CURRENT AND COMPLETED RESEARCH PROJECTS
Source memory in adults
Supervisor: Dr. Pascal Boyer
There are two kinds of source memory studies in the literature,
documenting either narrowly construed source monitoring (tagging who
said what) or broader aspects (incidental encoding of properties of the
episodes, such that cued recall is efficient). I am interested in
memory for actual sources of information (i.e., who said it?).
As part of a larger program of research, I am currently testing source
memory for social information. I have been conducting a series of
studies investigating the effect of source credibility, the
relationship between the source and the target, stereotypical
information, etc.
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Number Concepts in Adults
Supervisor: Dr. Pascal Boyer
For most of human history, we may assume as a plausible hypothesis that
the only thing people had to acquire was a small set of digital values
without a numerical system. However, people also engaged in foraging
and social exchange that required specific numerical capacities beyond
the small-number system.
The assumption is that pre-counting mathematical cognition (found in
behaviors such as magnitude estimation, ordinal comparisons) emerged
from activities in which such a capacity carried an evolutionary
significance. In particular, foraging should be the main evolutionary
context for detection of statistical information (mean and variance).
We have conducted several experiments further investigating whether
some aspects of the evolutionary past (magnitude estimation used in
foraging) are still present in modern minds. Specifically, when
presented with two displays, both containing the same number of objects
arranged in different patterns, how do individuals decide which display
contains more objects? The effect of mean, variance, and distance
between "patches" of objects are being investigated.
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Prospective memory in children
Prospective memory refers to a person's memory for actions to be
performed in the future. We are faced with prospective memory tasks,
such as remembering appointments or remembering to buy groceries on the
way home from work, on an everyday basis. In fact, researchers agree
that between 50 and 70% of everyday memory failures in adults are
accounted for by prospective memory failures. Thus, good prospective
memory skills seem to be essential for adults. It is believed that in
children, prospective memory abilities are likely to develop much
earlier than retrospective memory abilities. Even at a young age,
children learn that if they remember to do something they are rewarded,
thus fostering prospective memory development.
Despite its obviously crucial role in everyday life, research on
prospective memory in children is rather limited. To this date, only
about 20 research papers on prospective memory in children have been
published. The proposed study is designed to further investigate
prospective memory in young children.
The current study is designed to investigate the effects of task
interruption, type of instruction, and cue salience on children's
ability to perform simple prospective memory tasks.
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Source memory in children: Effects of object familiarity, source
credibility and information plausibility.
Supervisor: Dr. Pascal Boyer
There are two kinds of developmental studies in the literature,
documenting either narrowly construed source monitoring (tagging who
said what) or broader aspects (incidental encoding of properties of the
episodes, such that cued recall is efficient).
In general, children's source memory abilities start improving around
the age of 6, but younger children have great difficulties in recalling
incidental information. This is interpreted as consequence of more
general problems with either cognitive load (there are too many details
in the episode to recall) or more specifically in terms of integration
of episodic information (linked to fontal lobe function).
Several experiments were designed to investigate the effects of object
familiarity, source credibility and information plausibility on
children's source memory. Data collection is currently underway.
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Detection of animacy and agency in adults and children.
Supervisor: Dr. Pascal Boyer
Research suggests that there is fast identification of living things
based on motion. However, existing literature on animacy and agency
detection shows that these concepts have mostly been studied in terms
of explicit judgments. Our goal is to test the notion of an indirect
measure of motion perception, which would also allow us to test young
children, who may not be capable of making explicit judgments.
In a series of pilot studies, a new protocol has been developed and
validated using several different motion cues (e.g., motion onset,
incoherent motion, etc).
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Eyewitness suggestibility: Effects of repeated interviewing and
logic of opposition instructions.
Data have been collected, analyzed, and presented at AP-LS, March
2004.
Collaborators: Ayde Enriquez & Dr. James M. Wood, University of
Texas, El Paso
Dr. Maria Zaragoza, Kent State University
The negative effects of post-event misinformation can sometimes be
reversed by warning witnesses that they have been misled. We conducted
a study to examine whether such warnings are effective if a witness has
previously retrieved and reported the misleading information. 210
participants watched a videotaped crime (Session 1). Some participants
were afterwards misled about what they had seen. Participants were
later questioned about the video, either with or without a warning that
they had been misled (Sessions 2 and 3). It was predicted that warnings
would largely eliminate the post-event misinformation effect, but not
if participants had previously retrieved and reported the misleading
information.
Results showed that the post-event misinformation effect was
replicated. That is, misled groups were less accurate than non-misled
groups at both follow-up sessions (i.e., Sessions 2 and 3). Contrary to
prior studies, attempts to reverse the post-event misinformation effect
by warnings (i.e., the ''Logic of Opposition'' technique) were
unsuccessful. Warned groups were not significantly different from
non-warned groups. Failure to replicate the logic of opposition effect
was attributed to the study design and materials used in Session1.
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Effects of accuracy feedback on eyewitness suggestibility.
Data have been collected, analyzed, and presented at AP-LS, March
2004.
The manuscript is currently in preparation.
Collaborators: Dr. Deb L. Corey & Dr. James M. Wood, University of
Texas at El Paso.
Participants witnessed a live, staged crime (i.e., the theft of a
wallet). Participants were then interviewed by a
confederate-interviewer who provided information about what other
witnesses had supposedly said (i.e., co-witness information). In some
instances the information was correct, in others incorrect. After
participants responded to the interview questions, the interviewer also
provided accuracy feedback. Results indicated that co-witness
information had an immediate effect on participants' memory accuracy.
In addition, both co-witness information and accuracy feedback had a
delayed effect on participants' memory accuracy. Specifically,
responses to Leading Correct questions were more accurate, and
responses to Leading Incorrect questions were less accurate than
responses to Neutral questions. Findings have implications for forensic
settings, suggesting that eyewitnesses' memory can be impacted when
interviewers provide a) information about what other witnesses said,
and b) feedback to witnesses' statements.