electromyographic analyses of responses to intergroup threat

Electromyographic Analyses of Responses toIntergroup Threat

Mark D. Davis1

University of West AlabamaWalter G. Stephan

New Mexico State University

Two studies tested predictions from intergroup threat theory concerning emotionalresponses to intergroup threat. Study 1 employed threatening video clips of the9/11/01 World Trade Center attacks. Study 2 employed video clips of a threatening“opponent” in a competition. Facial electromyography (EMG) was employed tocapture emotion-related muscle activity. As participants viewed videos in Study 1,they were instructed to consider Americans’ reactions or their personal reactions. InStudy 2, an “opponent” presented individually directed or group-directed stereotypethreat. Both studies provide support for the theory: Participants experiencing indi-vidual threats displayed greater EMG activity in muscles corresponding to inwardlydirected emotions (fear), while participants experiencing group threats displayedgreater EMG activity in muscles corresponding to outwardly directed emotions(anger).jasp_709 196..218

We live in a world where threats seem to be omnipresent. These threatsinclude those posed by terrorism, global warming, economic insecurity, envi-ronmental degradation, pandemic diseases, crime, globalization, and loss oftradition and cultural/ethnic identity, among others. Threat is experiencedwhen there is a perception of potential physical or psychological harm tooneself or one’s group, and there are insufficient resources to cope with thesource of the threat (Blascovich, Mendes, Hunter, & Lickel, 2000).

Blascovich et al. (2000) contrasted threat with the experience of feelingchallenged, where it is perceived that there are sufficient resources to copewith the source. The most basic responses to perceptions of threat are toengage with the source of potential harm or remove oneself from the poten-tial of harm: the fight-or-flight syndrome. Perceptions of threat have a varietyof other effects on people as well. The immediate effects often include bothphysiological and psychological reactions. Some of the more extreme physi-ological reactions (e.g., increases in blood pressure; Mendes, Blascovich,Hunter, Lickel, & Jost, 2007) put people at risk of cardiac or vascularproblems. Psychological reactions include decrements in performance andlosses in self-esteem (Steele, 1997; Steele & Aronson, 1995). These problems

1Correspondence concerning this article should be addressed to Mark D. Davis, Universityof West Alabama, Station 22, Livingston, AL 35470. E-mail: [email protected]

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Journal of Applied Social Psychology, 2011, 41, 1, pp. 196–218.© 2011 Wiley Periodicals, Inc.

are created, in part, by negative emotional responses to the expectation ofharm from the source of the threat (Herrald & Tomaka, 2002; Tomaka,Blascovich, Kelsey, & Leitten, 1993).

The types of threat of interest to us are those that involve intergrouprelations. Intergroup threats occur when members of an in-group perceivethat an out-group poses a threat to the welfare of the in-group as a wholeor its members individually. In the studies reported in the present article,intergroup threat theory (ITT) was used as a basis for examining emo-tional reactions to intergroup threats (Stephan & Renfro, 2002; Stephan,Ybarra, & Rios-Morrison, 2009). According to ITT, threats from out-groups may be perceived as either realistic or symbolic, and can be directedtoward either the individual group member or toward the group as a whole.Thus, there are four basic categories of threat: realistic group threats arethreats to the in-group’s power, wealth, or physical well-being; symbolicgroup threats are threats to the ideologies or values of the in-group; real-istic individual threats are threats to the well-being of the individual; andsymbolic individual threats are threats to the individual’s beliefs or self-identity. The degree to which people perceive they are threatened has beenfound to be influenced by such factors as in-group identification, negativecontact with the out-group, a history of conflict between the in-group andout-group, and status inequalities between the two groups (Stephan &Stephan, 2000).

The literature suggests that people experience a wide range of emotionalreactions in response to intergroup threats, including fear, anger, contempt,sadness, and disgust (Brewer & Alexander, 2002; Devos, Silver, Mackie, &Smith, 2002; Mackie, Maitner, & Smith, 2009; Neuberg & Cottrell, 2002).Emotional reactions to intergroup threats can be classified according towhere attention is focused. Intergroup emotions can be categorized into thosethat are outwardly focused toward others and those that are inwardlyfocused on the self. Outwardly focused emotions (e.g., anger, frustration) aregenerally directed toward the source of the threat. They constitute nonverbalsignals to both the in-group and the out-group that a threat exists (Neu-berg & Cottrell, 2002; Stephan & Renfro, 2002). They also prepare the bodyfor stress (Kemeny, 2003) and may motivate coping behaviors(Lazarus & Folkman, 1984) directed against the out-group (e.g., aggression).Inwardly focused emotions (e.g., fear, anxiety) can also serve as nonverbalsignals that a threat exists and prepare the body for stress, but they typicallymotivate intentions to escape (Devos et al., 2002; Neuberg & Cottrell, 2002;Stephan & Renfro, 2002).

In the ITT, it is proposed that individual and group threats have differenteffects on outwardly and inwardly focused emotions. Specifically, Stephanand Renfro (2002) suggested that

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It is likely that threats to the group lead to emotional reactionsthat are more outwardly directed (e.g., anger toward the out-group or resentment of the out-group) than inwardly directed(e.g., fear that I won’t perform well, feelings of helpless-ness). . . . In contrast, individual threats may have the reverseeffect, leading to more inward than outward emotional reac-tions. (p. 202)

The reason threats to the in-group as a whole elicit outwardly directedemotional responses is that they draw attention to the needs and welfare of theentire in-group. In contrast, individual threats elicit inwardly directed emo-tional responses because they draw people’s attention to their own welfare.

It is important to note that there are other types of inwardly and outwardlydirected emotions that differ from those already mentioned. For example,another set of inwardly directed intergroup emotions (sadness, helplessness,humiliation) signals feelings of loss and may motivate behaviors or behavioralintentions for seclusion (Neuberg & Cottrell, 2002; Stephan & Renfro, 2002).A different set of outwardly directed intergroup emotions (contempt, disgust)motivate action to avoid or isolate (e.g., quarantine) the out-group(Kurzban & Leary, 2001; Neuberg & Cottrell, 2002). We consider these typesof emotional reactions to be less likely to occur than fear or anger and, as aconsequence, we elected not to examine them in the studies that follow.

There is considerable controversy over how emotions should be measuredor if they even can be measured (Barrett, 2006; Barrett et al., 2007; Ekman,1992; Izard, 2007; Ortony & Turner, 1990; Panksepp, 2007; Russell, 1995).For researchers who take the natural view of emotions (e.g., Izard, 2007;Panksepp, 2007), humans have basic innate emotions that are universal andinvolve unique physiological patterns that can be measured (e.g., Ekman,1992; Levenson, Ekman, & Friesen, 1990). For other researchers, there areno innate emotions, but rather there is a core of affect that is divided intocategories based on prior experience (Barrett, 2006; Barrett et al., 2007;Russell & Barrett, 1999). From this perspective, in order to measure emo-tions, it is necessary to have an understanding of the situational contexts inwhich emotions are experienced and expressed in a given culture. Thus,emotions are thought to be socially constructed, not innate. In Americanculture, where these studies were conducted, it appears that fear and angerare considered to be normative responses to threat (Brewer & Alexander,2002; Devos et al., 2002; Neuberg & Cottrell, 2002; Stephan & Renfro, 2002),which makes them viable candidates for study, even from a social construc-tivist perspective.

There are also disputes about techniques of measuring emotions. Themost widely used techniques have both strengths and weaknesses. For

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instance, self-reports have the advantage of assessing the subjective experi-ence of emotion through introspection. However, research indicates thatpeople are often unaware of the emotions they are experiencing(Cacioppo & Petty, 1983) or are unable to verbalize the emotions, particu-larly in ambiguous situations (Barrett, 2006). In addition, self-reports arecommonly obtained retrospectively, which may limit their accuracy.Although it is possible through such techniques as protocol analysis (Eric-sson & Simon, 1993) to obtain self-reports at the time emotions are expe-rienced, these techniques may interfere with the natural expression ofemotion.

Physiological measures also have been widely used to assess the correlatesof emotional experiences, such as positive versus negative affect (e.g.,Cacioppo, Berntson, Larsen, Poehlmann, & Ito, 2000), threat and challenge(e.g., Tomaka et al., 1993), and prejudice (e.g., Vanman, Paul, Ito, & Miller,1997; Vanman, Saltz, Nathan, & Warren, 2004). However, physiologicaltechniques have both strengths and weaknesses. Their major advantage isthat they provide real-time, objective measures of correlates of emotions.Among their disadvantages is that measuring emotions in this manner can becumbersome and obtrusive, which may make it difficult to capture sponta-neously experienced emotions.

One physiological technique that offers advantages for testing the emo-tions relevant to the research we wished to conduct is electromyography(EMG), which entails recording the reactivity of facial muscles involved inthe display of emotions. EMG can be used to measure covert as well as overtemotional expressions (Tassinary & Cacioppo, 2000). Using EMG, it is alsopossible to measure muscle activation below the level that is visually detect-able. In addition, EMG can be used to detect emotional responses before theindividual has an opportunity to inhibit the outward display of an emotion.Thus, EMG is an excellent technique to examine immediate, spontaneousemotional responses to events.

In previous research, it has been shown that muscles in the brow region(corrugator supercilii) are activated during negative affect (Cacioppo et al.,2000; Vanman et al., 2004). Other studies have found that these muscles mayonly be activated by specific negative emotions (e.g., anger; Moody, McIn-tosh, Mann, & Weisser, 2007), whereas other negative emotions may notactivate them at all. Miller, Patrick, and Levenston (2002) showed that“Greater EMG corrugator activity was observed during anger, as comparedto fear imagery” (p. 526). Similarly, Yartz and Hawk (2002) reported that“Corrugator activity may be sensitive to aversiveness associated with avariety of negative emotions, but not fear” (p. 66). Thus, this research sug-gests that the corrugator muscles are not involved in the emotional expres-sion of fear.


Other researchers have found that activation of the medial frontalismuscles are an indicator of fear (Ekman & Friesen, 1978; Moody et al., 2007;Smith, 1989). On the basis of the Facial Action Coding System (FACS),Ekman and Friesen argued that during the emotional expression of anger,the corrugator muscles are active, causing the eyebrows to be drawn downand in. However, for the emotional expression of fear, the medial frontalismuscles contract, producing wrinkles on the forehead. Ekman and Friesenalso argued that the frontalis is not activated by anger. In support of theconnection between EMG and FACS, Ekman (1982) reported that EMGsignals are highly correlated with the FACS facial expressions. On the basisof EMG and FACS research, it appears that the frontalis muscles are moreactive than are the corrugator muscles during the expression of fear, whereasthe corrugator muscles are more active than are the frontalis muscles duringthe expression of anger.

In the two studies reported in this article, participants were exposed toeither individual- or group-level threats, and their emotional responses tothe threats were measured using EMG. In the first study, the participantsviewed videotapes of the 9/11 terrorist attacks on the World Trade Center.While doing so, they were instructed to focus on either Americans’ reactionsto these events or their own personal reactions. In the second study, theparticipants expected to play a competitive intellectual game against anout-group opponent. Prior to the game, they viewed a videotape of theopponent, who made stereotype-based remarks directed at the intellectualabilities of their group or the participant’s own abilities based on member-ship in the stereotyped group. It is predicted that when processing a threatto their in-group, participants will display greater activity levels in the cor-rugator muscles than in the frontalis muscles because group threats focusconcern on the welfare of the group, and this leads to outwardly directedemotions (e.g., anger). In contrast, when processing an individual-levelthreat, it is expected that participants will display greater activity levels inthe frontalis muscles than in the corrugator muscles because individualthreats focus concern on their own welfare, leading to inwardly directedemotions (e.g., fear).

Study 1

Method

Participants and Design

Study participants were 28 students (13 males, 15 females) at New MexicoState University who received experimental credit for their participation. The


students were randomly assigned to one of two conditions in a 2 (InstructionType: individual threat vs. group threat) ¥ 2 (EMG Placement: frontalis vs.corrugator) mixed-factorial design with the second variable (frontalis vs.corrugator) being within-participants. There was an equal number (n = 14) ofparticipants in each of the threat groups.

Participants’ ages ranged from 18 to 23 years (M = 19.1 years). Theethnicity of participants was primarily Caucasian (49%) and Hispanic (33%),with 7% Native American, 4% African American, and 7% “other.” All of theparticipants were U.S. citizens.

Materials

Threat stimuli. The threatening stimuli consisted of videotape footagefrom the September 11, 2001, terrorist attacks on the World Trade Center(WTC) in New York City. The video was 3 min in duration. It was brokendown into six alternating segments of non-action footage and action footage,each 30 s long.

The action footage contained shots of the buildings being struck by theplanes, the towers falling, people running away from the buildings, andpeople’s reactions during these events. The non-action footage consisted oftwo firefighters in conversation well before 9/11, with the WTC towers behindthem, as well as silent distance shots of the two towers burning, taken fromhelicopters circling the WTC towers.

Instructions. Before viewing the videotape, participants were presentedwith one of two sets of instructions. These instructions were designed toinfluence the manner in which participants processed the videotape.

One set of instructions focused participants’ attention on their own indi-vidual reactions to the events of 9/11. It reads “What you are about to see areclips from the 9/11 attacks on the World Trade Center towers. While youwatch the clips, keep in mind how you personally felt during the attacks”(individual-threat condition).

The other set of instructions focused participants’ attention on howAmericans as a group reacted to the events of 9/11. It reads “What you areabout to see are clips from the 9/11 attacks on the World Trade Centertowers. While you watch the clips, keep in mind how Americans felt duringthe attacks” (group-threat condition).

Physiological measures. A ProComp biofeedback machine (withMyoScan-Pro sensors) was used to acquire facial EMG. The MyoScan-Prosensor’s bandwidth is up to 500 Hz and automatically converts the signal toa root mean square signal (an analogue rectification was performed by theProComp biofeedback machine). The MyoScan-Pro sensors pre-amplify


the signal to reduce noise, with a common mode rejection ratio(CMRR) > 130 db. This amplification process increases accuracy when mea-suring across differing small voltages. The sensor’s input range is 0 to 400Vrms (volts root mean square; for a review of Standards for Reporting EMGData, see Merletti, 1999). The sampling rate was 500 Hz.

Following Fridlund and Cacioppo’s (1986) guidelines for facial EMG,pre-gelled facial EMG Ag/AgCl electrodes (0.25 cm diameter center detec-tion surface, with a 1.00 cm interdetector surface spacing) were placed on theparticipant’s left medial frontalis and left corrugator supercilii, with thegrounding electrode placed on the lower left earlobe (see Figure 1). Eachplacement site was cleaned and gently abraded to increase conductivity andto reduce inter-electrode impedance. The electrode cords were secured toreduce annoyance, and to remove distraction or obstruction in vision. Ahabituation period (10 min) was used to get participants acclimated to theelectrodes. The experimenter sat in an adjacent room during the habituationand experimental portions of EMG data collection.

The two electrode placements were used to account for the facial expres-sions of inward (e.g., afraid/fearful; frontalis) and outward (e.g., anger/frustration; corrugator) emotional displays (e.g., Ekman & Friesen, 1978;Miller et al., 2002; Moody et al., 2007; Yartz & Hawk, 2002). Prior to analy-sis, the data were transformed by denoising in quadrature (square root of thesquared raw signal, minus the squared minimum amount of activity observedin that region; e.g., Fridlund & Cacioppo, 1986; Fridlund, Cottam, & Fowler,1982; Fridlund, Schwartz, & Fowler, 1984). This transformation wasemployed to “make equivalent the outputs of multiple EMG channels”

Figure 1. Facial EMG electrode placements.


(Fridlund & Cacioppo, 1986, p. 577), which allows for the optimization of thesignal-to-noise ratio.

There were no differences between baseline activity levels in either of themuscles or in the two instruction conditions ( ps > .05). Because baselineactivity levels did not systematically vary as a function of experimentalcondition (Tassinary & Cacioppo, 2000), each participant’s baseline wassubtracted from the mean of each second of the action sequences to createchange scores for the analyses to investigate the change in EMG frombaseline to experimental manipulation.

Procedure

When participants entered the laboratory, they were informed that thepurpose of the study was to investigate physiological reactions to emotionalstimuli. Next, all participants were told that their facial muscle electricalactivity would be measured.

After they signed the consent form, which explained that videotapes of the9/11 attacks would be shown, the participants were escorted into the experi-mentation room that contained a TV/VCR, chair, electrode cords, electrodes,and electrode preparation supplies. The participant was prepared for elec-trode placement, and the electrodes were placed on the participant’s face. A10-min acclimation period was employed to help the participant becomeaccustomed to the electrodes. After the 10-min period, the experimenteradministered the instructions, then left the room and remotely turned on thevideo. Event markers were placed on the computer EMG recording corre-sponding to the beginning of the video, at each transition between non-actionand action sequences, and at the end of the video. After the video ended, theelectrodes were removed, and each participant was carefully debriefed andthanked for his or her participation.

Results

Initial Analyses

The activity levels of each of the two muscles were averaged separatelyover the first 15 s of the first non-action segment to create a baseline. In anattempt to determine if the action segments produced emotional responses,activity levels for each muscle (combining across the two threat conditions)for the initial baseline non-action segment were compared to activity levelsfor the initial action segment (again, combining across the two threat


conditions). For the frontalis, the analysis shows an increase in muscleactivity from the baseline (M = 13.39, SD = 22.30) to the mean for the firstaction sequence (M = 72.49, SD = 82.77), t(27) = 4.87, p < .01. A significantincrease in muscle activity level from the baseline (M = 37.58, SD = 77.76)to the average of the first action sequence (M = 67.28, SD = 119.92) wasalso found for the corrugator, t(27) = 2.28, p < .05. These results indicatethat the threat manipulations were successful in producing both fear andanger.

Primary Analyses

The raw data means for the baseline and Action Sequence I as a func-tion of facial muscle and type of threat are presented in Figure 2. In orderto test the hypotheses, the change scores reflecting the difference betweenthe baseline and Action Sequence I for each participant were employed.These change scores were then subjected to a z-score transformation tomake it possible to compare activity levels directly between the two differ-ent facial muscles.

For a test of the hypotheses, we used a 2 (Instruction Type: individualthreat vs. group threat) ¥ 2 (EMG Placement: corrugator vs. frontalis)MANOVA. The dependent variable consisted of muscle activity levels acrossall three action sequences. This analysis reveals the predicted two-wayinteraction between instruction type and EMG placement, Wilks’s L = .86,F(1, 26) = 4.24, p < .05 (see Figure 3).

We conducted follow-up analyses to test the hypotheses that individualthreat would lead to greater activity levels in the frontalis than in the cor-rugator, while group threat would lead to greater activity levels in thecorrugator than in the frontalis. The relevant comparisons reveal thatfor participants in the individual-threat condition, EMG activity for thefrontalis muscle (M = 0.31, SD = 1.24) was marginally greater than wascorrugator muscle activity (M = -0.24, SD = 0.38), F(1, 26) = 2.83,p = .10. The comparison in the group-threat condition for the frontalis(M = -0.31, SD = 0.58) and corrugator (M = 0.24, SD = 1.34) failed toreach significance, F(1, 26) = 1.40, p = .21, although it was in the predicteddirection.

Discussion

The results of Study 1 provide support for the hypotheses. The predictedtwo-way interaction was obtained. However, the relevant contrast effects,


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Figure 2. Raw EMG baseline and mean of Action Sequence I as a function of facial muscles andtype of threat: Study 1.


while clearly in the predicted direction, were nonsignificant or only margin-ally significant. One reason for the failure to find stronger effects may be thatthere were no images of out-group targets available toward which angercould be directed. The videos showed only the victims of the 9/11 attacks anddid not show the perpetrators, which may have limited the amount of angerexpressed in the group-threat condition.

Another limitation of this study is that the threat was purely vicarious.The events depicted in the video occurred to other people in the past,although participants could easily have felt, as did many Americans, thatfuture attacks of a similar nature are possible.

A third factor that may have limited the magnitude of the obtained effectsis that the baseline measure was gathered while the videotapes showed theWTC months before the attack. It is possible that these scenes also activatedemotional responses (as evidenced by the means for the raw EMG baselinedata), even though no destruction was shown. Any such emotional responseswould act to reduce the magnitude of the change scores from the baseline tothe action scenes, which showed the actual destruction of the WTC. Theseissues are addressed in Study 2.

Figure 3. Mean change z-score levels as a function of EMG placements and type of threat.


Study 2

Study 2 is a replication of Study 1, but with a more direct threat manipu-lation, a target toward which anger could be expressed, and an improvedbaseline measure. For this study, the threat originated from an “opponent”in a competitive intellectual game. The threats were stereotype-based(Steele & Aronson, 1995) and were directed toward the ethnic group as awhole or toward the participant as a member of the stereotyped group.

The participants in this study were all Hispanics, who are stereotyped asless academically proficient than Caucasians (Aronson, Quinn, & Spencer,1998; Aronson, Steele, Salinas, & Lustina, 2008). Aronson et al. (2008) spe-cifically researched stereotype threat on minorities and found that Hispanicsare subject to academic-related stereotype threats (Aronson & Salinas, 1998,as cited in Aronson et al., 2008).

The opponents in this study were Caucasians. In most studies of stereo-type threat, the focus is on the effects of stereotype threat on performance,but in the present study, the focus was on the effects of stereotype threats onemotional reactions. The stereotype threat literature does not make a distinc-tion between threats that are directed to the group as a whole and those thatare directed at individuals because of their membership in the stereotypedgroup. However, that distinction is crucial to ITT and is the focus of Study 2.Also, it is worth noting that in the ITT, stereotype threat is considered to bea symbolic threat because it can undermine self-esteem (Stephan et al., 2009).

The emotions targeted were the same inwardly directed and outwardlydirected emotions that we employed in Study 1 (i.e., anger and fear). Again,they were measured through facial EMG.

Method

Design

Study participants were 42 Hispanic male participants from New MexicoState University who received experimental credit for their participation.Participants’ ages ranged from 18 to 29 years (M = 19 years). Of the partici-pants, 22 were randomly assigned to one of two experimental conditions in a2 (Instruction Type: individual threat vs. group threat) ¥ 2 (Muscle: frontalisvs. corrugator) mixed-factorial design, with the second variable (frontalis vs.corrugator) being within-participants. For instruction type, 10 participantswere in the individual-threat condition, while 12 were in the group-threatcondition.

The remaining 20 participants were randomly assigned to one of twocontrol conditions (n = 10 in each control condition). Participants in the


control conditions did not receive the intergroup threats. They were onlypresented with background information about the “opponent.” They wereincluded to determine if the ethnicity of the opponent was enough by itselfto elicit negative emotional reactions. In these two control conditions, theopponent was either a Caucasian or Hispanic male. Participants’ ethnicitywas determined through self-report.

Materials

Threat stimuli. The threatening stimuli consisted of videotape footage ofan “opponent” discussing personal information under the guise of providingthe participant with information in preparation for a competitive game thatwould take place face to face at the end of the “preparation” phase. Therewere four video clips. All four clips included background information aboutthe opponent. The two clips that were used to test the hypotheses included, inaddition, either an individual- or group-directed stereotype threat. These twoclips featured the same Caucasian opponent. The two clips for the controlconditions included only the background information, which was presentedby the Caucasian or a Hispanic opponent.

Confederate script. The script for the videotape clips of the confederateall contained the same background information. The segment is 22 s long:

My name is Ryan and I am 20 years old. I was born August 12,1984. I was born in Dallas, Texas, but my family moved aroundthe country while I was growing up. Las Cruces is a differentplace, but I like living here and going to NMSU. I am anengineering major, and I am taking psychology to fill a GE(general education requirement). My hobbies are playing theguitar, playing baseball and football, and hanging out with myfriends.

The individually directed stereotype threat also includes the following state-ments. This segment is 15 s long:

I see that my opponent is a Hispanic. That should make thiscompetition pretty easy, because I don’t see him doing well onthese kinds of tasks. I don’t mean to sound racist, but I believeI can beat this guy.

The group-directed stereotype threat contains the following statements. Thissegment is also 15 s long:


Is this study a kind of Hispanics versus Anglos thing? If it is, Ifigure the Hispanics will lose because they aren’t good at thesekinds of tasks. I don’t mean to sound racist, but I don’t seeHispanics beating Anglos.

Physiological measures. The same ProComp biofeedback machine andpreparation procedure were utilized for this study. Electrodes were againplaced on the left medial frontalis and the left corrugator supercilii, and thedata were denoised in quadrature. The baseline measure was recorded duringthe last minute of a 10-min acclimation period. This baseline measure wasused to provide an improved index of resting-level muscle activity.

Procedure

Participants were informed that the study was being conducted to inves-tigate physiological and psychological processes that are involved in compe-tition. All participants were shown the EMG machine, and it was explainedto them that the machine would be used to establish a baseline to compare tothe competition phase. The participants were told that their opponent was inan adjacent lab, and they would later engage in a face-to-face competitioninvolving intellectual tasks. Participants were asked to complete a demo-graphic form, and their picture was taken with a Polaroid camera. Theexperimenter explained that their opponent would be filming a short video inwhich they talked about the answers to the same demographic form. Theywere told that this clip would be e-mailed to the computer in their lab room.After the Polaroid picture was taken, the experimenter left the room, explain-ing that he was taking the demographic form and the Polaroid picture over tothe opponent’s lab room. When the experimenter returned, the participantswere prepared for electrode placement.

A 10-min acclimation period then began after the experimenter left theroom for external observation. The last minute of the acclimation period wasused for the baseline measure. The video of the opponent was then played.There were event markers placed on the computer corresponding to 1 minbefore the beginning of the video (baseline), at the beginning of the informa-tion segment, at the start of the threat segment, and at the end of thethreatening statements. Participants in the control conditions viewed theinformation clip only, while participants in the experimental conditionsreceived the information clip and one of the threat clips.

After the video ended, the experimenter returned and removed the elec-trodes. Participants then completed the remainder of the questionnaires.Finally, the participants were carefully debriefed.


Results

Initial Analyses

As in Study 1, to determine if there was an increase in muscle activity foreach muscle from the baseline, two preliminary t tests were performed tocompare the baseline activity levels with the muscle activity scores of thethreat segment. For the frontalis, the analysis shows a significant increase inmuscle activity from the baseline (M = 2.46, SD = 2.06) to the threat segment(M = 3.84, SD = 2.96), t(21) = 3.68, p < .01. A significant increase in muscleactivity level from the baseline (M = 2.03, SD = 1.65) to the threat segment(M = 3.66, SD = 2.39) was also found for the corrugator, t(21) = 4.48, p < .01.These results indicate the occurrence of emotional expressions as a result ofthe threat.

In addition, we performed an omnibus 4 (Condition: Hispanic control,Caucasian control, individual threat, or group threat) ¥ 2 (Time: baseline vs.information) ¥ 2 (EMG Placement: frontalis vs. corrugator) MANOVA toinvestigate any differences between the control conditions. This analysisreveals no significant effects, Wilks’s L ps > .20. Thus, there were no mean-ingful baseline differences among the threat or control conditions, no differ-ences between the baseline and the information clip, and participants reactedin a similar manner, regardless of the ethnicity of their opponent.

Primary Analyses

The raw data means for the baseline and the threat segment as a functionof facial muscle and type of threat are presented in Figure 4. In order to testthe hypotheses, we employed change scores reflecting the difference betweenthe baseline and threat segment for each participant. As in Study 1, thesechange scores were then subjected to a z-score transformation to make itpossible to compare activity levels directly between the two different facialmuscles. To test the hypotheses, we utilized a 2 (Threat Type: individual vs.group) ¥ 2 (EMG Placement: frontalis vs. corrugator) MANOVA. The testproduced the predicted two-way interaction of threat type and EMG place-ment, Wilks’s L = .49, F(1, 20) = 21.23, p < .01 (see Figure 5). All of the othermultivariate effects were nonsignificant ( ps > .10).

In a breakdown of the two-way interaction, the analyses further indicatethat for participants receiving the individual-threat video, there was a greaterz-score change from baseline in the frontalis muscle (M = 0.48, SD = 1.16)than in the corrugator muscle (M = -0.58, SD = 0.78), F(1, 20) = 5.04,p < .05. In contrast, for the participants receiving the group-threat video,


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Threat segment

Figure 4. Raw EMG baseline and mean of the threat segment as a function of facial muscles andtype of threat: Study 2.


there was a greater z-score change in the corrugator muscle (M = 0.49,SD = 0.92) than in the frontalis muscle (M = -0.40, SD = 0.65), F(1,20) = 8.45, p < .01.

Discussion

The results of Study 2 replicate the two-way interaction of Study 1, andclearly demonstrate the predicted results. Participants receiving the individu-ally directed stereotype threat displayed greater activity in the frontalismuscle than in the corrugator muscle. Thus, an inwardly directed emotionalresponse (fear) was stronger than was an outwardly directed emotionalresponse (anger) following the individual threat. In contrast, participantsreceiving the group-directed stereotype threat displayed greater activity in thecorrugator muscle than in the frontalis muscle, indicating that the outwardlydirected emotional response was greater than was the inwardly directedemotional response following a group threat.

It is worth noting that the increase in fear found in the individual-threatcondition is consistent with the contention of stereotype threat theorists thatsuch threats lead to anxiety, which may then have a negative impact on

Figure 5. Mean change z-score levels as a function of EMG placements and type of threat.


performance (Aronson et al., 1998; Schmader, Johns, & Forbes, 2008). Inaddition, it was found that the group threat led to anger. Although this studydid not examine performance, it would be interesting to know if angercreated by group-based stereotype threat would interfere with subsequentperformance.

In both studies, there is a possibility that informing participants of thepurpose of the EMG measure (i.e., to assess physiological reactions) mighthave interfered with spontaneous emotional reactions by either inhibiting orexaggerating facial muscle reactivity. The authors believe that inhibition wasnot a problem in this study because emotional reactions to these stimuli wereso fleeting that they were unlikely to have been subject to conscious inhibi-tion. If inhibition had occurred, it would only have decreased the chances ofobtaining the predicted effects (because inhibition would have limited therelative magnitude of the recorded responses), but the predicted effects wereobtained. If exaggerated emotional responses had occurred, electrical activitywould most likely have spread to the other electrode site, and this was notobserved in the data.

General Discussion

Both studies demonstrate the influence of intergroup threats on emotionalexpressions. Participants who received an individual-level, intergroup threatresponded with greater activity in a facial muscle (frontalis) that is associatedwith inwardly directed emotions (fear, anxiety); whereas participants whoreceived a group-level threat responded with greater activity in a facialmuscle (corrugator) that is associated with outwardly directed emotions(anger, frustration). The emotions elicited by intergroup threats are likely tomotivate behaviors or behavioral intentions that would aid individual andgroup adaptation. When people are threatened as individuals, fear may be anadaptive response because it is likely to lead to avoidance of confrontation,and thus reduces the potential for injury, especially when the individualperceives herself or himself to be weak in comparison to the threateningout-group. In contrast, when one’s in-group as a whole is threatened, angermay be adaptive because it will motivate behavior that could eliminate thethreat (Mackie, Devos, & Smith, 2000), especially when the in-group isperceived to be stronger than the threatening out-group.

The results in the group-threat condition appear to be inconsistent with aprediction made in intergroup emotions theory (IET; Devos et al., 2002). Inthis theory, it is predicted that anger will be produced when a threatenedin-group perceives itself to be stronger/more powerful than the threat-ening out-group. In Study 2, the threatened group was a minority group


(Hispanics), and it is unlikely that they felt more powerful than the group towhich the threatening opponent belonged (Caucasians), but nonetheless theyexperienced more anger than fear. Thus, when one’s in-group is threatened,anger may be the initial response, regardless of the relative power of theout-group.

Another prediction from IET fared better. The IET predicts that fear willbe produced if in-group members feel weak, compared to the threateningout-group. The IET prediction is consistent with the findings in the individualinstruction condition of Study 1 in which the participants may have feltrelatively helpless (albeit vicariously) in the face of the terrorist attacks, andwith the findings of the individual-threat condition in Study 2, where theHispanic participants may have perceived their Caucasian opponent as morepowerful than they were.

The effects of power on emotional reactions to threat may vary as afunction of whether the threat is directed at an individual in-group memberor the in-group as a whole. In the case of group threats, a perception that thein-group possesses less power than a threatening out-group could easilytransform an initial anger response into fear if in-group members believe thatthey lack the ability to defend themselves against the threatening out-group.In contrast, if in-group members perceive that the in-group possesses greaterpower than does the out-group, feelings of contempt may be added to theiranger if the weak out-group is perceived to be morally inferior (Kurzban &Leary, 2001; Neuberg & Cottrell, 2002).

In the case of individual threats, individual in-group members are likely tofeel fear, regardless of the amount of power they or their group possess,because they are likely to believe they are outmanned. In addition, they mayfeel depression or hopelessness if they perceive that they lack the ability tocontrol their outcomes. The effects of perceptions of low or high power onemotional reactions in intergroup settings should be addressed in futureresearch.

The results of these studies are important because they have implicationsfor the immediate responses people make in the contexts in which intergroupthreat elicits these emotions. In addition to the effects the emotions are likelyto have on performance, they may also affect cognitions. Recent research,summarized by Lerner and Tiedens (2007), has indicated that fear and angerlead people to focus on information and events relevant to those particularemotions. That is, fearful people attend to fear-related events and informa-tion, while angry people focus on anger-related events and information. Inaddition, Lerner and Tiedens argued that anger produces a sense of certaintyin one’s ability to function effectively in the future, whereas fear produces asense of uncertainty and pessimism. The uncertainty created by fear leads tomore careful processing of information. In contrast, the certainty produced


by anger leads to heuristic processing of information. Thus, it may be the casethat the fear generated by individual threats leads to pessimistic assessmentsof future intergroup relations. The anger generated by group threats maylead to (overly) optimistic assessments of the in-group’s ability to deal withthese threats. It might also be expected that individual threats would lead tomore attention to stereotype-disconfirming information and other informa-tion regarding out-group threats than would group threats.

These studies and related research (Brewer & Alexander, 2002; Devoset al., 2002; Neuberg & Cottrell, 2002; Stephan & Renfro, 2002) make it clearthat threats play an important role in intergroup relations, but additionalresearch on emotional reactions to intergroup threats is needed. Investiga-tions into moderating variables, the emotions produced by different types ofintergroup threat, and the consequences of these emotional reactions areneeded to further our understanding of reactions to intergroup threat. As welearn more about the causes and consequences of intergroup threats, it maybe possible to design interventions that will reduce some of the negativeemotional, physiological, and behavioral effects of threat.

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