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Accepted for publication in Acta Psychologica

Eyes keep watch over you! Competition enhances joint attention in females

Francesca Ciardo1, Paola Ricciardelli2,3, Luisa Lugli4, Sandro Rubichi1, Cristina Iani1

(1) Department of Communication and Economics, University of Modena and Reggio Emilia

Viale Allegri, 9, 42121 Reggio Emilia, Italy

(2) Department of Psychology, University of Milano-Bicocca,

Edificio U6, Piazza dell’Ateneo Nuovo 1, 20126 Milan, Italy

(3) Milan Centre for Neuroscience, Piazza dell’Ateneo Nuovo 1, 20126, Milan, Italy

(4) Department of Philosophy and Communication, University of Bologna, University of Bologna,

Via A. Gardino 23, 40122 Bologna, Italy

Word count (main text): 6287

References: 51

Address for Correspondence:

Francesca Ciardo or Cristina Iani

Department of Communication and Economics, University of Modena and Reggio Emilia

Viale Allegri, 9, 42121 Reggio Emilia, Italy

E-mail: [email protected]; [email protected]

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ABSTRACT

The present study investigated if the gaze-cuing effect (i.e., the tendency for observers to respond

faster to targets in locations that were cued by others’ gaze direction than to not-cued targets) is

modulated by the type of relationship (i.e., cooperative or competitive) established during a

previous interaction with a cuing face. In two experiments, participants played a series of single-

shot games of a modified version of the two-choice Prisoner's Dilemma against eight simulated

contenders. They were shown a fictive feedback indicating if the opponents chose to cooperate or

compete with them. Opponents’ faces were then used as stimuli in a standard gaze-cuing task. In

Experiment 1 females classified as average in competitiveness were tested, while in Experiment 2

females classified as high and low in competitiveness were tested. We found that only in females

classified as low and average in competitiveness the gaze-cuing effect for competitive contenders

was greater than for cooperative contenders. These findings suggest that competitive opponents

represent a relevant source of information within the social environment and female observers with

low and average levels of competition cannot prevent from keeping their eyes over them.

Keywords: Joint attention; Social interaction; Competition; Cooperation; Prisoner’s Dilemma

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1. INTRODUCTION

Orienting attention in the same direction where other individuals are looking at, known as

joint attention, is a foundational ability guiding social interactions and communication (Langton,

Watt, & Bruce, 2000). The gaze-mediated orienting of attention allows the observer to infer other

people’s mental states (i.e., the focus of their attention; e.g. Baron-Cohen, 1995), and to understand

and predict their future actions (e.g., Pierno et al., 2006; Innocenti, De Stefani, Bernardi, Campione,

& Gentilucci, 2012).

Even though there are several indications of the automatic and reflexive nature of the mecha-

nisms underlying the gaze-mediated orienting of attention (e.g., Galfano et al., 2012; Hayward &

Ristic, 2013; but see Frischen, Bayliss, & Tipper, 2007 for a review), recent studies suggested that

joint attention orienting may not be purely bottom-up driven, but it is rather influenced by top-down

processes that interpret the averted gaze based on its relevance for the task (e.g., Ricciardelli,

Carcagno, Vallar, & Bricolo, 2013), and in comparison to other stimuli in the environment (e.g.,

Green, Mooshagian, Kaplan, Zaidel, & Iacoboni, 2009; Ristic & Kingstone, 2005).

Furthermore, there are recent reports that joint attention is influenced by implicit and explicit

social information associated to the seen person, such as age (Ciardo, Marino, Actis-Grosso, Ros-

setti, & Ricciardelli, 2014), facial emotional expression (e.g., Bonifacci, Ricciardelli, Lugli & Pelli-

cano, 2008), gender (Olhsen, van Zoest, & van Zugt, 2013), race (Pavan, Dalmaso, Galfano, &

Castelli, 2011), social status (e.g., Dalmaso, Pavan, Castelli, & Galfano, 2012) and political affilia-

tion (Liuzza et al., 2011). For instance, Liuzza and colleagues (2011), using an oculomotor task, re-

ported that political affiliation enhanced joint attention for in-group voters while it inhibited it for

out-group voters. Similar results have been reported by Pavan et al. (2011) who investigated the im-

pact of racial group membership on covert orienting of joint attention and reported that White par-

ticipants selectively shifted their attention in response to the averted gaze of own-race individuals

only. Therefore, person categorization seems to regulate joint attention.

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The way we perceive and categorize others may depend on the type of relationship we have

with them. Group membership acts as a strong categorization cue. There are indications that the

need to cooperate or to compete leads to in-group/out-group differentiations, with individuals per-

ceiving themselves as part of the same social group when they need to cooperate with each other.

On the contrary, when the others represent an obstacle toward the attainment of a goal, they are

more likely perceived as out-group members (e.g., Rabbie & Horwitz, 1969). In general, competi-

tive interactions have been shown to increase perceived intergroup and interpersonal differences

(e.g., Toma, Yzerbyt, & Corneille, 2010) and to disrupt the emergence of shared task representa-

tions in joint action (e.g., Iani, Anelli, Nicoletti, Arcuri, & Rubichi, 2010). Interestingly, the effects

of competition may be long lasting and transfer from one task to a subsequent one (e.g., Iani, Anelli,

Nicoletti, & Rubichi, 2014; Sassenberg, Moskowitz, Jacoby, & Hansen, 2007).

To note, competitors are a special kind of out-group members as the achievement of their

goals often coincides with the impossibility to reach ours. For these reasons, in competitive situa-

tions it appears fundamental for the observer to monitor their progress toward their goals (Poortvliet

& Darnon, 2010). Evidence indicates that social interactions characterized by cooperation differ-

ently affect individual cognitive processes, such as attention, face recognition and memory, with

faces of non-cooperative individuals attracting more automatic attention (e.g., Vanneste, Verplaet-

seb, Van Hiela, & Braeckmanc, 2007) and being memorized more accurately (e.g., Chiappe et al.,

2004; Mealy, Daood, & Krage, 1996; Oda, 1997; Yamagishi, Tanida, Mashima, Shimoma, &

Kanazawa, 2003) than those of cooperative individuals.

Given the above considerations, the present study aimed to better clarify how social informa-

tion, in particular person categorization, influences joint attention. Since previous studies indicated

that females show stronger gaze cuing effects (Bayliss, Di Pellegrino, & Tipper, 2005) and higher

sensibility to social cues (e.g., Deaner, Shepherd, & Platt, 2007; see Geary, 2010 for a review) than

males, to avoid additional sources of variability in the data, only female participants were included

in the present study (see Bayliss, Schuch, & Tipper, 2010). Specifically, we run two experiments to 4


investigate whether the gaze-cuing effect is modulated by the cooperative and competitive behavior

associated to a cuing face during a prior interaction. In Experiment 1, we included only individuals

classified as average in competition, as measured through the Competitiveness Index Questionnaire

developed by Smither and Houston (1992). In Experiment 2, participants rated as high and low in

competitiveness were included.

In both experiments, we employed a standard gaze-cuing paradigm (Driver et al., 1999) and

manipulated the relationship between the participant and the cuing faces via a preliminary learning

phase in which participants associated faces of simulated opponents with a cooperative or competi-

tive behavior. In this phase, participants were required to play a series of single-shot games of a

modified version of the two-choice Prisoner's Dilemma against eight simulated contenders. After

participants had indicated their response at the social dilemma game, they were shown a fictive

feedback indicating if the opponents chose to cooperate or compete with them. Opponents’ faces

were then used as stimuli in the subsequent standard gaze-cuing task.

2. EXPERIMENT 1

The present experiment aimed at investigating whether the gaze-cuing effect (i.e., the ten-

dency for observers to respond faster to targets in locations that were cued by others’ gaze direction

than to not-cued targets) is modulated by the type of relationship (i.e., cooperative or competitive)

established during a previous interaction with a cuing face. Since individuals’ competitiveness lev-

els may affect how situations and others are perceived (e.g., Houston, Kinnie, Lupo, Terry, & Ho,

2000), in this experiment we included only individuals classified as average in competition.

We hypothesized that cooperative and competitive interactions between the observer and the seen

face differently affect joint attention. Specifically, if a cooperative behavior associated with the seen

face influences joint attention by increasing group membership, as suggested by the results of

previous studies on joint attention (e.g., Liuzza et al., 2011; Pavan et al., 2011), then the gaze-cuing

effect should be magnified for cooperative individuals which tend to be classified as in-group 5


members. On the contrary, the gaze-cuing effect should not be evident for faces associated with a

competitive behavior, since they are classified as out-group members (Rabbie & Horwitz, 1969).

Alternatively, if competition affects joint attention by increasing the salience of some averted gazes

more than others, then the gaze-cuing effect should be magnified for faces associated with

competitive outcomes, since they represent a privileged source of information in the environment.

In both cases, we expected these modulations to affect longer response times since information

about the prior interaction with the cuing face has to be retrieved from memory. To this aim,

response times were analyzed by means of the bin distributional analysis (e.g., Ratcliff, 1979). The

distributional analysis of reaction times (RTs) consists in rank ordering individual RTs as a function

of the experimental conditions and in dividing them into a number of intervals or bins so that it can

be seen whether a variable influences different portions of the RT distribution (e.g., De Jong, Liang,

& Lauber, 1994; see Balota, & Yap, 2011 for a review). In the present study we used this technique

to assess the time course of the social manipulation (i.e., the type of interaction) on the gaze-cuing

effect. Specifically, if the modulation of the gaze-cuing effect is due to the retrieval from memory

of the social information, then the difference between competitive and cooperative relations on the

gaze-cuing effect should emerge for slower responses (i.e., the longer intervals of the distribution).

2.1 METHODS

2.1.1 Participants

Twenty-four female undergraduate students (1 left-handed; M = 21.08 years, SD = 2.21 years)

from the University of Modena and Reggio Emilia received course credit to participate to the study.

All had normal or corrected-to normal vision and were naïve as to the purpose of the experiment.

The study was conducted in accordance with the ethical standards laid down in the Declaration of

Helsinki, and fulfilled the ethical standard procedure recommended by the Italian Association of

Psychology (AIP). Written consent was obtained for all of them and they were debriefed about the

study at the end of the experiment. 6


They were selected from a larger sample (n=95) based on their scores at the Competitiveness

Index (CI) questionnaire (Smither & Houston, 1992; Houston et al., 2000). To be included in the

study, they had to score in the average competitiveness range (4-12). Mean scores for the partici-

pants included in the study were 8.17 (SD = 2.55).

Apparatus and Stimuli

Each participant was tested in a single session, lasting about 45 minutes. All tasks were

performed on a computer. Participants sat approximately 55 cm from a 17’’ CRT screen driven by a

700 MHz processor computer. Stimulus presentation and data collection were controlled by a PC

running E-Prime version 2.0 software system (Psychology Software Tools, Inc).

Simulation of social interactions was achieved using a modified version of the two-choice

Prisoner’s Dilemma game (i.e., Poundstone, 1992), that provides one of the most widely used way

to induce cooperative and competitive outcomes (Chan & Ybarra, 2002; Vonk, 1998). The dilemma

(translated here from Italian) was presented as follows: "You and another student have copied the

final test of the Psychology class. The Professor has noticed that your tests are identical and he

convenes separately both of you into his office with no means of speaking to or exchanging

messages between the two of you. The Professor tells you that: a) If both of you confess that you

have copied the test, then you will have to wait for 6 sessions before taking the test again; b) If

neither of you confesses, then both of you will have to wait for 1 session before taking the test

again; c) If only one of you confesses, he/she will pass the exam without taking the test again, while

the other has to wait for 7 sessions before taking the test again”.

Stimuli used in the social dilemma, in the memory test and in the gaze-cuing task were

grayscale photographs (7.98° × 15.76°) depicting 8 young adults (4 females and 4 males) bearing a

neutral expression. All photographs were taken from the Productive Aging Lab Face Database

(Minear & Park, 2004). In the gaze-cuing task, for each photograph, gaze direction was manipulated

using Adobe Photoshop so that gaze could be averted 0.65° to the left or to the right.

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2.1.2 Procedure

At the beginning of the experimental session, participants were told that they would take part

in three different and independent tasks concerning social judgment, memory and attention. This

general introduction allowed us to administer the social dilemma and social interaction rating

procedures before the gaze-cuing task. Participants were first required to play a series of single-shot

games of the modified version of the two-choice Prisoner's Dilemma against eight simulated

contenders. They were presented with photographs depicting the 8 young adults (i.e., opponents)

bearing a neutral expression and a straight gaze. For each photograph, participants were required to

imagine of being in the situation described by the social scenario and to indicate if they wanted to

cooperate or compete with the opponent. Participants were provided with the cover story that the

day before the opponents performed the same task seeing the participant student-id photograph. For

each game, participants were shown the text of the social dilemma, their possible choices and the

associated outcomes, the photograph of their opponent and a fictive name associated with the face.

Half of the participants pressed the B-key on a standard keyboard if they decided to confess and the

H-key if they decided not to confess. The other half experienced the opposite mapping. After

participants had indicated their choice, they were shown a fictive feedback indicating the

opponent’s choice. The order of presentation of the 8 photographs was randomized and each photo

remained visible until each game ended.

Instructions explicitly defined the decision to confess as a competitive behavior and the

choice to deny as a cooperative behavior. Instructions required participants to associate each

opponent’s face to his/her behavior (cooperative or competitive). To facilitate the retrieval of the

information about the opponent’s face and his/her behavior, two different versions of the social

dilemma procedure were created. In version 1, female opponents always exhibited a cooperative

behavior, while male opponents exhibited a competitive behavior. In version 2 the association

gender-behavior was reversed. Half of the participants were administered version 1, while the other

half were administered version 2. 8


To verify whether participants memorized the association between the opponent’s face and

his/her behavior, at the end of the social dilemma game they were administered a true/false test in

which each of the 8 faces was associated with a statement that could be either true or false (e.g.,:

He/she chose to cooperate with/compete against you). For each face, four statements (two true and

two false) were presented for a total of 32 trials. The order of presentation of the trials was

randomized. Participants responded by pressing the V-key on the keyboard if the statement was

true, and the F-key if the statement was false. If the participant gave a wrong answer, the whole test

was administered again until participant’s accuracy reached 100%.

Once participants successfully completed the true/false questionnaire, they were required to

rate the social interaction with each opponent using a 6-point bipolar semantic differential scale on

the following dimensions (Iani et al., 2011): easy vs. difficult (1 = difficult, 6 = easy), pleasant vs.

unpleasant (1 = unpleasant, 6 = pleasant), positive vs. negative (1 = negative, 6 = positive), non-

cooperative vs. highly-cooperative (1 = non-cooperative, 6 = highly-cooperative) and non-

competitive vs. highly-competitive (1 = non-competitive, 6 = highly-competitive). Immediately

after, they took part in a gaze-cuing task in which the same 8 faces presented in the social dilemma

task were used as cuing faces.

Figure 1. Illustration of the gaze-cuing procedure depicting examples of stimuli (not drawn to scale) and sequence of events for a spatially congruent trial (top) and a spatially incongruent trial

(bottom).

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Each trial began with the presentation of a white fixation cross (0.83°) in the center of a black

screen for 900 ms (fixation frame), followed by a central face with straight gaze (face frame). After

900 ms, the same face appeared with averted gaze (cue frame). After 200 ms, a white target letter (L

or T, 0.83°) appeared 10.8° to the left or right of the center of the screen in one of two possible

locations that could be spatially congruent or incongruent with gaze direction. The target frame

remained visible until a response was provided (see Dalmaso et al., 2012, for a similar gaze-cuing

procedure). Gaze direction was uninformative as regards target location. Participants were explicitly

instructed to respond according to the letter identity while ignoring the distracting face and to

maintain fixation at the center of the screen. We chose a 200-ms stimulus onset asynchrony (SOA)

between gaze-cue and target because this interval is long enough to allow the encoding of the gaze

and, at the same time, it is short enough to automatically cue attention (see Frischen, Bayliss, &

Tipper, 2007 for a review). Furthermore, this SOA has also been used in previous studies assessing

the modulation of gaze-cuing by social factors (Dalmaso et al., 2012; Pavan et al., 2011) hence we

chose it to facilitate comparisons.

Half of the participants were instructed to press the D-key on the keyboard if the target was an

‘L’, and the K-key if the target was a ‘T’. The remaining participants responded using the opposite

stimulus-response mapping. Instructions emphasized both response speed and accuracy. No

feedback was provided.

There were 64 trials for each combination of congruency between gaze direction and target

location (congruent vs. incongruent) and social relation with the previous social dilemma’s

opponent who now served as distracter. A total of 256 trials were randomly presented and divided

into two equal blocks of 128 trials each. A short rest was allowed between blocks. A practice

session of 16 trials was given prior to the beginning of the first block. At the end of the

experimental session, participants were asked if they had guessed the main aim of the experiment.

All participants answered “no” and claimed that they believed to the information provided by the

experimenter at the beginning of the session.10


2.2 RESULTS AND DISCUSSION

2.2.1 Social dilemma

Overall, 61.2% of the participants decided to cooperate. A one sample t test showed that this

percentage marginally differed from the chance level of 50%, t(23) = 1.98, p = .06. Since both male

and female photos were used, we computed the percentage of participants who chose to cooperate

or compete as a function of the opponent’s gender. Cooperative choices did not differ from the

chance level both when the face belonged to a female (61.5%, t(23) = 1.85, p = .08) or it belonged

to a male (60.4%, t(23) = 1.59, p = .13). This result indicates that the gender of the face did not

affect participants’ performance at the social dilemma.

2.2.2 Subjective Ratings

T tests for independent samples were used to compare the subjective ratings of the social

dilemma situation involving cooperative and competitive opponents. Scores significantly differed

between cooperative and competitive opponents for all dimensions (all ps< .001) (see Table 1).

The finding that when the opponent displayed a competitive behavior the situation was judged

as more competitive and as less cooperative than when he/she displayed a cooperative behavior

confirmed that our manipulation was effective.

Social Relationship

Cooperative Competitivet p-value

Cooperative 5.2 (0.7) 1.8 (0.7) 12.3 < .001

Competitive 2.2 (1.1) 4.9 (1.0) -6.7 < .001

Easy 4.8 (0.9) 2.7 (0.8) 8.7 < .001

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Pleasant 4.7 (0.7) 2.1 (0.7) 10.0 < .001

Positive 4.9 (0.9) 2.0 (0.7) 10.0 < .001

Table 1. Experiment 1: Mean subjective ratings (and standard deviations) of the social interaction with the opponent as a function of the opponent’s behavior (cooperative vs. competitive).

2.2.3 Gaze-cuing Responses

Practice trials, errors (2.9% of the total trials) and trials with RTs faster than 150 ms or slower

than 3000 ms (0.2% of the total trials) were excluded from the analyses.

Correct mean RTs were entered into a repeated-measures analysis of variance (ANOVA) with

cue-target spatial congruency (congruent vs. incongruent) and social relationship (cooperative vs.

competitive) as within-participant factors and version of the social dilemma (version 1: cooperative

female opponents and competitive male opponents; version 2: cooperative male opponents and

competitive female opponents) as between-participants factor. When necessary, comparisons were

performed using paired samples t tests and by correcting the p value for the number of comparisons

(Bonferroni correction).

The analysis revealed a significant main effect of cue-target spatial congruency, F(1,22) =

14.67, p = .001, ηp2 = .40, indicating that participants were faster to identify the target when it

appeared in the gazed-at location (i.e., congruent trials, M = 586 ms, SE = 16.81 ms, 95% CI from

551 to 621 ms) as compared to when it appeared in the opposite location (i.e., incongruent trials, M

= 603 ms, SE = 17.43, 95% CI from 567 to 639 ms). The main effect of social relationship did not

reach significance, F < 1, but it interacted with cue-target spatial congruency, F(1,22) = 8.98, p

< .05, ηp2 = .29. Post-hoc showed that the difference between congruent and incongruent trials (i.e.,

gaze-cuing effect) was significant (26 ms, 95% CI from 15 to 38 ms) for competitive opponents

(581 vs. 607 ms, t(23) = 4.64, p Bonferroni corrected < .001), but did not reach significance (8 ms, 95% CI

12


from -2 to 19 ms) for cooperative opponents (591 vs. 599 ms, t(23) = 1.74, p Bonferroni corrected = .38)

(see Figure 2). Neither congruent nor incongruent trials differ across the two social relationship

conditions (ps Bonferroni corrected > .33). The main effect of version did not reach significance, F(1,22) =

2.84, p =.11, and did not interact with the other factors, all Fs < 1.

Figure 2. Mean RTs (± s.e.m.) in ms, collapsed across versions, for spatially congruent (grey) and incongruent (black) trials as a function of the social relation with the cuing face for Experiment 1

(panel a) and Experiment 2 (panel b). Asterisks denote significant differences.

In order to evaluate the time course of the influence of the social manipulation on the gaze-

cuing effect, a distributional analysis of RTs was performed (Ratcliff, 1979). To have enough

observations in each bin, we chose to divide the RT distribution in quartiles. Thus, individual

correct RTs for each condition were rank ordered and divided into four bins. Mean RTs for each bin

were then entered into a repeated-measures analysis of variance (ANOVA) with cue-target spatial

congruency (congruent vs. incongruent), social relationship (cooperative vs. competitive) and bin (1

to 4) as within-participant factors.

Besides the effects and interactions already discussed in the overall analysis, the analysis

showed a main effect of bin, F(3,69) = 184.78, p < .001, ηp2 = .89, that reflected RTs increasing with

bin. The two-way interaction between bin and cue-target spatial congruency was significant,

F(3,69) = 3.43, p < .05, ηp2 = .13, as was the three-way interaction between bin, cue-target spatial

congruency, and social relationship, F(3,69) = 3.74, p < .05, ηp2 = .14 (see Figure 3). Post-hoc

showed that when the distracter face belonged to a previously cooperative opponent the difference

13


between congruent and incongruent trials was significant only in the first bin, t(23) = 3.30, p Bonferroni

corrected = .02 (13, 8, 4, 10 ms from bin 1 to bin 4). Differently, when the face belonged to a

previously competitive opponent the difference was significant in the first bin, t(23) = 3.67, p Bonferroni

corrected = .01, and in the last bin, t(23) = 3.18, p Bonferroni corrected = .03. The difference was marginally

significant in the second, t(23) = 2.93, p Bonferroni corrected = . 06, and third bin, t(23) = 2.85, p Bonferroni

corrected = . 07 (17, 12, 14, 60 ms from bin 1 to bin 4).

1 2 3 4Bin

0

10

20

30

40

50

60

70

GC

E (m

s)

Figure 3. Experiment 1: Magnitude of the gaze-cuing effect (± s.e.m.) in ms for the competitive (dotted line) and cooperative (solid line) social relation conditions as a function of bin.

Our results indicate that the type of relationship (i.e., cooperative or competitive) established

during a previous interaction with a cuing face can modulate the gaze-cuing effect in female partici-

pants characterized by an average level of competition, who oriented their attention in the same

gaze direction of faces that during the social dilemma were associated with a competitive behavior,

irrespective of their gender. The distributional analysis showed that the gaze-cuing effect was

present for the fastest responses for both cooperative and competitive opponents. However, for

competitive opponents only, the effect increased for longer responses. This pattern of results sug-

14


gests that the type of prior interaction with the seen face modulates joint attention only at a later

stage, probably only after information associated to the seen face has been retrieved from memory.

3. EXPERIMENT 2

The results of Experiment 1 indicate that females characterized by an average level of

competition are more likely to orient their attention in the same gaze direction of faces that during a

prior interaction were associated with a competitive behavior. Since only average competitive

females were tested, it is not possible to assess whether this result represents a consistent behavior

within the female population or rather is influenced by the competitiveness level displayed by

participants, as occurs with individual differences in self-esteem (Willowski, Robinson, & Friesen,

2009), anxiety (Putman, Hermans, & Van Honk, 2006) and introversion/extraversion traits (Ponari,

Trojano, Grossi, & Conson, 2013).

Moreover, it is possible that in Experiment 1 the cooperation/competition manipulation

created a dominance hierarchy, in which faces associated with competitive outcomes were

identified as more dominant. Hence the effects observed could be due to perceived dominance of a

face rather than to the competitive behavior displayed during a previous interaction. Indeed,

dominance has been shown to affect gaze-cuing both in non-human primates (Shepherd, Deaner, &

Platt, 2006) and in humans (Jones et al., 2010). For instance, Shepherd et al. (2006) showed that

high-status monkeys were significantly more likely to follow the gaze of other high-status monkeys

than low-status monkeys, while the low-status monkeys tended to follow the gaze of all the other

monkeys.

The present experiment was aimed at testing these alternative interpretations. To this end, we

replicated Experiment 1 with two groups of females classified as highly or lowly competitive

according to the Competitiveness Index questionnaire (Smither & Houston, 1992; Houston et al.,

2000). If females tend to always follow the gaze of individuals associated to a competitive behavior,

then the gaze-cuing effect for competitive contenders should be present irrespective of the 15


individual level of competitiveness displayed by the participants. However, given the pivotal role

that gaze-triggered orienting of attention plays in social monitoring (e.g., Emery, 2000), individuals

who differ in the level of competitiveness may differently monitor social environment in goal-

directed tasks. More precisely, lowly competitive females, similarly to average competitive ones,

should be more likely to orient their attention in the cued direction only for faces of competitors,

since they may represent a potential obstacle to the achievement of their goal. On the contrary,

highly competitive individuals should be more likely to follow the gaze of others irrespective of the

outcomes, given that they tend to perceive others as potential rivals.

Differently, if the results of Experiment 1 are due to the fact that faces associated to a

competitive behavior are perceived as more dominant, then, in line with previous results (e.g.

Shepherd et al., 2006), lowly competitive individuals should be more likely to orient their attention

in the cued direction irrespective of the outcomes of a prior interaction with a cueing face since due

to their low competitiveness are likely to perceive others in general always as more dominant. As

the level of individual competitiveness increases, individuals should be more likely to follow only

the gaze of those faces associated to a competitive behavior.

3.1 METHODS

3.1.1 Participants

Thirty-two new undergraduate females (3 left-handed; M = 19.53 years, SD = 1.46 years)

from the University of Modena and Reggio Emilia received course credit to participate to the study.

All had normal or corrected-to normal vision and were naïve as to purpose of the experiment. The

study was conducted in accordance with the ethical standards laid down in the Declaration of Hel-

sinki, and fulfilled the ethical standard procedure recommended by the Italian Association of Psy-

chology (AIP). Written consent was obtained for all of them and they were debriefed about the

study at the end of the experiment.

16


They were selected from a larger sample (n=110) based on their scores at the Competitiveness

Index (CI) questionnaire (Smither & Houston, 1992; Houston et al., 2000). To be included in the

study, they had to score either in the high (12-20) or in the low (0-4) competitiveness range. Mean

scores were 15.56 (SD = 2.53) for the highly competitive group (n = 16) and 3.00 (SD = 1.26) for

the lowly competitive group (n = 16).

3.1.2 Stimulus, apparatus and procedure

Stimuli, apparatus and procedure were the same as those used in Experiment 1.

3.2 RESULTS AND DISCUSSION

3.2.1 Social dilemma

Overall, 46.1% of highly competitive participants and 56.3% of lowly competitive participants

decided to cooperate. A one sample t test (two-tailed) showed that these percentages did not differ

from the chance level of 50% (High: t(15) = .58, p = .57; Low: t(15)= .91, p = .38). The

cooperative choices of highly competitive participants did not differ from the chance level either

when the face belonged to a female (46.9%, t(15) = 0.42 p = .68) or when it belonged to a male

(60.9%, t(15) = 1.28, p = .22). Lowly competitive participants chose to cooperate more when the

face belonged to a female (51.6%) than when it belonged to a male (60.9%). This latter percentage

did not differ from the chance level of 50% (female face: t(15) = -0.19, p = .86; male face: t(15) =

1.28, p = .22). As for Experiment 1, this result suggests that the gender of the face did not affect

participants’ performance at the social dilemma.

3.2.2 Subjective Ratings

T tests for independent samples were used to compare the subjective ratings of the social

dilemma situation involving cooperative and competitive opponents. The scores for both highly and

lowly competitive groups significantly differed between cooperative and competitive opponents for

all dimensions (all ps< .001) (see Table 2).

17


The finding that the situation was judged as more competitive when the opponent displayed a

competitive behavior and as more cooperative when he/she displayed a cooperative behavior clearly

indicates that our manipulation was effective.

Social Relationship

CooperativeCompetitiv

e T p-value

CooperativeHighly 5.9 (0.3) 1.2 (0.4) 33.3 < .001

Lowly 5.9 (0.3) 1.1 (0.3) 37.0 < .001

CompetitiveHighly 1.2 (0.5) 5.2 (1.0) 12.0 < .001

Lowly 1.2 (0.6) 5.3 (0.7) 13.9 < .001

EasyHighly 4.9 (1.1) 2.8 (1.5) 3.8 = .002

Lowly 4.8 (0.8) 2.4 (1.0) 6.31 < .001

PleasantHighly 5.1 (1.1) 2.0 (1.3) 5.6 < .001

Lowly 4.9 (0.9) 1.7 (1.0) 8.93 < .001

PositiveHighly 5.3 (1.1) 1.9 (1.3) 5.9 < .001

Lowly 5.0 (0.7) 1.7 (1.0) 8.51 < .001

Table 2. Experiment 2: Mean subjective ratings (and standard deviations) of the social interaction with the opponent as a function of the opponent’s behavior (cooperative vs. competitive) for highly

and lowly competitive participants.

3.2.3 Gaze-cuing Responses

Practice trials, errors (3.5% of the total trials) and trials with RTs faster than 150 ms or slower

than 3000 ms (0.1% of the total trials) were excluded from the analyses.

18


Correct mean RTs were entered into a repeated-measures analyses of variance (ANOVA)

with cue-target spatial congruency (congruent vs. incongruent) and social relationship (cooperative

vs. competitive) as within-participant factors and version of the social dilemma (version 1:

cooperative female opponents and competitive male opponents; version 2: cooperative male

opponents and competitive female opponents) and level of competition (high vs. low) as between-

participants factor. When necessary, comparisons were performed using paired samples t tests and

by correcting the p value for the number of comparisons (Bonferroni correction).

The analysis revealed a main effect of social relationship, F(1,28) = 9.06, p = .005, ηp2 = .14,

that interacted with the version of the social dilemma, F(1,28) = 4.65, p = .040, ηp2 = .24. Post-hoc

comparisons revealed that participants who performed version 2 of the social dilemma responded

faster to cooperative (M = 520 ms, SE = 15.50 ms, 95% CI from 489 to 552 ms) than competitive

opponents (M = 535 ms, SE = 17.17 ms, 95% CI from 500 to 571 ms). Differently, RTs for

cooperative and competitive opponents did not differ for participants who performed version 1

(cooperative opponents: M = 554 ms, SE = 15.51 ms, 95% CI from 522 to 586 ms; competitive

opponents: M = 551ms, SE = 17.17 ms, 95% CI from 516 to 587 ms). This result indicates that

responses on the gaze-cuing task were faster when the distractor’s face belonged to a cooperative

male. This finding is in line with studies on face recognition and memory (e.g., Maleay, 1996; Oda,

1999) which reported that faces of cooperative males are recognized less than when the same males

are displayed as competitive individuals. Thus, the overall faster performance in version 2 can be

explained by assuming that cooperative faces (male faces) interfered less with task performance.

The main effect of cue-target spatial congruency was significant, F(1,28) = 12.78, p = .001,

ηp2 = .310, indicating that participants were faster to identify the target when it appeared in the

gazed-at location (i.e., congruent trials, M = 534 ms, SE = 11.41 ms, 95% CI from 511 to 558 ms)

as compared to when it appeared in the opposite location (i.e., incongruent trials, M = 546 ms, SE =

11.78, 95% CI from 522 to 570 ms).

19


The three-way interaction between social interaction, cue-target congruency, and level of

competition was significant, F(1,28) = 4.72, p = .0538, ηp2 = .14. Separate analyses by the level of

competitiveness showed that the interaction between cue-target congruency and social interaction

was significant for the lowly competitive group, F(1,28) = 5.90, p < .05, ηp2 = .30. Post-hoc tests

showed that the difference between congruent and incongruent trials (i.e., gaze-cuing effect) was

significant (27 ms, 95% CI from 8 to 45ms) for competitive opponents (565 vs. 538ms, t(15) =

3.12, p Bonferroni corrected < .028), while no effect was evident (-6 ms, 95% CI from -22 to 9 ms) for

cooperative opponents (542 vs. 548 ms, t(15) = -.86, p Bonferroni corrected = 1.61) (see Figure 2). For the

highly competitive group, there was only a main effect of cue-target congruency, F(1,28) = 6.33, p

< .05, ηp2 = .31, with faster RTs in congruent (525 ms) than in incongruent (539 ms) trials. The

interaction between cue-target congruency and social interaction did not reach significance, F < 1.

These results indicate that the cooperative and competitive outcomes of a previous interaction

with a cuing face can modulate the gaze-cuing effect in female participants characterized by a low

level of competition, who oriented their attention in the same gaze direction of faces that during the

social dilemma were associated with a competitive behavior. Differently, the outcomes of a prior

interaction did not influence the gaze triggered orienting of attention in females characterized by a

high level of competition.

4. GENERAL DISCUSSION

The results of the present study demonstrate that the type of relationship (i.e., cooperative or

competitive) established during a previous interaction with a cuing face can modulate the gaze-

cuing effect in female participants characterized by low and average levels of competition, who

oriented their attention in the same gaze direction of faces that during the social dilemma were

associated with a competitive behavior, irrespective of their gender. Differently, females

characterized by a high level of competition were not affected by a prior cooperative or competitive

interaction with the cueing face. This result allows us to exclude that the results of Experiment 1 20


were due to the cooperation/competition manipulation leading to the emergence of a dominance

hierarchy. Furthermore, they suggest that individuals characterized by different levels of

competitiveness may differently monitor the social environment when engaged in goal-directed

tasks.

The results of the present study are in line with prior studies suggesting that joint attention is

not immune to social modulations but they extend these results in two novel ways. First, they show

that, not only specific identity cues of an observed face, such as social status (Dalmaso et al., 2012),

political affiliation (Liuzza et al., 2011), race (Pavan et al., 2011), and age (Ciardo et al., 2014), but

also whether he/she decided to cooperate or compete during a prior interaction can modulate the

gaze-cuing effect. Interestingly, this result confirms the carry-over effect of competition found in

previous studies (e.g., Iani et al., 2014; Sessenberg et al., 2007) since the effects of competition

introduced in the social dilemma game were still evident and affected performance in the

subsequent gaze-cuing task. Second, they show that there is a strong tendency to orient attention in

the same direction of the gaze of those individuals that may represent an important source of

information and may be relevant for the attainment of our goals, even though these individuals may

be categorized as out-group members, and irrespective of their gender.

In competitive situations it may be fundamental for the observer to orient attention to others’

actions in order to monitor their progress toward their goals (Poortvliet & Darnon, 2010). Following

a competitor’s gaze may represent an highly adaptive behavior, as it allows a constant monitoring of

his/her intentions and, consequently, it allows the observer to plan the more adaptive behavior to

maximize the chance of achieving his/her goals. It is therefore possible that the type of relationship

established with others biases attention toward those individuals that are more salient in the social

environment (Ristic & Kingstone, 2005) because of the role that they could play in favoring or

hindering the attainment of our personal goals. In support of this line of thoughts are the results of a

series of studies showing that pictures of non-cooperative individuals attract more automatic

attention than pictures of cooperative individuals (Vanneste et al., 2007) and that faces of cheaters 21


and partners are different encoded into memory, with those of cheaters being memorized more

accurately than those of non-cheaters (e.g., Chiappe et al., 2004; Mealy, Daood, & Krage, 1996;

Oda, 1997; Yamagishi et al., 2003), possibly due to beliefs of trustworthy and personality traits that

we implicitly associate to them (Bayliss & Tipper, 2006). Our results also support the proposal that

the gaze-triggered orienting is augmented under conditions characterized by a low relational value

(Wilkowski, Robinson and Friesen, 2009), thus pointing up the pivotal role that gaze-triggered

orienting of attention plays in social monitoring (Pickett & Gardner, 2005).

Since we tested only female participants, we do not know whether our results may extend to

males. It is however possible that they do not generalize given the reported gender differences in

sensitivity to social cues (e.g., Bayliss et al., 2005; Geary, 2010 for a review) and in emotional

responses to cooperation and competition (e.g., Kivikangas, Kätsyri, Järvelä, & Ravaja, 2014).

Future target studies should address this issue.

To conclude, the present study shows, for the first time, that different types of social

interactions may modulate joint attention differently. The present results shed light on the role of

competition in modulating gaze-mediated attention, suggesting that during social interactions more

attentional resources are allocated to those individuals with greater social relevance and from whom

we can draw more information to achieve our goals.

22


Funding

PR was supported by a grant from Università di Milano - Bicocca (Fondo di Ateneo 2012).

23


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Table and Figure captions

Table 1. Experiment 1: Mean subjective ratings (and standard deviations) of the social interaction

with the opponent as a function of the opponent’s behavior (cooperative vs. competitive).

Table 2. Experiment 2: Mean subjective ratings (and standard deviations) of the social interaction

with the opponent as a function of the opponent’s behavior (cooperative vs. competitive) for highly

and lowly competitive participants.

Figure 1. Illustration of the gaze-cuing procedure depicting examples of stimuli (not drawn to scale)

and sequence of events for a spatially congruent trial (top) and a spatially incongruent trial

(bottom).

Figure 2. Mean RTs (± s.e.m.) in ms, collapsed across versions, for spatially congruent (grey) and

incongruent (black) trials as a function of the social relation with the cuing face for Experiment 1

(panel a) and Experiment 2 (panel b). Asterisks denote significant differences.

Figure 3. Experiment 1: Magnitude of the gaze-cuing effect (± s.e.m.) in ms for the competitive

(dotted line) and cooperative (solid line) social relation conditions as a function of bin.

30


Table 1

Social Relationship

Cooperative Competitivet p-value

Cooperative 5.2 (0.7) 1.8 (0.7) 12.3 < .001

Competitive 2.2 (1.1) 4.9 (1.0) -6.7 < .001

Easy 4.8 (0.9) 2.7 (0.8) 8.7 < .001

Pleasant 4.7 (0.7) 2.1 (0.7) 10.0 < .001

Positive 4.9 (0.9) 2.0 (0.7) 10.0 < .001

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Table 2

Social Relationship

CooperativeCompetitiv

e t p-value

CooperativeHighly 5.9 (0.3) 1.2 (0.4) 33.3 < .001

Lowly 5.9 (0.3) 1.1 (0.3) 37.0 < .001

CompetitiveHighly 1.2 (0.5) 5.2 (1.0) 12.0 < .001

Lowly 1.2 (0.6) 5.3 (0.7) 13.9 < .001

EasyHighly 4.9 (1.1) 2.8 (1.5) 3.8 = .002

Lowly 4.8 (0.8) 2.4 (1.0) 6.31 < .001

PleasantHighly 5.1 (1.1) 2.0 (1.3) 5.6 < .001

Lowly 4.9 (0.9) 1.7 (1.0) 8.93 < .001

PositiveHighly 5.3 (1.1) 1.9 (1.3) 5.9 < .001

Lowly 5.0 (0.7) 1.7 (1.0) 8.51 < .001

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Figure 1

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Figure 2

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Figure 3

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