made less
sense, were more discrepant and ambivalent, contained less relevant details, less
contextual information, contained fewer units of information in regards to emotion and
action detail (DePaulo et al., 2003; Pezdek & Taylor, 2000; Qin et al., 2008; Sporer,
2004).
In addition to the characteristics of memories of events, Mather, Henkel, and
21
Johnson (1997) examined the characteristics of memories following a DRM task.
Participants rated false memories for the critical lures as containing less auditory details
and remembered less feelings and reactions compared to participants’ correct rejections.
Nonverbal indicators. When judging the veracity of memory reports, the
delivery method of the report itself has not received attention in the literature. Qin et al.
(2008) had participants rate the importance of facial expressions, vocal intonation, and
body language, as well as other verbal characteristics, to participants’ veracity judgments.
The nonverbal cues were combined into a factor deemed “Expression” based on a
principal components analysis. The nonverbal component, Expression, was rated as less
important than confidence, ease of recall, consistency, and clarity.
Accuracy and Confidence of Veracity Judgment
In Qin et. al’s (2008) study, participants watched 20 videotaped memory reports
(10 true and 10 false) of childhood events and subsequently made veracity judgments.
Qin et al. (2008) observed a hit rate of 64.1% for true memories as well as a 41.1% false
alarm rate for false memories. Additionally, participants were more confident in their
veracity judgments when they judged a true memory correctly compared to when they
made an error.
Factors that Affect the Accuracy of Veracity Judgment
Presentation modality. As previously mentioned, the verbal and nonverbal cues
people focus on during deception detection influences accuracy rates. Thus, manipulating
presentation of true and false memory reports will alter cue availability and, thus
potentially, veracity judgment accuracy. Research by Davis et al. (2006) suggests that
22
being able to see the interviewee might influence true/false decisions in deception
detection; therefore, in the present study participants either saw the people describing
memories of childhood events or read a transcript of the memory reports. Similarly,
Burgoon et al. (2008) found, in terms of deception detection, that access to visual
nonverbal cues (such as viewing a video) was detrimental to accuracy whereas access to
verbal cues was advantageous. Given these results, in the present study the availability of
nonverbal cues was manipulated by varying the presentation modality of memory reports;
nonverbal cues such as facial expression, vocal intonation, and body movement were
either available (when the memory reports were presented in videos) or not available
(when the memory reports were presents in transcripts). The possible effect of this
manipulation on the accuracy and confidence of veracity judgments was then examined.
Consequentiality. The consequences of inaccuracy when judging true and false
memory reports are vast. In regards to deception detection, only 12% of participants had
any special incentive to successfully distinguish true from false reports (Bond &
DePaulo, 2006). Typically when incentives are present they are monetary, but what are
the effects of a non-monetary incentive? A nonmonetary incentive that has the possibility
of influencing accuracy rates of memory veracity judgments is a consequence. In the
present study, the presumed seriousness of the context in which participants made their
veracity judgments was manipulated to examine the possible effect of consequentiality.
Collaboration. In civil and criminal legal cases, the ultimate veracity judgment is
made by a group of jurors after deliberation. Harris et al. (2012) found that groups were
the most accurate at determining true from false reports when they reached a consensus.
23
In terms of memory veracity judgments, the enhanced accuracy rate that accompanies
group collaboration also occurs for people’s own recognition memories. Clark, Hori,
Putnam, and Martin (2000) demonstrated that after group collaboration participants
recognized more previously seen words compared to when they made the judgments on
their own. Interestingly, the effect of collaboration was not present for rejecting
distractors (Clark, Hori, Putnam, & Martin, 2000). Thus, group collaboration aids in the
recognition of true memories but not false memories. To the extent that judging one’s
own memory is similar to judging others’ memories it is important to understand the
possible effects of such group collaboration on the accuracy and confidence of judging
others’ true and false memories.
Hypotheses
Presentation Modality
In the present study, a cue availability manipulation was embedded in the
presentation of the memory reports; participants who judged the videotaped memory
reports had access to every available cue, whereas participants who judged the
transcriptions of the memory reports did not have access to nonverbal cues. Thus,
participants who watched the videotaped memory reports were hypothesized to be less
accurate in their veracity judgments than participants that read the transcriptions of the
memory reports (Burgoon et al., 2008; Davis et al., 2006).
Consequentiality
Participants who were given a serious consequence were hypothesized to be more
accurate in their veracity judgments over those given a benign consequence because the
24
serious consequence condition was expected to prompt participants to use more
conservative criteria (that is, be more reluctant to label a memory as true) and thus be
more accurate in their veracity judgments compared to participants with a benign
consequence and presumably with a more liberal criteria (Johnson et al., 1993).
Collaboration
Reaching a consensus is associated with higher accuracy; thus, I hypothesized that
during group discussion errors in individual judgments would be removed due to “group
error checking” thus making the group judgments more accurate than individual
judgments (Clark et al., 2000; Harris et al., 2012).
25
Chapter 2
METHODS
The purpose of the present study was to examine the effects of presentation
modality, consequentiality, and collaboration on participants’ ability to judge the veracity
of others’ memories for childhood events. I also aimed to explore the type of cues used in
making true/false judgments. Participants either watched the video recording (video
condition) or read the verbatim transcripts (transcript condition) of true and false memory
reports of childhood events. They were either asked to act as if they were in friendly
competition (benign consequence condition) to see who was the best at judging the
veracity of memories or that they were to act as if they were members of a legal
investigation team (serious consequence condition) and their task was to figure out if the
remembered events actually occurred or not because a serious crime was suspected to
have occurred during the event. First, participants made the veracity judgment on their
own then they completed a set of questionnaires about the characteristics of memory
reports and the importance of verbal and nonverbal cues in their veracity judgment. For
individual judgments, the design was a 2 (presentation modality: video vs. transcript) x 2
(consequentiality: serious vs. benign) between-subjects design. Finally, participants
worked together as a group to judge the veracity of the memory reports with the goal of
coming to a consensus on the veracity judgment (i.e., a “verdict”). For group level
judgments, the design was a 2 (presentation modality: video vs. transcript) x 2
(consequentiality: serious vs. benign) x 2 (deliberation: pre vs. post) mixed factorial
26
design, with deliberation being the within-subjects factor. The pre-deliberation judgment
was calculated as the mean of the (pre-deliberation) individual judgments within the
group.
Participants
One hundred forty eight undergraduate students from California State University,
Sacramento participated in the study. In exchange for their participation they received
research credit or extra credit for a particular course. Data from five participants were
removed from the analyses due to an experimenter errors. Thus, data from 143
participants were used in the final analyses (females, n = 103, males n = 40). Their age
ranged from 18 to 39 years old (M = 21.30, SD = 3.40). The ethnic background of the
sample was: European American (n = 38; 26.6 %), Asian American or Pacific Islander (n
= 38; 26.6 %), and Hispanic, Latino, or Spanish (n = 32; 22.4 %). The remaining
participants were Multi-Ethnic (n = 17; 11.9 %), African American (n = 8; 5.6 %),
Middle Eastern (n = 4; 2.8 %), American Indian, Eskimo, or Aleut, (n = 1; 0.7 %), other
(n = 4; 2.8 %), or declined to state (n = 1; 0.7 %).
Materials
Videos and Transcripts of Memory Reports
Videotaped and transcribed true and false memory reports of childhood events
(Birthday Party at McDonald’s, or Going to a Hospital for an Injury) were used in the
present study. The memory reports were obtained from Qin et al.’s (2008) study where
participants were asked to recall childhood memories that happened to them before the
age of five years. Participants were informed that their parents provided information
27
regarding several childhood events that they experienced and that their task was to recall
each event in detail. Participants were also told to report their own memories for the
events as opposed to memories from others or memories as a result of a picture. In that
study, the researchers had the participants recall 1-4 true events and (unknown to these
participants) one false event. Four memory reports (one true and one false for each of the
two events) were selected randomly, with the constrain that the memory reports were
approximately of equal length (see Appendix A). The original participants in Qin et al.’s
(2008) study provided permission that the videotaped and transcribed memory reports
could be used in future studies.
Participant Information Questionnaire
The participant information questionnaire contained five questions related to
demographic variables such as age, gender, ethnicity, and primary language. In addition
to the demographic questions, participants also rated their own ability to decipher true
from false memories on a scale ranging from 1 = very unconfident to 6 = very confident
(Appendix B).
Memory Judgment Questionnaire
The Memory Judgment Questionnaire was obtained from Qin et al.’s (2008) study
and contained 10-items. For each of the four memory reports, participants indicated if the
memory in question was true or false, and also indicated their confidence in their veracity
judgment on a 6-point scale (1 = very unconfident to 6 = very confident). The
questionnaire was modified to enable participants to describe up to three reasons for their
veracity judgment. Participants also rated the memory on clarity, plausibility, typicality,
28
consistency, confidence, distinctiveness, and ease of recall on the same 6-point scale,
with 1 = very unclear, 6 = very clear, etc. (Appendix C).
Perceived Cue Importance Questionnaire
The Perceived Cue Importance Questionnaire was obtained from Qin et al.’s
(2008) study and contained 12 items. Participants rated how the importance of clarity,
plausibility, typicality, consistency, confidence, facial expression, vocal intonation, nonfacial body language, amount of information, distinctiveness, and ease of memory
retrieval influenced their true/false judgments on a scale ranging from 1 = very
unimportant to 6 = very important. Additionally, participants were able to include their
own characteristic that they thought influenced their veracity judgment and confidence
rating. The questionnaire was modified in regards to the instructions for evaluating the
importance of nonverbal characteristics (facial expression, vocal intonation, and nonfacial body language), with the participants who did not have access to such
characteristics (transcript condition) instructed to rate the characteristics according to
how each of them would have been important to their true/false judgments (Appendix D).
Post Deliberation Questionnaire
Following group deliberation, participants noted their group’s memory veracity
judgment, their individual confidence level in their group’s veracity judgment, and listed
3 reasons/clues for making the true/false memory judgment (Appendix E).
Procedure
The experiment was conducted in small groups of 3-6 participants with an
average group size of 4.61 (SD = .99). Each group of participants was randomly assigned
29
to either the video or transcript conditions.
Prior to watching the first video or reading the first transcript, participants were
informed that they were to act as if they were in friendly competition to see who was the
best at judging the veracity of memories (the benign consequence condition) or that they
were to act as if they were members of a legal investigation team and their task was to
figure out if the remembered events actually occurred or not because a serious crime was
suspected to have occurred during the event (the serious consequence condition)
(Appendix F).
If participants watched the videotaped memory reports (the video presentation
condition), the experimenter showed one of four memory reports (two Birthday Party at
McDonald’s memory reports and two Going to a Hospital for an Injury memory reports)
once on a laptop to the entire group. For the transcribed memory reports, participants read
the transcript once and then they were not allowed to flip back to the transcript once they
began filling out the memory judgment questionnaire (the transcript presentation
condition).
After watching/reading each of the four memory reports, participants first
provided their own assessment of the veracity of the memory reports by filling out the
Memory Judgment Questionnaire for each memory report. Next, participants completed
the Perceived Cue Importance Questionnaire where they rated the importance of
perceived clarity, plausibility, typicality, consistency, confidence, facial expression, vocal
intonation, non-facial body language, amount of information, distinctiveness, and ease of
memory retrieval of the memories.
30
Next, participants were informed that they would be working together as a group
to judge the veracity of the memory reports with the goal of coming to a consensus on the
veracity judgment (Appendix G). At the beginning of the group deliberation, the
members of the group selected a foreperson who was responsible for directing the
discussion. After the foreperson was selected, participants either watched each video or
read each memory report again, depending on the presentation modality conditions they
were in. Following each report, the foreperson took the initial vote, that is, each group
member stated their judgment for the memory report beginning with the foreperson. Then
the foreperson lead the group discussion where the group discussed their reasons for their
judgments and tried to reach a group consensus. The participants had a maximum of five
minutes for each memory report as timed by the experimenter. When they finished the
discussion (or reached the 5 minute limit), the foreperson was responsible for taking the
final vote and everyone recorded the final vote on the Post Deliberation Questionnaire.
All group deliberations were videotaped to facilitate the future analysis of the
deliberation process.
31
Chapter 3
RESULTS1
Data Coding
Participants’ veracity judgments were coded as 1 = correct and 0 = incorrect. An
overall veracity judgment accuracy score was created for each participant by averaging
the accuracy scores across the four memory reports. In addition, separate accuracy scores
were created for the true and false events by averaging the accuracy scores across the two
true events and two false events, respectively.
Likewise, in order to achieve an overall confidence in veracity judgment measure
an average score was created for each participant by averaging self-reported scores across
the 4 judgments based on the scale provided (1 – very unconfident to 6 – very confident).
The true confidence and false confidence in veracity judgment scores were created by
averaging participants’ scores on the two true events and two false events separately.
Preliminary Analyses
To assess whether ethnicity (European American vs. non-European American),
primary language (English vs. non-English), and gender (male vs. female) were related to
the accuracy and confidence of the veracity judgments, a series of one-way analyses of
variance (ANOVAs) were conducted with individual accuracy score as the dependent
variable. The results revealed that only gender was significantly related to the overall
1
Open-ended responses (e.g., three reasons participants listed as to why they made
their particular veracity judgments & group deliberation) will be analyzed later.
32
judgment accuracy, females were more accurate, F(1, 141) = 6.05, p < .05, ηp2= .04 (see
Table 1). Correlations between veracity judgment accuracy, age, and confidence in ability
to detect false memory were calculated. There were no significant correlations between
veracity judgment accuracy and age, r = .03, p > .05, or self-reported confidence in
ability to detect false memory, r = .05, p > .05. To assess whether ethnicity, primary
language, and gender were related to confidence in the veracity judgments, a series of
one-way ANOVAs were conducted with individual confidence ratings as the dependent
variable. The results revealed that none of the variables were significantly related to
judgment confidence, Fs < 1.38, ps > .05. There was no significant correlation between
veracity judgment confidence and age, r = .08, p > .05; however, self-reported confidence
in ability to detect false memory was positively correlated with judgment confidence, r =
.28, p < .01.
Individual Judgments
Accuracy of the Veracity Judgment
I predicted that participants who read the transcripts of the memory reports and
with a serious consequence attached to their veracity judgments would be the most
accurate. To test this hypothesis, a 2 (presentation modality: video vs. transcript) x 2
(consequentiality: serious vs. benign) between-subjects ANOVA was conducted to assess
the effects of presentation modality and consequentiality on veracity judgment accuracy
with individual veracity judgment accuracy as the dependent variable. The analysis
revealed a significant main effect of presentation modality on accuracy, with participants
33
Table 1
Effects of Gender, Ethnicity, and Primary Language on Veracity Judgment Accuracy and Confidence
Gender
Ethnicity
Male
Female
(n = 40)
(n = 103)
European
American
(n = 38)
Primary Language
non-
European
English
non-English
Total
American
(n = 113)
(n = 30)
(N= 143)
(n = 104)
Accuracy
.44 (.29)
.59 (.31)
.60 (.31)
.52 (.31)
.55 (.32)
.53 (.28)
.55 (.31)
Confidence
4.29 (.49)
4.17 (.57)
4.19 (.46)
4.21 (.58)
4.19 (.51)
4.23 (.68)
4.20 (.55)
34
who read the transcripts of the memory reports achieving higher accuracy compared to
participants who watched the videos, F(1, 139) = 3.96, p < .05, ηp2 = .03. The main effect
of consequentiality was not significant, F(1, 139) = .28, p > .05. In addition, the
interaction between presentation modality and consequentiality was not significant, F(1,
139) = .001, p > .05 (see Table 2).
Table 2
Effects of Presentation Modality and Consequentiality on Veracity Judgment Accuracy
and Confidence
Presentation Modality
Consequentiality
Video
Transcript
Benign
Serious
Total
(n= 71)
(n = 72)
(n = 66)
(n = 77)
(N =143)
Accuracy
.49 (.34)
.60 (.28)
.53 (.29)
.56 (.34)
.55 (.31)
Confidence
4.22 (.53)
4.18 (.56)
4.21 (.59)
4.19 (.51)
4.20 (.55)
Delving deeper into participants’ veracity judgment accuracy, the accuracy for
true and false events were analyzed further in a 2 (memory type: true vs. false) x 2
(presentation modality: video vs. transcript) x 2 (consequentiality: serious vs. benign)
mixed ANOVA with memory type varying within-subjects. The main effect of memory
type was not significant, F(1, 139) = .26, p > .05. However, there was a significant
memory type by presentation modality interaction, F(1, 139) = 4.10, p < .05, ηp2 = .03.
Simple effect analysis revealed that for the false events, participants that read the
transcripts were more accurate in their veracity judgments compared to participants that
watched the videos, F(1, 141) = 8.44, p < .01. For the true events, participants who read
the transcripts were no more accurate than participants who watched the videos, F(1,
35
141) = .17, p > .05. Simple effect analyses also indicated that participants in the video
condition judged true memories more accurately than the false memories, F(1, 70) =
4.93, p < .05, ηp2 = .07. There was no significant difference in judging true and false
memories for participants in the transcript conditions, F(1, 70) < 1, p > .05.Thus, it
appears that the difference in the overall judgment accuracy between the video and
transcript conditions was driven by the difference in the accuracy of judging the false
events. No other significant main effects nor interaction were found, Fs(1, 141) < 1, ps >
.05 (see Table 3).
Table 3
The Effects of Presentation Modality and Consequentiality on True/False Memory
Accuracy and Confidence
Presentation Modality
Consequentiality
Video
Transcript
Benign
Serious
Total
(n = 71)
(n = 72)
(n = 66)
(n = 77)
(N = 143)
True
.54 (.38)
.57 (.41)
.52 (.36)
.58 (.42)
.56 (.39)
False
.44 (.39)
.63 (.35)
.54 (.35)
.53 (.41)
.54 (.38)
True
4.17 (.74)
4.22 (.72)
4.17 (.77)
4.22 (.69)
4.20 (.73)
False
4.26 (.62)
4.15 (.59)
4.25 (.68)
4.16 (.54)
4.20 (.61)
Accuracy
Confidence
Confidence in the Veracity Judgment
A similar 2 (presentation modality: video vs. transcript) x 2 (consequentiality:
serious vs. benign) between-subjects ANOVA was conducted with confidence of veracity
judgment as the dependent variable was conducted to explore the influence of
36
presentation modality and consequentiality on confidence. The results revealed no
significant main effects nor interactions, Fs(1, 139) < 1, ps > .05. Next, participants’
confidence in their veracity judgments was broken down into confidence for true and
false events. A 2 (memory type: true vs. false) x 2 (presentation modality: video vs.
transcript) x 2 (consequentiality: serious vs. benign) mixed ANOVA was conducted with
memory type varying within-subjects and confidence in their veracity judgments as the
dependent variable. The results revealed no significant main effects nor interactions,
Fs(1, 139) < 1.82, ps > .05. Interestingly, even though participants in the transcript
condition were more accurate, confidence in their judgments did not differ significantly
from the participants in the video condition.
Relation Between Veracity Judgment Accuracy and Confidence
To explore the relation of accuracy and confidence several correlations were
conducted. There was no significant correlation between overall veracity judgment
accuracy and veracity judgment confidence, r = .04, p > .05. Additionally, true event
veracity judgment accuracy was not significantly correlated to confidence in true event
judgment, r = .03, p > .05. Similarly, false event veracity judgment accuracy was not
significantly correlated to confidence in false event judgment, r = .08, p > .05.
Factors Related to Veracity Judgment
Perceived Characteristics of True and False Memory Reports
Participants rated the clarity, plausibility, typicality, consistency, adults’
confidence, distinctiveness, and ease of retrieval of each memory report. Average
perceived memory characteristics ratings were created separately for true and false
37
events. The ratings were then entered into an exploratory 2 (presentation modality: video
vs. transcript) x 2 (consequentiality: serious vs. benign) x 2 (memory type: true vs. false)
mixed MANOVA with memory type varying within-subjects. The results revealed a
significant multivariate main effect of presentation modality, Wilk’s λ = .75, F(7, 133) =
6.33, p < .001, ηp2 = .25 (see Table 4), indicating an overall difference in perceived
characteristics of memory reports between the video and the transcript condition. The
multivariate main effect of memory type was also significant, Wilk’s λ = .63, F(7, 133) =
11.11, p < .001, ηp2 = .37, suggesting an overall difference in perceived memory
characteristics between true and false memory reports. There was also a significant
multivariate presentation modality by memory type interaction, Wilk’s λ = .77, F(7, 133)
= 5.55, p < .001, ηp2 = .23. No other multivariate effects were found, Fs(7, 133) < 1, ps >
.05. The multivariate main effect of consequentiality was not significant, F(7, 133) =
1.32, p > .05.
Table 4
Effects of Presentation Modality and Consequentiality on True/False Memory
Characteristic Ratings
Presentation Modality
Consequentiality
Video
Transcript
Benign
Serious
Total
(n = 71)
(n = 72)
(n = 66)
(n = 77)
(N = 66)
Clarity
3.42 (.77)
3.49 (.83)
3.49 (.83)
3.42 (.80)
3.45 (.81)
Plausibility
3.89 (.78)
4.00 (.90)
3.87 (.82)
4.01 (.86)
3.94 (.84)
Typicality
4.14 (.70)
4.10 (.81)
4.05 (.86)
4.18 (.65)
4.12 (.75)
Consistency
3.80 (.85)
3.64 (.88)
3.72 (.91)
3.71 (.83)
3.72 (.86)
Adults’
3.39 (.84)
3.23 (.83)
3.26 (.84)
3.36 (.83)
3.31 (.83)
True Events
38
Presentation Modality
Consequentiality
Video
Transcript
Benign
Serious
Total
(n = 71)
(n = 72)
(n = 66)
(n = 77)
(N = 143)
Distinctiveness
3.79 (.84)
3.91 (.84)
3.80 (.85)
3.90 (.81)
3.85 (.82)
Ease of
3.04 (.80)
3.36 (.78)
3.23 (.73)
3.18 (.87)
3.20 (.80)
3.84 (.97)
3.28 (.91)
3.61
3.51 (.91)
3.56 (.98)
Confidence
Retrieval
False Events
Clarity
(1.06)
Plausibility
4.19 (.83)
3.91 (.84)
4.02 (.89)
4.08 (.80)
4.05 (.84)
Typicality
4.36 (.71)
3.98 (.78)
4.21 (.75)
4.13 (.78)
4.17 (.77)
Consistency
4.18 (.85)
3.55 (.87)
3.83 (.89)
3.89 (.93)
3.86 (.91)
Adults’
4.13 (.84)
3.20 (.91)
3.67 (.98)
3.66 (1.00)
3.66 (.99)
3.85 (.90)
3.33 (.94)
3.59
3.59 (.91)
3.59 (.95)
3.44 (.97)
3.52 (1.00)
Confidence
Distinctiveness
(1.01)
Ease of
Retrieval
3.92 (.94)
3.13 (.90)
3.61
(1.03)
Simple effect analyses were conducted to further examine the significant
multivariate presentation modality by memory type interaction. In the transcript
conditions, the participants rated the perceived memory characteristics of true and false
memories differently, Wilk’s λ = .64, F(7, 65) = 5.31, p < .001, ηp2 = .36. However, an
examination of the univariate effects indicated that the difference was only on perceived
distinctiveness: the participants who read the transcripts rated the true memories as being
more distinctive than the false memories, F(1, 71) = 20.50, p < .001, ηp2 = .22. No
39
significant univariate differences in perceived clarity, plausibility, typicality, consistency,
adults’ confidence, or ease of retrieval of each memory report were found between the
true and false memories, Fs(1, 71) < 3.83, ps > .05. A different pattern emerged for the
video conditions: the participants that watched the videotaped memories also rated the
perceived memory characteristics differently when judging true or false events, Wilk’s λ
= .49, F( 7, 64) = 9.38, p < .001, ηp2 = .51. However, examination of the univariate
effects indicated that the participants who watched the videos rated the false memories
higher in perceived clarity (F(1, 70) = 7.66, p < .01, ηp2 = .10), plausibility (F(1, 70) =
4.69, p < .05, ηp2 = .06), typicality (F(1, 70) = 4.06, p < .05, ηp2 = .06), consistency (F(1,
70) = 5.58, p < .05, ηp2 = .07), adults’ confidence level (F(1, 70) = 22.56, p < .001, ηp2 =
.24), and ease of memory retrieval (F(1, 70) = 35.75, p < .001, ηp2 = .34) compared to
videotaped true memories. Ratings of perceived distinctiveness did not vary between true
or false events, F(1, 70) = .14, p > .05. Thus, only in the video conditions, participants
perceived the false memories as being higher in perceived clarity, plausibility, typicality,
consistency, adults’ confidence level, and ease of memory retrieval.
Based on the previous findings regarding the importance of perceived memory
characteristics, an interesting question arose: did participants who were relatively
accurate in their veracity judgments perceive the characteristics of the memory reports
differently from those who were less accurate? To answer this question, the participants
were divided into two groups on the basis of overall veracity judgment accuracy. Overall
veracity judgment accuracy was computed by averaging veracity judgment accuracy
across the four memory reports. For example, if a participant correctly classified 3 out of
40
4 memories their overall accuracy score would be .75 or 75%. To be classified as having
high memory judgment accuracy participants had to achieve an average accuracy score
greater than 50% whereas participants classified as having low memory judgment
accuracy had an average accuracy score equal to or less than 50%. A 2 (presentation
modality: video vs. transcript) x 2 (memory type: true vs. false) x 2 (memory judgment
accuracy: low vs. high) mixed MANOVA was conducted with memory type varying
within-subjects. The results revealed two significant multivariate main effects: memory
type, Wilk’s λ = .64, F(7, 133) = 10.57, p < .001, ηp2 = .36, and presentation modality,
Wilk’s λ = .75, F(7, 133) = 6.48, p < .001, ηp2 = .25. There were also two significant
multivariate interactions: presentation modality by memory type, Wilk’s λ = .78, F(7,
133) = 5.53, p < .001, ηp2 = .23, which was similar to what was found in the previous
analysis, and a memory type by memory judgment accuracy interaction, Wilk’s λ = .67,
F(7, 133) = 9.56, p < .001, ηp2 = .34. No other significant multivariate main effects nor
interactions were found, Fs(7, 133) < 1.94, ps > .05.
Simple effect analyses for the significant multivariate interaction between
presentation modality and memory type demonstrated the same pattern as the previous
MANOVA, Wilk’s λ = .49, F(7, 64) = 9.38, p < .001, ηp2 = .51.
Simple effect analysis for the significant multivariate memory type by memory
judgment accuracy interaction revealed that participants with high memory judgment
accuracy rated the memories differently when judging true or false reports, Wilk’s λ =
.49, F(7, 54) = 7.98, p < .001, ηp2 = .51. Univariate analyses indicated that participants
with high memory judgment accuracy rated true memories higher in perceived clarity
41
(F(1, 60) = 18.15, p < .001, ηp2 = .23), plausibility (F(1, 60) = 16.98, p < .001, ηp2 = .22),
typicality (F(1, 60) = 18.03, p < .001, ηp2 = .23), consistency (F(1, 60) = 19.42, p < .001,
ηp2 = .25), adults’ confidence (F(1, 60) = 4.49, p < .05, ηp2 = .07), and distinctiveness
(F(1, 60) = 38.24, p < .001, ηp2 = .39). Ease of retrieval was rated similarly for both true
and false memory reports, F(1, 60) = 2.58, p > .05 (see Table 5). Similarly, participants
with low memory judgment accuracy also rated the memories differently when judging
true or false memory reports, Wilk’s λ = .48, F(7, 75) = 11.82, p < .001, ηp2 = .53.
However, participants with low memory judgment accuracy rated false memories higher
in perceived clarity (F(1, 81) = 22.26 p < .001, ηp2 = .22), plausibility (F(1, 81) = 28.72, p
< .001, ηp2 = .26), typicality (F(1, 81) = 25.01, p < .001, ηp2 = .24), consistency (F(1, 81)
= 25.17, p < .001, ηp2 = .24), adults’ confidence (F(1, 81) = 49.27, p < .001, ηp2 = .38),
distinctiveness (F(1, 81) = 4.07, p < .05, ηp2 = .05), and ease of retrieval (F(1, 81) =
29.12, p < .001, ηp2 = .26). Thus, unlike participants with low memory veracity judgment
accuracy, participants with high memory veracity judgment accuracy, rated true
memories in line with the predictions of the Source Monitoring Framework.
Finally, difference scores were calculated between each set of the perceived true
and false memory characteristics ratings (difference in clarity, etc.) for each participant.
Exploratory correlations between the difference scores and the overall veracity judgment
accuracy and confidence were computed. The results indicated that perceived clarity,
plausibility, typicality, consistency, adults’ confidence, distinctiveness, and ease of
memory retrieval were significantly positively correlated with accuracy; however, the
42
perceived memory characteristics were not significantly correlated with confidence (see
Table 6).
Table 5
Memory Characteristic Ratings for True/False Memory Reports by Participants with Low
and High Memory Judgment Accuracy
Memory Judgment Accuracy
Low
High
Total
(n = 82)
(n = 61)
(N = 143)
True
False
True
False
True
False
3.19
3.80
3.81
3.22
3.45
3.56
(.76)
(.87)
(.75)
(1.02)
(.81)
(.98)
3.72
4.27
4.25
3.73
3.94
4.05
(.80)
(.75)
(.80)
(.85)
(.84)
(.84)
3.93
4.37
4.09
3.90
4.12
4.17
(.75)
(.66)
(.68)
(.83)
(.75)
(.77)
3.44
4.10
4.09
3.55
3.72
3.86
(.88)
(.89)
(.68)
(85)
(.86)
(.91)
Adults’
3.03
3.88
3.69
3.38
3.31
3.66
Confidence
(.79)
(.87)
(.74)
(1.07)
(.83)
(.99)
Distinctiveness
3.57
3.82
4.22
3.28
3.85
3.59
(.82)
(.84)
(.67)
(1.01)
(.82)
(.95)
Ease of
2.99
3.72
3.48
3.25
3.20
3.52
Retrieval
(.81)
(.90)
(.70)
(1.06)
(.80)
(1.00)
Clarity
Plausibility
Typicality
Consistency
43
Table 6
Correlations of the Difference Scores for Characteristics of Memory
Accuracy
Confidence
Clarity
.54 ***
.10
Plausibility
.57***
.08
Typicality
.54***
-.12
Consistency
.58***
-.06
Adults’ Confidence
.57***
.01
Distinctiveness
.59***
.12
Ease of Retrieval
.48***
.12
Difference Scores
*p < .05. **p < .01. ***p < .001.
Importance of Cues in Veracity Judgment
Participants rated the importance of the various memory cues after they
completed the memory judgment task for all four memory reports. In addition to
perceived clarity, plausibility, typicality, consistency, adults’ confidence, distinctiveness,
and ease of memory retrieval participants also rated the importance of amount of
information recalled, adults’ facial expression, vocal intonation, and non-facial body
language. Participants that watched the videotaped memory reports had access to the
latter 3 characteristics, whereas the participants that read the transcripts did not have
access to those characteristics; thus, they judged how important those characteristics
would have been to their judgments. To reduce the number of variables, the ratings were
entered into a principal component analysis with Varimax rotation. Three components
emerged with Eigenvalues greater than 1. The three components were interpreted as
Importance of Verbal Cues, Importance of Nonverbal Cues, and Importance of
44
Plausibility Cues (see Table 7). The three components collectively accounted for 58.01%
of the variance. Reliability analysis indicated that the internal reliability of the emerged
components were Cronbach’s Alpha = .78 for Importance of Verbal Cues, Cronbach’s
Alpha = .65 for the Importance of Nonverbal Cues, and Cronbach’s Alpha of .58 for the
Importance of Plausibility Cues. Three composite cue importance scores were then
created by averaging the items with loadings higher than .50 on each component.
To explore potential difference in cue importance ratings across the conditions, a 3 (cue
type: verbal vs. nonverbal vs. plausibility) x 2 (presentation modality: video vs.
transcript) x 2 (consequentiality: benign vs. serious) mixed factorial ANOVA was
conducted with cue type varying within-subjects and importance of cue type as the
dependent variable. There was a significant main effect of cue type, F(2, 278) = 6.10, p <
.01, ηp2 = .04 (see Table 8). The cue type by presentation modality interaction was also
significant, F(2, 278) = 5.47, p < .01, ηp2 = .04. In addition, the cue type by
consequentiality interaction was significant, F(2, 278) = 3.23, p <. 05, ηp2 = .02. The cue
type by presentation modality by consequentiality interaction was not significant, F(2,
278) = .77, p > .05. No other significant effects were found, Fs(1, 139) < 2.18, ps > .05.
Interestingly, simple effects analysis for the significant cue type by presentation
modality interaction revealed that participants who read the transcripts (i.e., those who
did have access to nonverbal cues) rated Importance of Nonverbal Cues higher compared
to participants who watched the videos and actually had access to the nonverbal cues,
F(1, 141) = 10.41, p < .01, ηp2 = . 07. Participants in the video and transcript conditions
did not rate Importance of Verbal Cues (F(1, 141) = .16, p > .05) and Importance of
45
Table 7
Summary of Principle Component Analysis on Potential Predictors of Memory Judgment
Factor Names and the High Loading
Factor Loadings
Variables
Importance of Verbal Cues (Eigenvalue =
2.81)
Importance of Ease or Difficult Retrieval
.81
Importance of Distinctiveness
.79
Importance of Adults’ Confidence
.68
Importance of Clarity
.62
Importance of Amount of Information
.61
Recalled
Importance of Nonverbal Cues (Eigenvalue
= 1.94)
Importance of Vocal Intonation
.80
Importance of Facial Expression
.75
Importance of Non-facial Body Language
.67
Importance of Plausibility (Eigenvalue =
1.64)
Importance of Typicality
.77
Importance of Plausibility
.74
Importance of Consistency
.52
Plausibility Cues (F(1, 141) = .33, p > .05) differently. Simple effect analyses also
indicated that participants that watched the videos rated Importance of Verbal Cues the
highest compared to Importance of Nonverbal Cues or Importance of Plausibility Cues,
F(2, 140) = 5.26, p < .01, ηp2 = .07. Participants that read the transcripts rated Importance
46
of Nonverbal Cues higher than Importance of Plausibility Cues, F(2, 142) = 6.15, p < .01,
ηp2 = .08. There were no other significant differences.
Table 8
Effects of Presentation Modality and Consequentiality on Importance Ratings of Memory
Cues
Presentation Modality
Consequentiality
Video
Transcript
Benign
Serious
Total
(n= 71)
(n = 72)
(n = 66)
(n = 77)
(N = 143)
4.93 (.72)
4.88 (.65)
4.93 (.63)
4.89 (.73)
4.91 (.68)
4.66 (.70)
5.01 (.60)
4.69 (.70)
4.96 (.63)
4.83 (.67)
4.66 (.60)
4.74 (.67)
4.66 (.60)
4.73 (.66)
4.70 (.63)
Importance
of Verbal
Cues
Importance
of
Nonverbal
Cues
Importance
of
Plausibility
Cues
Additionally, simple effects analysis for the significant cue type by
consequentiality interaction revealed that the consequentiality condition significantly
affected their ratings of cue importance, F(2, 284) = 5.70, p < .01, ηp2 = .04. Participants
in the benign consequence condition rated Importance of Verbal Cues higher than both
the Importance of Nonverbal Cues and Plausibility Cues, F(2, 130) = 5.18, p < .01, ηp2 =
.01. Participants in the serious consequence condition rated Importance of Nonverbal
47
Cues as higher than Importance of Plausibility Cues, F(2, 152) = 3.79, p < .05, ηp2 = .05.
There was no significant difference between Importance of Verbal and Nonverbal Cues.
Exploratory correlation coefficients between the cue importance ratings and the
accuracy and confidence of the veracity judgments were calculated. The results indicated
that cue importance ratings were not significantly correlated with accuracy, but weakly
correlated with confidence of veracity judgments, indicating that the more confident
participants are in their veracity judgments the more importance they rate Verbal and
Plausibility Cues (see Table 9). There was no gender difference in cue importance
ratings, despite that women were slightly more accurate at veracity judgments, Fs < 1.29,
ps > .05 (see Table 10).
Table 9
Correlations Between Accuracy and Confidence with Importance of Cues
Importance of
Importance of
Importance of
Verbal Cues
Nonverbal Cues
Plausibility Cues
Overall
-.06
.10
.06
True
.01
.04
.04
False
-.10
.12
.06
Overall
.17*
.08
.21*
True
.20*
.11
.24**
False
.08
.02
.10
Accuracy
Memories
Confidence
*p < .05. **p < .01.
48
Table 10
Ratings of Importance of Cues by Gender
Gender
Importance of
Verbal Cues
Importance of
Nonverbal Cues
Importance of
Plausibility Cues
Male
Female
Total
(n = 40)
(n = 103)
(N = 143)
5.01 (.65)
4.87 (.69)
4.93 (.68)
4.80 (.67)
4.83 (.67)
4.64 (.63)
4.72 (.63)
4.70 (.63)
4.91 (.68)
Group Judgments
The accuracy and confidence of veracity judgments were analyzed at the group
level. For group level analyses, judgments following group discussion were aggregated to
measure each group’s (n = 31) decision, that is, participants’ judgments within their
respective group were averaged. Two sets of group judgment scores were created: predeliberation average, which provided a baseline to which the effect of deliberation could
be compared, and post-deliberation group average. Two groups (nine participants total)
did not reach a consensus or ran out of time within the given time limit and were thus
partially excluded from the analyses, meaning their judgment scores were created from
three instead of four events.
Accuracy of the Veracity Judgment
It was hypothesized that groups would be more accurate following deliberation,
with groups that read the transcripts with a serious consequence attached to their veracity
49
judgments being the most accurate following deliberation. To test this hypothesis a 2
(presentation modality: video vs. transcript) x 2 (consequentiality: serious vs. benign) x 2
(deliberation: pre vs. post) mixed ANOVA was conducted with deliberation varying
within-subjects and veracity judgment accuracy as the dependent variable. The analysis
revealed no significant main effects or interaction, Fs(1, 27) < 2.53, ps > .05, (see Table
11).
In addition, a 2 (presentation modality: video vs. transcript) x 2 (consequentiality:
serious vs. benign) x 2 (deliberation: pre vs. post) x 2 (memory type: true vs. false) mixed
ANOVA was conducted with deliberation and memory type varying within-subjects and
veracity judgment accuracy as the dependent variable. The deliberation by memory type
interaction was significant, F(1, 27) = 4.65, p < . 05, ηp2 = .15. No other main effects or
interactions were significant, Fs (1, 27) < 3.19, ps > .05. Simple effects analyses
suggested that for true memory reports, participants were just as accurate in predeliberation (M = .56, SD = .21) compared to post-deliberation (M = .55, SD = .37), F(1,
30) = .07, p > .05. For false events however, participants were more accurate in postdeliberation compared (M = .70, SD = .36) to pre-deliberation (M = .54, SD = .20), F(1,
30) = 7.00, p < .05, ηp2 = .19. Simple effects analyses revealed that veracity judgment
accuracy for true memory reports (M = .56, SD = .21) and false memory reports (M = .54,
SD = .20) was not significantly different pre-deliberation, F(1, 30) = .22, p > .05.
However, participants were more accurate judging false memories (M = .70, SD = .36)
compared to true memories (M = .55, SD = .37) post deliberation, F(1, 30) = 4.03 p = .05,
ηp2 = .12.
50
Table 11
The Effects of Presentation Modality, Consequentiality, Memory Type, and Collaboration on Accuracy and Confidence of
Memory Report Veracity Judgments
Pre Deliberation
Presentation Modality
Consequentiality
Video
Transcript
Benign
Serious
Total
(n = 16)
(n = 15)
(n = 15)
(n = 16)
(N = 31)
Overall Accuracy
.50 (.19)
.60 (.12)
.53 (.16)
.57 (.17)
.55 (.16)
True Event
.55 (.24)
.58 (.19)
.53 (.23)
.59 (.20)
.56 (.21)
False Event
.45 (.23)
.63 (.11)
.54 (.16)
.54 (.23)
.54 (.20)
4.22 (.29)
4.18 (.16)
4.20 (.25)
4.20 (.22)
4.20 (.23)
True Event
4.16 (.41)
4.22 (.28)
4.16 (.38)
4.22 (.34)
4.19 (.35)
False Event
4.28 (.35)
4.15 (.20)
4.25 (.36)
4.19 (.21)
4.21 (.29)
Overall
Confidence
51
Post Deliberation
Presentation Modality
Consequentiality
Video
Transcript
Benign
Serious
Total
(n = 16)
(n = 15)
(n = 15)
(n = 16)
(N = 31)
Overall Accuracy
.57 (.30)
.67 (.31)
.55 (.35)
.68 (.25)
.62 (.30)
True Event
.53 (.39)
.57 (.37)
.47 (.40)
.63 (.34)
.55 (.37)
False Event
.65 (.36)
.77 (.37)
.66 (.42)
.75 (.32)
.70 (.36)
4.66 (.43)
4.64 (.38)
4.61 (.37)
4.69 (.44)
4.65 (.40)
True Event
4.79 (.43)
4.75 (.54)
4.81 (.57)
4.73 (.38)
4.77 (.48)
False Event
4.50 (.64)
4.54 (.48)
4.40 (.50)
4.64 (.60)
4.52 (.56)
Overall
Confidence
52
Thus, group deliberation did not significantly affect the overall accuracy of
veracity judgments; however, after the deliberation the groups were more accurate at
judging the false memory reports.
Confidence of the Veracity Judgment
An exploratory 2 (presentation modality: video vs. transcript) x 2
(consequentiality: serious vs. benign) x 2 (deliberation: pre vs. post) mixed ANOVA was
conducted with deliberation varying within-subjects and confidence in veracity
judgments as the dependent variable. The analysis revealed a significant main effect of
deliberation, F(1, 27) = 45.96, p < .001, ηp2 = .63, indicating that group deliberation
increased confidence in memory veracity judgments. No other significant main effects
nor interactions were found, Fs < 1, ps > .05.
To further examine the effect of deliberation on confidence in memory veracity
judgments a 2 (presentation modality: video vs. transcript) x 2 (consequentiality: serious
vs. benign) x 2 (deliberation: pre vs. post) x 2 (memory type: true vs. false) mixed
ANOVA was conducted with deliberation and memory type varying within-subjects and
confidence in veracity judgments as the dependent variable to assess the effects of
deliberation on the confidence of true/false memory veracity judgments. The main effect
of deliberation was again significant, F(1, 27) = 41.23, p < .001, ηp2 = .60. In addition, a
significant deliberation by memory type interaction emerged, F(1, 27) = 4.60, p < .05, ηp2
= .15. Simple effects analysis revealed that for both true and false memories, participants
were more confident post-deliberation compared to pre-deliberation, F(1, 30) = 52.19, p
< .001, ηp2 = .64; F(1, 30) = 8.43, p < .01, ηp2 = .22. Simple effects analyses revealed that
53
confidence in veracity judgments for true and false memory reports was not significantly
different pre-deliberation, F(1, 30) = .10, p > .05. However, participants were more
confident in true events compared to false events post-deliberation, F(1, 30) = 5.17, p <
.05, ηp2 = .15.
Thus, despite that group deliberation did not increase the overall accuracy (and
only marginally increased the accuracy of judging false memories), group deliberation
significantly increased the level of confidence in the veracity judgments across the board.
Exploratory correlation coefficients were calculated between aggravated predeliberation veracity judgment accuracy and confidence, and between post-deliberation
veracity judgment accuracy and confidence. The only significant correlation emerged
was between accuracy and confidence in post-deliberation judgments of false memories
(r = .35, p < .05), indicating that following group discussion of false memories as
accuracy increases so does confidence.
54
Chapter 4
DISCUSSION
Understanding how people judge the veracity of true and false memories in other
people has both practical and theoretical implications. In the present study, the effects of
presentation modality, consequentiality, and collaboration on accuracy and confidence of
memory veracity judgments were examined. In addition, how memory characteristics
(clarity, plausibility, typicality, consistency, adult’s confidence, distinctiveness, and ease
of retrieval) and cues for veracity (verbal, nonverbal, and plausibility) relate to accuracy
and confidence of judgments were explored.
Overall participants demonstrated slightly above chance memory veracity
accuracy (55%) which is consistent with the notion that judging memory veracity is
similar to judging deception detection (54% accuracy rate, Bond & DePaulo, 2006).
Consistent with the hypothesis, the results of the present study showed that participants in
the transcript conditions were more accurate in the veracity judgments than those in the
video conditions. More detailed analyses further indicated that the effect of presentation
modality on veracity judgment accuracy was mainly due to the difference in the accuracy
of judging false memories. Compared to those who watched the videotaped memory
reports, participants who read the transcripts were more accurate in judging false
memories, but no more accurate in judging true memories. Interestingly, only the
participants in the video conditions were more accurate at judging true than false
memories. This finding paralleled Vrij’s (2000) finding that people were better at
55
detecting the truth than lies. Additionally, this finding also paralleled Levine, Park, and
McCornack’s (1999) observation of the “veracity effect” (people’s tendency to judge
messages as truthful).
The primary difference between the video and transcript conditions was that only
in the video condition, participants had access to nonverbal cues such as facial
expression, vocal intonation, and non-facial body language. Because individuals who
recall false memories genuinely believe in the “memory”, the typical nonverbal cues that
may be indicative of intentionally reporting false statements (i.e., lies) may not be present
in false memory reports. Relying on nonverbal cues in veracity judgments may therefore
lead to the lowered accuracy observed; thus, leading to similar results of Burgoon et al.
(2008) and Vrij (2000) in regards to deception detection. This interpretation is consistent
with the finding that the participants in the present study generally rated nonverbal cues
to be very important for their veracity judgment (M = 4.83, SD = .67 on a 6-point scale, 1
= very unimportant to 6 = very important). Interestingly, participants who did not have
access to nonverbal cues (i.e., those in the transcript conditions) considered it to be even
more important than participants who watched the videotaped memory reports.
In addition to the manipulations to potentially influence veracity judgment
accuracy, participants also rated the perceived memory characteristics of the true and
false memories. According to the SMF, average differences in the characteristics of
memories from different sources provide the crucial information based on which source
attributions can be made. If interpersonal reality monitoring works on a similar
mechanism, the perceived characteristics of true and false memory reports should be
56
related to the veracity judgments in the present study. Several findings from the present
study were consistent with this reasoning. For example, in the video conditions where the
overall accuracy of veracity judgments was lower, participants rated the false memories
higher in perceived clarity, plausibility, typicality, consistency, adults’ confident level,
and ease of memory retrieval compared to true memories. It is possible that such a
reversed pattern of perceived memory characteristics was responsible for the increased
likelihood of judging false memory reports as true, thus the reduced accuracy. This
finding is also consistent with the SMF because memories that were rated higher on the
perceived memory characteristics were more likely to judged as true. It should be noted
however, that this last point is inclusive, because it is also possible that the participants
made their veracity judgments first, and then rated the memory characteristics in
accordance with their veracity judgments.
Another related finding was that participants with higher veracity judgment
accuracy rated true memories higher in perceived clarity, plausibility, typicality,
consistency, adults’ confidence, and distinctiveness. However, participants with low
memory judgment accuracy showed an opposite pattern; they rated false memories higher
in perceived clarity, plausibility, typicality, consistency, adults’ confidence,
distinctiveness, and ease of retrieval than true memories. Following a similar logic, it is
possible that participants who were more accurate in their veracity judgments because
they correctly perceived true memories as more clear, plausible, etc. compared to false
memories. However, it is also possible that the perceived memory characteristics were
influenced by veracity judgments, in which case the direction of causality would be
57
reversed. Perhaps the participants who were more accurate in veracity judgments had
superior interpersonal source/reality monitoring skills and it is the difference in
source/reality monitoring skills between participants with high and low veracity judgment
accuracy that influenced the ratings of the memory characteristics.
Unlike participants in the benign consequence conditions, who rated verbal cues
as more important than both nonverbal cues and plausibility cues, participants in the
serious consequence conditions rated nonverbal cues as more important than plausibility
cues. Despite this difference in cue importance ratings, the consequentiality manipulation
did not affect the accuracy or confidence of the veracity judgments in the present study. It
is possible that the lack of significant effect resulted from a relatively weak manipulation
of the consequentiality variable. A more interesting possibility, however, is that perhaps
the relation between consequentiality and veracity judgment accuracy is more complex
than initially thought. For example, assume that participants in the serious consequence
conditions did adopt a stricter criterion than those in the benign conditions, and a more
strict criterion may translate into higher or lower accuracy.
Group deliberation in the present study did not increase the overall level of
veracity judgment accuracy. However, the judgment of false memories became more
accurate after group deliberation. Another interesting finding was that the confidence of
the veracity judgment increased following group deliberation. Perhaps being a member of
a group and engaging in the discussion in order to reach a consensus about the veracity of
the memory report made participants more confident in the decisions; after all, a group
consensus means that the decision was supported by all members of the group. Moreover,
58
the findings reaffirm the setup of our jury system because reaching a consensus not only
improved accuracy (in regards to false events) but raised confidence as well.
The present study has several limitations. Vrij (2004) noted that when people
make deception detection judgments they base the judgment on their own knowledge;
meaning, people compare what they know with a person’s statement. This finding is
relevant to the extent that participants in the present study cross-checked the information
in the memory reports with their own knowledge. If participants held incorrect eventrelated knowledge such as McDonald’s never had birthday crowns participants may make
the mistake of calling a true memory false. For example, one of the two Birthday Party at
McDonald’s memory reports is of concern because a number of participants listed that
McDonald’s does not have crowns (a detail given in the true McDonald’s Birthday Party
memory report) and thus the memory must be false; however, McDonald’s did have
crowns (participants in our study may have been too young to remember because
McDonald’s no longer has crowns). If participants knew prior to judging these memory
reports that McDonald’s did have crowns perhaps true event accuracy would have been
higher in both pre- and post-deliberation. To address this potential problem, future
research should include procedures that assess or manipulate participants’ knowledge
related to events described in memory reports.
The participants in the present study rated the characteristics of the memory
reports following veracity judgment. Some interesting connection between perceived
memory characteristics and veracity judgments were uncovered, however, the
interpretation of the relation was ambiguous, partly because there was no “objective”
59
measures of characteristics of true and false memories. Future research should include
more objective measures of memory characteristics, and compare them to the perceived
memory characteristics ratings obtained simultaneously with the veracity judgments. This
would help disentangle some of the ambiguities in interpreting the relation between
veracity judgment accuracy and the perceived memory characteristics.
The pool of true and false events used in the present study was rather small, and
they were not entirely selected at random. Therefore, it was not clear that these memory
reports were representative of true and false memory reports in general. To increase the
generalizability, future research should employ a wider range of true and false memory
reports. Additionally, with the use of more memory reports, it would be possible to use
signal detection theory indices that would separate sensitivity (the “real” accuracy) and
the response criterion. With only two events in each category, it is unrealistic to use SDT
indices because the estimates of hit rate and false alarm rate would be too unstable.
Another interesting possibility is to ask participants to make indirect veracity
judgments of true and false memories. To the extent that reliable indicators of true and
false memories can be identified, it would be interesting to examine whether participants
would fare better in assessing other people’s memories indirectly than making veracity
judgments directly (e.g., Vrij et al., 2001). Perhaps participants would be better at judging
the presence or absence of indicators of false memory rather than false memory itself.
Several aspects of the group deliberation processes could be improved in future
research. The influence of the forepersons’ view on the final groups’ decision should be
examined. Since the foreperson is the designated facilitator of the discussion, his/her
60
opinion could be given more weight during the group deliberation process by fellow
group members. Additionally, participants were young undergraduate students in
psychology (mostly). They were not representative of people from community; thus, they
do not constitute typical “jurors” in criminal and/or civil cases. Also, the group
deliberation process was limited to 5 minutes, which may not have been enough time for
the deliberation to exert its effect (if any) on the accuracy rates. Thus, it is difficult to
generalize the group deliberation findings of this study to jury situations in the real world.
Future research should strive for a more representative sample as well as more time for
deliberation.
The relatively small sample size, especially for group level analyses, may have
been responsible for the lack of significant differences. Thus, future studies should have
an adequate number of participants to have a reasonable chance of uncovering small
effects.
61
Appendix A
Transcriptions
Transcript # 1
Going to a hospital for an injury
Not much. I didn’t think I’d ever been to the hospital for an injury. I don’t know why like
hurting my knees I would have gone cuz I know I’ve never broken a bone or I’ve never
sprained anything. Um, so when it comes to hurt my knees I don’t think it was because I
fell down or something I mean I played sports a lot when I was a kid, but just going to the
hospital I don’t. I mean I can picture me crying I can picture me hurt, but not badly hurt,
I’ve never had stiches…so I …surprised I went to the hospital. It seems really for some
reason I picture myself in the front of our house, um at the same house where the accident
was that we’re … but I was in the back with the dog ..that’s where I see myself. I see it in
the afternoon, and it’s sunny. Ah and I just seem myself in the front of our house. And
that’s all I can think of, like just that situation I don’t, I don’t recall at all going to a
hospital like a um you know like a big hospital with doctors and stuff. I, I can picture
going to our pediatrician or something but I think , I can kind of picture my knees all
scrapped up and like and like bloody but but just like ah something like when you fall.
You know just…ah your knees scratched I can picture that um I just …I can see my
knees like scrapped up um and …Um I can picture like me, what I look like, like blonde
hair ponytail. Like crying like I remember crying. Like I could I mean but then ..about the
event. Just like vague but I don’t remember both my parents being in the hospital with
me.
62
Transcript # 2
Going to a hospital for an injury
I uh, was pretty dim the first time I tried to remember it um and it's not all that much
better now, um. I uh, um, I sort of have the images, but unlike the first memory where it
was sort of, things that I remembered made sense from my perspective from sitting inside
the car. The images I get when I think of this are more um, most of them being from
another person watching it unfold so that makes me less confident XXXX, tell you what I
see. Um, uh, I think it was my, want to say it was my dad. I um, we were playing
together uh and I remember or I think I remember gravel um that uh was kind of like a
rocky base around the uh the a swing set slide type of thing. Um, I remember going to
the hospital about this age, but I don’t, I'm not at all that confident that it's in relation to
this event, uh, because I remember getting a shot, um, getting a shot in my uh, thigh and
not being real happy about it. Um, I don't remember any of the kids there um, so don't
think it was uh, so I don't think it happened like during the uh I went to a to a day care for
half a day uh, when I was about this old. Um so, I don't think it happened during that, it
must have happened on the weekend, I don't remember any other kids there. Uh, I just
remember me, me and my dad. Um I remember being on the swings and uh, um trying to
get going real fast and then jump out the front. Uh and uh, land and fall and getting uh
scraping the side of my face really badly. Um, and I remember going to the, to uh, I
couldn’t say if to the hospital or to the doctor um. But I guess they were probably one in
the same to me when I was that age. But um going somewhere where um, somebody um,
was picking the little pieces of gravel, little pieces of rock out of the cut and um. And
again I remember my dad. So, I'm wondering if I just over crying substituted the swing
for the slide. I think that was what I was referring to, um. Not specifically, again I, I
don't remember any of the kids or anything at the playground so, um which makes me
think it must have been in the night or it must have been on the weekend um and. No, not
that confident about it. Things were very bright, um which makes me think of the
summer or, the summer or spring. Um, um, I think that uh, I think I was wearing shorts
63
because I kind of vaguely remember at the doctor or the hospital or wherever it was um
also having one of my knees scrubbed. Um, so I probably had shorts on. Um, I don’t
really remember anything about the parent about um my dad’s reaction or anything. Um,
I actually don’t even remember my dad except for um um or I wouldn’t be certain it was
my dad and not my mom because I remember my dad at the hospital or doctor so I’m
assuming that he was also the one at the park. Don’t think so.
Transcript # 3
Birthday party at McDonald’s
I can imagine walking into McDonalds and my older sister would go straight to the
register to ordering food whereas our whole family would go straight to the table, sitting
there. And me and my two sisters that were about my age would be like, sitting there I
guess we could smell the food because it it smelled really good in that restaurant sense.
And we said, we would all say how good this food smelled and XXXX And just me and
my sisters would sit there talk about waiting for the food to come. The toy was like, a
little toy car or something. It was in a box, a wrapped up box. And as, and I think I tore
off the tore off the wrapping and opened the box, it was like a little Barbie or something,
I’m not sure. It was a generic Barbie I guess, and I was happy I guess. I was just like I
took the Barbie out of the box and stated combing its hair and stuff. And I just became
real XXXX with the Barbie and forgot about my meal that’s it. Uh this was at
McDonalds and that’s it. Well I don't remember having any kids around I just imagine
having all my family.
Transcript # 4
Birthday party at McDonald’s
Back in Florida and when McDonalds was all brown like shady brown and stuff, but it
was still cool cuz we got all of our friends got little McDonalds crown and stuff like that.
64
And then um my friends from kindergarten were there and um my neighbor, my nextdoor neighbor she was there, and my best friend, Jocelyn. And then um we just we had a
McDonalds birthday cake and the McDonalds birthday cake has these McDonalds
characters on it with the taste, it’s like sugary you know, and we all took some and then
we were eating cake and stuff and I remember running around and stuff like that. And
then um. Well the thing that I remembered was um there was this cage like you know
how they have playgrounds but this was like a cage and it was just in the middle of the
floor and you could bounce on it and it had springs on the bottom and then you could like
some sort of like …you fit like 5 or 6 people and we were like bouncing up and down in
the cage. And then, um, and then I don’t know. I had a hamburger because I don’t like
the pickles though. I took it off but.
65
Appendix B
Participant Information Questionnaire
Date _______________
Participant ID ______________, Group ______________
Condition: 1
2
3
4
Order # 1
2
3
Participant Information Questionnaire
1.) Your age ___________
2.) Gender
__________Male
__________Female
3.) Ethnicity
__________American Indian, Eskimo, or Aleut
__________Asian American or Pacific Islander
__________African American
__________Hispanic, Latino, or Spanish
__________Middle Eastern
__________Caucasian
__________Multi-ethnic
__________Other
4
66
4.) Primary Language
___________English
___________Other (explain) ______________________________________
5.) If Primary Language is not English, at what age did you begin to learn English?
__________
6.) Sometimes people may mistakenly remember something that did not actually happen.
In such cases they are not intentionally lying, but genuinely believe that the memory is
true. How confident are you in your ability to decipher if a memory reported by others is
true or false?
1
Very
Unconfident
2
Unconfident
3
Somewhat
Unconfident
4
Somewhat
Confident
5
Confident
6
Very
Confident
67
Appendix C
Memory Judgment Questionnaire
Participant ID ________________
Memory Judgment Questionnaire
Event #
1.
The memory is (circle one):
True
The confidence level of your true/false judgment is:
1
2
3
4
Very
Unconfident
Somewhat
Somewhat
Unconfident
Unconfident
Confident
False
2.
5
Confident
6
Very
Confident
3. Describe three reasons or clues for your true/false judgment (in the order of
importance):
1. _______________________________________________________________
2. _______________________________________________________________
3. _______________________________________________________________
4.
Whether the reported memory was clear
1
2
3
4
Very
Unclear
Somewhat
Somewhat
Unclear
Unclear
Clear
Whether the reported memory was plausible
1
2
3
4
Very
Implausible
Somewhat
Somewhat
Implausible
Implausible
Plausible
5
Clear
6
Very
Clear
5
Plausible
6
Very
Plausible
5.
6.
Whether the reported memory was typical of memory for an event of this type:
1
2
3
4
5
6
Very
Atypical
Somewhat
Somewhat
Typical
Very
Atypical
Atypical
Typical
Typical
68
7.
Whether the adult was consistent in his/her report:
1
2
3
4
Very
Inconsistent
Somewhat
Somewhat
Inconsistent
Inconsistent
Consistent
5
Consistent
Whether the adult was confident in what he/she reported:
1
2
3
4
5
Very
Unconfident
Somewhat
Somewhat
Confident
Unconfident
Unconfident
Confident
6
Very
Consistent
8.
6
Very
Confident
9.
Whether the reported memory was distinctive in that it included specific details:
1
2
3
4
5
6
Very
Indistinctive
Somewhat
Somewhat
Distinctive
Very
Indistinctive
Indistinctive Distinctive
Distinctive
10.
Whether it was easy for the adult to retrieve the memory:
1
2
3
4
5
Very
Difficult
Somewhat
Somewhat
Easy
Difficult
Difficult
Easy
6
Very
Easy
69
Appendix D
Perceived Cue Importance Questionnaire
Now you have made true/false judgments for 4 memory reports. Think about the criteria
that you used for making the judgments. In general, how important were each of the
following aspects to your true/false judgment?
1.
Whether the reported memory seemed clear
1
2
3
4
Very
Unimportant Somewhat
Somewhat
Unimportant
Unimportant
Important
Whether the reported memory seemed plausible
1
2
3
4
Very
Unimportant Somewhat
Somewhat
Unimportant
Unimportant
Important
5
Important
6
Very
Important
5
Important
6
Very
Important
2.
3.
type
Whether the reported memory seemed typical of the memory for an event of its
1
Very
Unimportant
2
Unimportant
3
Somewhat
Unimportant
4
Somewhat
Important
Whether the reported memory seemed consistent
1
2
3
4
Very
Unimportant Somewhat
Somewhat
Unimportant
Unimportant
Important
5
Important
6
Very
Important
5
Important
6
Very
Important
4.
5.
Whether the adult appeared confident in his/her report
1
2
3
4
5
Very
Unimportant Somewhat
Somewhat
Important
Unimportant
Unimportant
Important
6
Very
Important
Questions 6-8 ask about the non-verbal aspects of the memory report. If you have
watched the videos of the memory reports, answer the questions according to how each
of these was important to your true/false judgment. If you only read the transcripts of the
memory reports, answer the questions according to how each of these would have been
important to your true/false judgment.
6.
The facial expression of the adult
70
1
Very
Unimportant
2
Unimportant
3
Somewhat
Unimportant
4
Somewhat
Important
5
Important
6
Very
Important
The vocal intonation of the adult
1
2
3
Very
Unimportant Somewhat
Unimportant
Unimportant
4
Somewhat
Important
5
Important
6
Very
Important
4
Somewhat
Important
5
Important
6
Very
Important
5
Important
6
Very
Important
7.
8.
The non-facial body language
1
2
3
Very
Unimportant Somewhat
Unimportant
Unimportant
9.
The amount of information that was recalled
1
2
3
4
Very
Unimportant Somewhat
Somewhat
Unimportant
Unimportant
Important
10.
Whether the reported memory was distinctive in that it included specific details
1
2
3
4
5
6
Very
Unimportant Somewhat
Somewhat
Important
Very
Unimportant
Unimportant
Important
Important
11.
Whether it was easy or difficult for the adult to retrieve the memories
1
2
3
4
5
6
Very
Unimportant Somewhat
Somewhat
Important
Very
Unimportant
Unimportant
Important
Important
12.
Other (Please specify)
__________________________________________________
1
2
3
4
5
Very
Unimportant Somewhat
Somewhat
Important
Unimportant
Unimportant
Important
6
Very
Important
71
Appendix E
Post Deliberation Questionnaire
Post Deliberation Questionnaire
Answer the following questions for each memory report after the group deliberation.
These reflect your final vote.
Event #
1.
The memory is (circle one):
True
The confidence level of your true/false judgment is:
1
2
3
4
Very
Unconfident
Somewhat
Somewhat
Unconfident
Unconfident
Confident
False
2.
5
Confident
6
Very
Confident
3. Describe three reasons or clues for your true/false judgment (in the order of
importance):
1. _______________________________________________________________
2. _______________________________________________________________
3. _______________________________________________________________
72
Appendix F
Instructions for the Memory Judgment Task
Next you are going to watch 4 short episodes of adults reporting their memories of events
that might have happened to them before the age of 5 years. There are two possible
events: having a birthday party at McDonald’s, and going to a hospital for an injury. The
adults will be either reporting a true memory, meaning that the event actually did happen
in their childhood, or they could be reporting a false memory, in which case the event did
not really happen. Please note that in none of the cases were the adults intentionally
lying. When reporting a false memory, the adults erroneously believed that the event
actually occurred and sincerely “remembered” the event. Your task is to judge whether
each reported memory is true or false. You will complete a Memory Judgment
Questionnaire for each memory report.
When judging the veracity (i.e., true or false) of the memory reports, imagine that you are
engaged in a friendly contest to see who can make the most accurate judgments. Judge
the veracity of each memory report to the best of your ability.
Do you have any questions?
Instructions for the Memory Judgment Task
Next you are going to watch 4 short episodes of adults reporting their memories of events
that might have happened to them before the age of 5 years. There are two possible
events: having a birthday party at McDonald’s, and going to a hospital for an injury. The
adults will be either reporting a true memory, meaning that the event actually did happen
in their childhood, or they could be reporting a false memory, in which case the event did
not really happen. Please note that in none of the cases were the adults intentionally
lying. When reporting a false memory, the adults erroneously believed that the event
actually occurred and sincerely “remembered” the event. Your task is to judge whether
each reported memory is true or false. You will complete a Memory Judgment
Questionnaire for each memory report.
When judging the veracity (i.e., true or false) of the memory reports, imagine that you are
a member of a legal investigation team trying to find out if the remembered event
actually occurred or not because a serious crime is suspected to have occurred during the
event. Judge the veracity of each memory report to the best of your ability.
Do you have any questions?
73
Instructions for the Memory Judgment Task
Next you are going to read 4 short episodes of adults reporting their memories of events
that might have happened to them before the age of 5 years. There are two possible
events: having a birthday party at McDonald’s, and going to a hospital for an injury. The
adults will be either reporting a true memory, meaning that the event actually did happen
in their childhood, or they could be reporting a false memory, in which case the event did
not really happen. Please note that in none of the cases were the adults intentionally
lying. When reporting a false memory, the adults erroneously believed that the event
actually occurred and sincerely “remembered” the event. Your task is to judge whether
each reported memory is true or false. You will complete a Memory Judgment
Questionnaire for each memory report.
When judging the veracity (i.e., true or false) of the memory reports, imagine that you are
engaged in a friendly contest to see who can make the most accurate judgments. Judge
the veracity of each memory report to the best of your ability.
Do you have any questions?
Instructions for the Memory Judgment Task
Next you are going to read 4 short episodes of adults reporting their memories of events
that might have happened to them before the age of 5 years. There are two possible
events: having a birthday party at McDonald’s, and going to a hospital for an injury. The
adults will be either reporting a true memory, meaning that the event actually did happen
in their childhood, or they could be reporting a false memory, in which case the event did
not really happen. Please note that in none of the cases were the adults intentionally
lying. When reporting a false memory, the adults erroneously believed that the event
actually occurred and sincerely “remembered” the event. Your task is to judge whether
each reported memory is true or false. You will complete a Memory Judgment
Questionnaire for each memory report.
When judging the veracity (i.e., true or false) of the memory reports, imagine that you are
a member of a legal investigation team trying to find out if the remembered event
actually occurred or not because a serious crime is suspected to have occurred during the
event. Judge the veracity of each memory report to the best of your ability.
Do you have any questions?
74
Appendix G
Instructions for Group Deliberation
In the next part of the study, you are going to discuss each memory report and make the
veracity judgment as a group, that is, you will try to reach a group consensus. Each group
will randomly select a foreperson who will direct the discussion. After the foreperson is
selected, you will take an initial vote, that is, each of you will state your judgment for the
memory report. You will then discuss the reasons for your judgment and try to reach a
group consensus. You have a maximum of five minutes for each memory report as timed
by the experimenter. When you are done with the discussion (or you have reached the 5
minute limit), take a final vote. Record your final vote on the Post Deliberation
Questionnaire.
Keep in mind that the memory report is either true (the event did happen) or false (the
event did not happen). In none of the cases were the adult intentionally lying. When
reporting a false memory, the adult erroneously believed that the event actually occurred
and sincerely “remembered” the event. Your task is to judge, as a group, whether each
reported memory is true or false.
Remember, when judging the veracity (i.e., true or false) of the memory reports, imagine
that you are engaged in a friendly contest to see who can make the most accurate
judgments. Judge the veracity of each memory report to the best of your ability.
Do you have any questions?
Instructions for Group Deliberation
In the next part of the study, you are going to discuss each memory report and make the
veracity judgment as a group, that is, you will try to reach a group consensus. Each group
will randomly select a foreperson who will direct the discussion. After the foreperson is
selected, you will take an initial vote, that is, each of you will state your judgment for the
memory report. You will then discuss the reasons for your judgment and try to reach a
group consensus. You have a maximum of five minutes for each memory report as timed
by the experimenter. When you are done with the discussion (or you have reached the 5
minute limit), take a final vote. Record your final vote on the Post Deliberation
Questionnaire.
Keep in mind that the memory report is either true (the event did happen) or false (the
event did not happen). In none of the cases were the adult intentionally lying. When
reporting a false memory, the adult erroneously believed that the event actually occurred
and sincerely “remembered” the event. Your task is to judge, as a group, whether each
reported memory is true or false.
75
Remember, when judging the veracity (i.e., true or false) of the memory reports, imagine
that you are a member of a legal investigation team trying to find out if the remembered
event actually occurred or not because a serious crime is suspected to have occurred
during the event. Judge the veracity of each memory report to the best of your ability.
Do you have any questions?
76
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