Evolutionary Psychology
human-nature.com/ep - 2004. 2: 108-120
炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉
Original Article
Cheaters Are Looked At Longer and Remembered Better Than
Cooperators in Social Exchange Situations
Dan Chiappe, Department of Psychology, California State University, Long Beach, 1250 Bellflower
Blvd. Long Beach, CA 90840, USA. Email: dchiappe@csulb.edu.
Adam Brown, St. Bonaventure University, St. Bonaventure, New York 14778, USA.
Brian Dow, Jennifer Koontz, Marisela Rodriguez, and Kelly McCulloch, Department of Psychology,
California State University, Long Beach, 1250 Bellflower Blvd. Long Beach, CA 90840, USA.
Abstract: What information is most salient during social exchange? Our studies
assess the relative importance of cheaters and cooperators and whether their
importance is affected by amount of resources involved in the exchange. In
Experiment 1, participants categorized individuals as cheaters, cooperators, or
neither, and rated how important they are to remember using a 7-point scale. In
Experiment 2, participants categorized individuals, and then looked at their photos.
This was followed by tests of face recognition, and memory for social contract status.
Experiment 1 found cheaters were rated more important to remember than
cooperators and more so when a greater amount of resources was involved.
Experiment 2 found cheaters were looked at longer and people had better memory for
their faces and were more likely to remember their social contract status. This
suggests the mind evolved to remember information most pertinent in social contract
situations.
Keywords : Social exchange; social contract theory; memory bias; cheating;
cooperation.
炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉炉
Introduction
Cooperation between individuals for mutual benefit, known as "reciprocal
altruism," is a pervasive feature of social living and has been of crucial importance in
hominid evolution (Cosmides, 1989; Cosmides and Tooby, 1989; 1992; Sugiyama,
Tooby, and Cosmides, 2002; Tooby and DeVore, 1987; Trivers, 1971). Social
exchange, however, can only evolve under certain conditions: Individuals must not be
Cheaters Are Looked At Longer and Remembered Better Than Cooperators in Social Exchange
Situations
indifferent to cheaters (Axelrod, 1984; Cosmides and Tooby, 1989; Dawkins, 1976;
Hamilton, 1964). Research using the Wason selection task has found that people are
adept at identifying people who are in a position to cheat (e.g., Cosmides, 1989;
Cosmides and Tooby, 1992; Gigerenzer and Hug, 1992). Recent neuropsychological
research has found a locus for cheater detection abilities: Patients with bilateral
limbic system damage affecting temporal pole and amygdala are uniquely impaired in
reasoning about social contract versions of the selection task (Stone, Cosmides,
Tooby, Kroll, and Knight, 2002).
In addition to being adept at identifying individuals in a position to cheat,
however, one must also be good at remembering individuals and information
regarding their behavior in previous social exchange situations (Cosmides and Tooby,
1989). But, what information is most important to remember? We test the following
hypotheses:
(1) Cheaters are remembered better than cooperators . This is suggested by two
pieces of evidence: First, it is cheaters who threaten the viability of social exchange
because of the advantages of accepting benefits without paying costs (e.g., Axelrod,
1984; Cosmides and Tooby, 1989, 1992; Dawkins, 1976; Hamilton, 1964). Second,
discovering someone cheated may be more diagnostic of their character than finding
out they cooperated. Successful cheaters have to appear to be trustworthy, so they
likely have to cooperate much of the time.
(2) Cooperators are remembered better than cheaters . People who have
cooperated may be deemed trustworthy, and we may remember them particularly
well so that they can be approached first in future instances of exchange. Indeed, as
Brown and Moore (2000) have argued, due to the problem of subtle cheating, it is
important for people to be good at detecting and remembering individuals with pro-
social motives (see also Brown, Palmetta and Moore, 2003).
(3) Cheaters and cooperators are remembered equally well . Both categories may
be important and worth remembering, though for different reasons. We want to
remember the cheaters because we want to avoid them in the future. We want to
remember the cooperators because they are people that we want to approach first in
future instances of social exchange. Indeed, in Brown and Moore's (2000) study,
performance on altruist-detection and cheater-detection versions of the Wason
selection task were comparable, suggesting people may place equal importance on
detecting and remembering cheaters and cooperators.
Two studies present evidence relevant to these issues (Mealey, Daood, and Krage,
1996; Oda, 1997). Specifically, both of these studies found that the faces of cheaters
were remembered better one week after being exposed to them than were the faces of
those deemed trustworthy. These studies, however, leave some important questions
unanswered. First, they did not examine whether people were more likely to
remember the social contract information of the cheaters. Demonstrating that the
faces of cheaters are more likely to be recognized does not show that people also have
biased access to relevant information about their character. Indeed, according to
Bruce and Young's (1986) model of face perception, recognizing an individual face is
Evolutionary Psychology - ISSN 1474-7049 - Volume 2. 2004.
- 109 -
Cheaters Are Looked At Longer and Remembered Better Than Cooperators in Social Exchange
Situations
a separate and dissociable component from accessing person identity and character
information. Second, the studies do not examine whether the amount of resources
involved in the exchange has an effect on the biased memory for cheaters. It is
possible that differences between cooperators and cheaters emerge only when there is
a substantial amount involved in the exchange and that relatively small amounts do
not lead to any differences in memory for cheaters or cooperators. Third, the studies
did not examine the processes leading to better memory for the faces of cheaters. For
instance, do people spend more time looking at the faces of cheaters than the
cooperators? Fourth, the studies did not examine how soon the bias is evident in
people's memory. They looked at memory one week after exposure, allowing for the
possibility that in relatively short durations, no bias may be evident. Fifth, the studies
did not examine whether people are conscious of the need to remember some
individuals more than others. Is it a product of implicit processing, or is there also
explicit awareness of the relative importance of social contract information? The
present experiments were designed to address each of these questions.
Experiment 1
This study assessed people's explicit judgments of the relative importance of
cheaters and cooperators, and how these judgments are affected by the amount that is
involved in the exchange. Specifically, participants used rating scales to indicate how
important it is to remember individuals they had categorized as cheaters, cooperators,
or neither.
Method
Participants . Forty-nine individuals participated (41 female, 8 male; mean age =
19.74 years, ranging from 18 to 27). In this and the next experiment, all participants
were volunteers from introductory psychology classes at California State University,
Long Beach, and they received extra credit added to their final grade. All were tested
individually.
Stimuli and apparatus . This experiment used eight social contract rules, each
embedded in a scenario providing a context for each rule (see Figure 1 for sample
item) . The rules were of the form "if P then Q", such as "If you borrow money from
John, you must make your payments on time." Along with each rule, participants
received information about different fictional individuals. The information specified
whether the individuals had a) accepted a benefit and failed to pay the cost (cheaters),
b) accepted the benefit and paid the cost (cooperators), or c) the information was
irrelevant to the rule (neither). For the above rule, an example of irrelevant
information would be "This person went to high school with John." For each rule,
information on six individuals was provided: two cheaters, two cooperators, and two
neither, leading to a total of 48 individuals across the eight rules and scenarios.
Evolutionary Psychology - ISSN 1474-7049 - Volume 2. 2004.
- 110 -
Cheaters Are Looked At Longer and Remembered Better Than Cooperators in Social Exchange
Situations
Figure 1
Sample item
John is a very successful businessman. Through his hard work, he has managed to
build a very good life for himself and his family. Though he is well off, he is also
quite generous. He is willing to help out his long-time friends by offering them
loans with interest rates lower than those of local banks. His friends have agreed to
borrow money from John in order to buy cars, homes, and to pay for college tuition
for their children. John's requirement for loaning his friends money is as follows:
If you borrow money from John, you must make your payments on time.
Unfortunately, while some of his friends cooperate with the rule, others have not.
Some decided to borrow money from him without paying it back, while others
promptly make their payments. Your task is to determine, on the basis of the
information given, which of the following individuals are cheaters, which are
cooperators, and which are neither.
Ch1: This person borrowed $2,000 from John and didn't pay him back.
Ch2: This person borrowed $50,000 from John and didn't pay him back.
Co1: This person borrowed $2,000 from John and paid him back.
Co2: This person borrowed $50,000 from John and paid him back.
N: This person went to high school with John.
N: This person was in John's fraternity.
N.B. The full list of items can be obtained from the first author at dchiappe@csulb.edu.
For the cheaters and cooperators, we manipulated the amount or resources involved in
the exchange (See Figure 1). The amounts used were the same for the cheater and
cooperator conditions. In addition, participants were also shown photos of the
individuals. These were color photos of adult males, taken with permission from the
University of Stirling face database, and from the Purdue University face database
(Martinez and Benavente, 1998). To not confound faces with conditions, six different
versions of the experimental program were created, with each photo appearing in
each of the six conditions. Furthermore, two orders were generated for each of these
six versions, so that participants did not always see the faces in the same order. For
each participant, the program also generated a random order of presentation for each
of the eight rules.
Evolutionary Psychology - ISSN 1474-7049 - Volume 2. 2004.
- 111 -
Cheaters Are Looked At Longer and Remembered Better Than Cooperators in Social Exchange
Situations
The experiment was conducted on a Dell00desktop computer, running Super
Lab00 Participants used the "1" key (labeled "CH") to classify cheaters, the "2" key
(labeled "CO") to classify cooperators, and the "3" key (labeled "N") to classify
someone as neither a cheater nor a cooperator on the basis of the information
provided. They used the number keys (from 1 to 7) at the top of the keyboard to
indicate how important it is to remember a given individual.
Procedure . Participants began by reading the instructions for the task, which
required them to categorize individuals as cheaters, cooperators, or neither, on the
basis of the information provided, and then to indicate how important it is to
remember those individuals, using a scale ranging from "1" (not at all important) to
"7" (extremely important). Participants were told that the information we get about
people can suggest that we should remember them. This is because we may have to
interact with them in the future.
Each set of trials began with the scenario presented on the computer screen,
written in black against a white background. The rule appeared in the middle of the
scenario, on a separate line. The scenario remained on screen until participants
pressed the spacebar. Then they received information about six individuals. For each
of the six individuals, trials proceeded as follows: A box (2戮" wide and 3录" long)
appeared in the center of the screen, with a question mark embedded inside. Beneath
it, the information for an individual was shown. The question "Is this person a
cheater, cooperator, or neither? " appeared underneath. Once participants categorized
the individual, a photo of him appeared. It was presented where the box-plus-question
had been. Underneath, the question "How important is it to remember this person?"
appeared, with the seven-point rating scale below. It remained until participants
entered a number. Information for the next individual then followed.
Results
Prior to analyzing the rating scale data, we examined participants' performance in
categorizing the individuals as cheaters, cooperators, or neither. Only participants
with at least 90% accuracy were included in the analyses. Two were excluded,
leaving 47. Table 1 includes the mean rating on the seven-point scale across the
different levels of social contract status.
Table 1
Results for Experiments 1 and 2
Note: Numbers in parentheses are standard deviations. CH = cheater, CO =
cooperator and N = Neither. 1 = less at stake, 2 = more at stake. Means for # of faces
and status recalled are out of a maximum of 8 for CH 1, CH 2. CO 1 and CO 2. They
are out of 16 for the totals.
Evolutionary Psychology - ISSN 1474-7049 - Volume 2. 2004.
- 112 -
Cheaters Are Looked At Longer and Remembered Better Than Cooperators in Social Exchange
Situations
Mean rating on
7-point scale
Mean viewing
time in msec
Mean # faces
recognized
Mean # status
recalled
CH 1
5.67
6132
5.85
3.33
Cheaters
(1.29)
(5271)
(1.58)
(1.68)
CH 2
6.29
6327
5.85
3.42
(1.07)
(5401)
(1.73)
(1.87)
Total
5.98
6306
11.69
6.75
(1.14)
(5297)
(2.91)
(3.20)
CO 1
3.98
5659
5.49
2.76
Cooperators
(1.86)
(5673)
(1.84)
(1.63)
CO 2
4.33
5714
5.48
2.94
(1.81)
(5733)
(1.61)
(1.59)
Total
4.15
5694
10.98
5.69
(1.81)
(5684)
(2.97)
(2.55)
Neither
Total
1.67
3735
9.49
3.38
(0.86)
(3403)
(3.31)
(2.34)
A one-way, repeated-measures ANOVA with social contract status as the repeated
measures factor, revealed a significant difference, F (4, 184) = 144.33, p < .001. Post
hoc, pairwise comparisons with a Bonferroni adjustment revealed that all means were
significantly different from each other. Thus, CH 1, CH 2, CO 1 and CO 2 all
received higher ratings than N, p < .001. Furthermore, CH 2 received higher
importance ratings than CH 1, p < .001; CO 2 received higher ratings than CO 1, p <
.001; both CH 1 and CH 2 received higher ratings than both CO 1 and CO 2, p <
.001.
This was further confirmed with a 2X2 repeated measures ANOVA with status
(cheater vs. cooperator) and amount (lower vs. higher) as the two repeated-measures
factors. There was a main-effect of status, F (1, 46) = 59.83, p < .001. There was also
a main effect of amount, F (1, 46) = 52.52, p < 001 and a significant interaction
Evolutionary Psychology - ISSN 1474-7049 - Volume 2. 2004.
- 113 -
Cheaters Are Looked At Longer and Remembered Better Than Cooperators in Social Exchange
Situations
between status and amount, F (1, 46) = 5.96, p < .05. That is, there was a greater
increase in importance rating for the cheaters (difference = .62 between CH 1 and CH
2) than for the cooperators (difference = .35 between CO 1 and CO 2). Cheaters were
rated more important to remember than cooperators and more so when a greater
amount of resources was involved.
Experiment 2
Experiment 2 examined the amount of time people spend looking at the faces of
cheaters, cooperators and those classified as neither. It also examined whether there
are biases in memory for both the faces of individuals and for information regarding
their character (i.e., whether they were cheaters, cooperators, or neither) and whether
the amount involved in the exchange has an effect on encoding information about
individuals.
Method
Participants . One hundred and twenty eight individuals participated (102 female,
26 male, mean age = 20.4 years, ranging from 18 to 79). All were tested individually,
and were given one hour to complete the task.
Stimuli and apparatus . The eight scenarios, the photos, and information on the
social contract status of individuals from Experiment 1 were used for part one of this
study. The second part of the experiment used 96 photos, 48 from part one, and a
second set of 48 photos, taken from the same face databases. The order in which the
faces were presented was randomized, with one random order per participant.
Both parts of the experiment were conducted on a Dell00desktop computer,
running Super Lab00software. Responses were recorded using a 6-button response
box with millisecond accuracy. From left to right, the first button was red and had no
label. The next two buttons were yellow and labeled "yes" and "no." The remaining
three buttons were green and were labeled "CH," "CO," and "N," representing
cheaters, cooperators, and neither.
Procedure . As in Experiment 1, each of eight sets of trials began with a scenario
presented on the screen, with a rule appearing roughly in the middle of the scenario.
The scenarios remained on screen until participants pressed the red button on the
response box. This was followed by information on six individuals that had to be
categorized according to their social contract status (cheater, cooperator, or neither).
For each of the six individuals, the trials proceeded as follows: A box appeared in the
center of the screen, with a question mark embedded inside. Under the box, the
information for that individual was presented. Beneath the information, the question
"Is this person a cheater, cooperator, or neither? " appeared. Once participants
categorized the individual, a photo of the individual was shown. It was presented
where the box plus question mark had been. The picture remained on the screen until
the participant pressed the red button. Participants were told to look at each photo for
Evolutionary Psychology - ISSN 1474-7049 - Volume 2. 2004.
- 114 -
Cheaters Are Looked At Longer and Remembered Better Than Cooperators in Social Exchange
Situations
as long as they wished. They were also instructed to leave their left index finger on
the red button throughout the first part of the experiment. Once a photo was removed
from the screen, a row of seven asterisk marks appeared on the center of the screen
for 2500 msec, followed by the information for the next individual. Prior to doing the
experimental trials, subjects were given a practice scenario to make sure they knew
what to do in this part of the experiment.
After part one, participants were immediately given a surprise recognition memory
test. They saw photos of adult males, half new and half from part one. The photos
appeared on the center of the screen. For each one, participants had to answer two
questions: (1) Do you recognize this person from part one? And, (2) Was this person
a cheater, cooperator, or neither? These questions appeared, one at a time, beneath
each photo, centered horizontally on the screen. For the first question, they had to
respond by using the yellow buttons labeled "yes" and "no," depending on whether
they recognize the person from the first part. For the second, they had to respond
using the green keys, labeled "CH," "CO," and "N," depending on whether they
remember them as cheaters, cooperators, or neither. If participants did not recognize
the person from part one, they were told to respond "no" to the second question as
well.
Results
As in Experiment 1, only those participants that correctly categorized at least 90%
of the individuals were included in the following analyses. This led to the exclusion
of five participants, leaving a total of 123.
Viewing times for faces
Table 1 lists the mean viewing times for all the faces that were correctly classified
as cheaters, cooperators, or neither. Because the sphericity assumption was violated,
the Greenhouse-Geiser adjustment was used on the viewing times ( 02 (2) = 32.47, p <
.001). A one-way ANOVA revealed significant differences between these three
groups, F (1.62, 197.51) = 61.89, p < .001. Pairwise comparisons using Tukey's HSD
test (critical value = .0588) found that cheaters were looked at longer than
cooperators ( p < .05), cheaters were looked at longer than those categorized as neither
( p < .05), and the cooperators were also looked at longer than those categorized as
neither ( p < .05).
To examine whether the amount involved in the exchange affected viewing time,
we carried out a repeated measures ANOVA, with social contract status (cheater vs.
cooperator) and amount (less vs. more) as repeated measures factors. There was a
significant effect of social contract status, with viewing times greater for cheaters, F
(1, 122) = 15.57, p < .001. Although the descriptive statistics revealed longer viewing
times when a higher amount was involved in the exchange, this was not significant, F
(1, 122) = .72, p = .397. There was also no interaction, F (1, 122) = .18, p = .669.
Evolutionary Psychology - ISSN 1474-7049 - Volume 2. 2004.
- 115 -
Cheaters Are Looked At Longer and Remembered Better Than Cooperators in Social Exchange
Situations
Face recognition
Table 1 lists the mean number of faces recognized for cheaters, cooperators, and
those classified as neither. A one-way repeated measures ANOVA was carried out to
examine overall differences in face recognition. Because the sphericity assumption
was violated, the Greenhouse-Geiser adjustment was used ( 02 (2) = 13.46, p = .001).
The ANOVA revealed significant differences between these three groups, F (1.81,
220.76) = 34.43, p < .001. Pairwise comparisons using Tukey's HSD test (critical
value = .676) found that the faces of cheaters were remembered better than the
cooperators ( p < .05), the faces of cheaters were remembered better than those
categorized as neither ( p < .05), and the faces of cooperators were also remembered
better than those categorized as neither ( p < .05).
To examine whether the amount involved had an effect on the likelihood of faces
being recognized, we carried out a repeated measures ANOVA, with social contract
status (cheater vs. cooperator) and amount (less vs. more) as the two repeated
measures factors. The results revealed a significant effect of social contract status,
with cheaters being more likely to be remembered, F (1, 122) = 10.63, p < .001.
Although the descriptive statistics revealed greater recognition when more was at
stake in the exchange compared to when less was involved, this failed to be
statistically significant, F (1, 122) = 0.005, p = .943. There was also no interaction
between social contract status and amount involved in the exchange, F (1, 122) = .00,
p = 1.00.
Memory for social contract status
Table 2 lists the mean number of individuals for whom participants could correctly
recall the social contract status (i.e., cheater, cooperator or neither). A one-way
repeated measures ANOVA was carried out to examine overall differences in
memory for the social contract status. The sphericity assumption was satisfied ( 02 (2)
= 3.54, p = .171). The results revealed significant differences between the three
groups, F (2, 244) = 78.43, p < .001. Pairwise comparisons using Tukey's HSD test
(critical value = .653) found that the social contract status was more likely to be
remembered for cheaters than cooperators ( p < .05), more likely to be remembered
for cheaters than those categorized as neither ( p < .05), and more likely to be
remembered for cooperators than for those categorized as neither ( p < .05).
To determine whether the amount involved had an effect on the likelihood of the
social contract status being remembered, a repeated-measures ANOVA was done,
with social contract status (cheater vs. cooperator) and amount (less vs. more) as the
two repeated measures factors. The results revealed a significant effect of status, with
cheaters more likely to have their social contract status remembered, F (1, 122) =
15.15, p < .001. Though the descriptive statistics revealed greater likelihood of
remembering social contract status when more resources were involved, this was not
Evolutionary Psychology - ISSN 1474-7049 - Volume 2. 2004.
- 116 -
Cheaters Are Looked At Longer and Remembered Better Than Cooperators in Social Exchange
Situations
significant, F (1, 122) = .1.29, p = .259. There was also no interaction between status
and amount of resources involved, F (1, 122) = 0.13, p = .719.
General Discussion
These studies examined the salience of information in social contract situations.
We tested three claims about the relative importance of cheaters and cooperators: (1)
Cheaters are more important to remember than cooperators, (2) Cooperators are more
important to remember than cheaters, and (3) Cheaters and cooperators are equally
important to remember. Our results are most consistent with the first. Experiment 1
found people rated cheaters more important to remember than cooperators, though
both were rated higher than those categorized as neither. Experiment 2 found cheaters
were looked at longer than cooperators, though both were looked at longer than those
classified as neither. People also had better memory for faces of cheaters than
cooperators, and were more likely to remember social contract information for
cheaters.
Why should cheaters be particularly salient? One reason is because cheaters
threaten the very viability of social exchange (e.g., Cosmides, 1989; Cosmides and
Tooby, 1992; Gigerenzer and Hug, 1992). Unless steps are taken to identify and
remember individuals that accept benefits and fail to pay costs, cheaters would outreproduce
cooperators. Furthermore, instances of cheating may carry greater
information value. If evolution works to improve the efficiency of cognitive
mechanisms, we would expect that it would produce a cognitive system that is
particularly sensitive to information that has the greatest diagnostics value. In this
case, it should be most sensitive to information providing cues about a person's
character. Everything else being equal, knowing that a person cooperated may not tell
us much about their character. Knowing that they cheated would be more relevant.
This is because cheaters have to give the appearance of being trustworthy and thus
they may have to cooperate much of the time.
However, our results also provide some support for the view that it is important to
remember cooperators. Cooperators were looked at longer and remembered better
than those judged irrelevant to the social contract situation. This suggests that people
also regard as important individuals displaying pro-social behavior (Brown and
Moore, 2000). This is important because individuals need to know whom to approach
in future instances of exchange, not just which individuals to avoid. Of course, it may
also be important to rely on information from other people in the form of gossip, to
avoid the problem that even cheaters often have to cooperate (Emler, 1990, 1992).
The present studies also found that people can make conscious judgments of the
relative importance of remembering cheaters and cooperators. This was revealed in
Experiment 1, where explicit judgments of importance were assessed. This suggests
people can strategically implement encoding strategies that increase the likelihood of
remembering different individuals. For instance, by knowing that they want to
remember the cheaters, people can decide to spend more time looking at their faces
Evolutionary Psychology - ISSN 1474-7049 - Volume 2. 2004.
- 117 -
Cheaters Are Looked At Longer and Remembered Better Than Cooperators in Social Exchange
Situations
relative to individuals with a different social contract status. This is what we found in
Experiment 2.
Our studies also examined whether the amount of resources involved in the
exchange has an effect on the relative importance of remembering cheaters and
cooperators. One would expect that any differences in importance between the two
should be particularly evident when there is more to lose or gain in an exchange.
When trivial amounts are involved, the relative difference in importance between
cheaters and cooperators may be negligible. The amount involved in the exchange
could also affect the actions that a person takes in dealing with cheaters. As Cosmides
and Tooby (1989) put it, "When you believe that I have cheated you in a major way,
there should be a flood of memories about your past history with me: You must
decide whether it is worth your while to continue our relationship" (p. 63). Thus, do
you give a person another chance, or do you exclude them outright from all future
exchange? The extent of the infraction likely plays an important role in this regard.
The first study found that people gave higher important-to-remember ratings when
a greater amount was involved. However, the results of the second experiment failed
to find an effect of amount. Thus, people's conscious intentions did not turn into
longer viewing times, and did not turn into a greater likelihood of remembering the
individuals. Though the descriptive statistics were in that direction, the results were
not significant. This could be due to the high amounts of variance observed in the
viewing times. High variance can have the effect of eliminating any differences
observed between experimental conditions. By contrast, the data in the first
experiment were obtained using a 7-point rating scale. By its very nature, this
constrains much of the variance, making it more likely that an effect will be
significant. At any rate, further research will be required to address this issue.
Another interesting discovery of the present study has to do with how quickly the
effects on memory are evident. Previous studies have found differences in memory
between cheaters and cooperators with a delay of a week between first exposure to
the faces and subsequent attempts at recognition (Mealey, Daood, and Krage, 1996;
Oda, 1997). These studies, however, did not examine whether those biases are
evident after only a short delay. Indeed, one might expect that in the short run, no bias
would be evident because the individuals would be relatively fresh in memory.
Interestingly, however, a bias in remembering the cheaters was evident shortly after
the individuals were first seen. Thus, cheaters stand out right away, more so than do
people exhibiting pro-social behavior. Future research will have to determine whether
differences between cheaters and cooperators get larger with time or remain constant.
Importantly, the memory bias was evident not just in terms of face recognition, but
also with respect to the social contract status. The studies by Mealey, Daood, and
Krage (1996) and Oda (1997) found biased face recognition for cheaters, but did not
examine whether there are differences in the likelihood of remembering that the
cheaters were cheaters compared to remembering that the cooperators were
cooperators. As noted above, however, one must not only be able to recognize many
different individuals, one must also be able to recall how those individuals behaved in
Evolutionary Psychology - ISSN 1474-7049 - Volume 2. 2004.
- 118 -
Cheaters Are Looked At Longer and Remembered Better Than Cooperators in Social Exchange
Situations
social contract situations. This is crucial for deciding whether or not to channel future
resources to an individual. Our studies suggest that biases in memory also extend to
the information regarding the individual's character.
To conclude, though much research has shown people are good at identifying
potential violators of social contract rules, the present study shows that people are
adept at remembering the information that carries the greatest diagnostic value in
social exchange. People are particularly good at remembering the faces of cheaters,
and that these individuals violated social contract rules, compared to other social
contract information. Moreover, our results suggest that this may be accomplished at
least in part by spending a greater amount of time looking at the faces of these
individuals.
Received 15 March, 2004, Revision received 17 June, 2004, Accepted 27 June,
2004.
References
Axelrod, R. (1984). The Evolution of Cooperation . New York: Basic Books.
Brown, W. M. and Moore, C. (2000). Is prospective altruist-detection an evolved
solution to the adaptive problem of subtle cheating in cooperative ventures?
Supportive evidence using the Wason selection task. Evolution and Human
Behavior, 21 : 25-37.
Brown, W. M. Palameta, B., and Moore, C. (2003). Are there nonverbal cues to
commitment? An exploratory study using the zero-acquaintance video
presentation paradigm. Evolutionary Psychology, 1 : 42-69.
Bruce, V. and Young, A. (1986) . Understanding face recognition. British Journal of
Psychology, 77 : 305-327.
Cosmides, L. (1989). The logic of social exchange: Has natural selection shaped how
humans reason? Studies with the Wason selection task. Cognition, 31 : 187-276.
Cosmides, L. and Tooby, J. (1989). Evolutionary psychology and the generation of
culture, Part II. Ethology and Sociobiology, 10 : 51-97.
Cosmides, L. and Tooby, J. (1992). Cognitive adaptations for social exchange. In
Barkow, J., Cosmides, L., and Tooby, J. (Eds.), The Adapted Mind (pp. 163-228).
New York: Oxford.
Emler, N. (1990). A social psychology of reputations. European Journal of Social
Psychology, 1 : 171-193.
Emler, N. (1992). The truth about gossip. Social Psychology Newsletter, 27 : 23-37.
Gigerenzer, G. and Hug, K. (1992). Domain-specific reasoning: Social contracts,
cheating, and perspective change. Cognition, 43 : 127-171.
Hamilton, W. D. (1964). The genetical theory of social behavior. Journal of
Theoretical Biology, 7 : 1-52.
Martinez, A., and Benavente, R. (1998). The AR Face Database . CVC Technical
Report #24, June 1998.
Evolutionary Psychology - ISSN 1474-7049 - Volume 2. 2004.
- 119 -
Cheaters Are Looked At Longer and Remembered Better Than Cooperators in Social Exchange
Situations
Mealey, L., Daood, C., and Krage, M. (1996). Enhanced memory for faces of
cheaters. Ethology and Sociobiology, 17 : 119-128.
Stone, V., Cosmides, L., Tooby, J., Kroll, N., and Knight, R. (2002). Selective
impairment of reasoning about social exchange in a patient with bilateral limbic
system damage. Proceedings of the National Academy of Sciences, 99 : 11531-
11535.
Sugiyama, L. Tooby, J., and Cosmides, L. (2002). Cross-cultural evidence of
cognitive adaptations for social exchange among the Shiwiar of Ecuadorian
Amazonia. Proceedings of the National Academy of Sciences, 99 , 11537-11542.
Oda, R. (1997). Biased Face Recognition in the Prisoner's Dilemma Game.
Evolution and Human Behavior, 18 : 309-315.
Tooby, J. and DeVore, I. (1987). The reconstruction of hominid behavioral evolution
through strategic modeling. In Kinzey, W. G. (Ed.), Primate Models for the Origin
of Human Behavior (pp. 183-237). New York: SUNY Press.
Trivers, R.L. (1971). The evolution of reciprocal altruism. Quarterly Review of
Biology, 46 : 35-57.
Evolutionary Psychology - ISSN 1474-7049 - Volume 2. 2004.
- 120 -
search
