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2009 American Psychological Association How Self-Affirmation Reduces Defensive Processing of Threatening Health Information: Evidence at the Implicit Level Objective: Self-affirmation reduces defensive responses to threatening health information, but little is
known about the cognitive processes instigated by self-affirmation. This study tested whether self-
affirmation increases responsiveness to threatening health information at the implicit level. Design: In an
experimental study (N ϭ 84), the authors presented high- (coffee drinkers) and low-relevance (noncoffee
drinkers) participants with threatening health information linking caffeine consumption to health prob-
lems. Prior to reading this information, the authors manipulated self-affirmation. Main Outcome
Measures: Participants completed an unobtrusive lexical decision task to measure the accessibility of
threat-related cognitions and reported their perceptions of message quality and intentions to take
precautions. Results: Among high-relevance participants, self-affirmation increased the accessibility of
threat-related cognitions, increased perceptions of message quality, and promoted adaptive behavioral
intentions. Conclusion: The findings suggest that self-affirmation can increase implicit responsiveness to
threatening health information among a target audience, that is, people for whom the health information
is highly relevant.
Keywords: self-affirmation, defensive processing, health risk information, accessibility, persuasion People are often confronted with threatening information telling respond defensively to satisfy it (e.g., they downplay, minimize, or them they live an unhealthy lifestyle that poses a serious risk to avoid threatening health information). The theory further assumes their health. Although people should respond by adopting healthy that people are primarily concerned with their global sense of behaviors or stop risky behaviors, people often persevere with their self-integrity. Consequently, they can also restore self-integrity by unhealthy behaviors (Sherman & Cohen, 2006). For instance, the drawing on alternative sources unrelated to the threat, such as more personally significant a health message is, the more people reflecting on another important value (Steele, 1988). Thus, when are likely to downplay the seriousness of the health risk, question threatened in one domain (e.g., health), people can restore their the accuracy of the threatening information or evidence presented global self-integrity by affirming another important domain (e.g., in the message, and process the information in a biased fashion intelligence). Such a “self-affirmation” restores global self- (e.g., De Wit, Das, & Vet, 2008; Kunda, 1987; Liberman & integrity, thereby reducing the need to respond defensively to the Chaiken, 1992). Although such defensive processing of threaten- ing health information is likely to keep worries at a distance, it can Although more and more studies show that theory-based ma- prevent people from protecting their personal health. Self- nipulations of self-affirmation increase acceptance of threatening affirmation theory (Steele, 1988)—a general theory about how health information among people who normally tend to be defen- people deal with self-threats—may help understand why people sive (e.g., Harris, Mayle, Mabbott, & Napper, 2007; Harris & respond defensively to threatening health information.
Napper, 2005; Sherman, Nelson, & Steele, 2000), there is little According to self-affirmation theory (Steele, 1988), people are direct empirical evidence regarding the cognitive processes that highly motivated to protect and maintain a global sense of self- self-affirmation instigates (Sherman & Cohen, 2006). A better integrity. Threatening information arouses this motive and people insight into these processes is pivotal to increasing our understand-ing of the processes that potentially mediate self-affirmation ef-fects as well as their consequences for the design of health infor- Guido M. van Koningsbruggen, Department of Social and Organiza- mation. Most pressing is the issue of the origins and consequences tional Psychology, Utrecht University, The Netherlands; Enny Das, De- of defensive processing at the implicit level: What makes people partment of Communication Science, VU University Amsterdam, The “turn off” from threatening health information, and is it true that Netherlands; David R. Roskos-Ewoldsen, School of Communication, The self-affirmation makes people “turn on” to threatening health in- formation again? Implicit processes are important to understand Correspondence concerning this article should be addressed to Guido M.
because they influence both how information is processed (Arpan, van Koningsbruggen, Department of Social and Organizational Psychol-ogy, Utrecht University, PO Box 80140, 3508 TC Utrecht, The Nether- Rhodes, & Roskos-Ewoldsen, 2007) and subsequent behavior lands. E-mail: [email protected] (Olson & Fazio, 2009). The present study provides a first pub- VAN KONINGSBRUGGEN, DAS, AND ROSKOS-EWOLDSEN lished test of the effect of self-affirmation on people’s implicit of the threat into the self-system (Sherman & Cohen, 2006). Thus, responsiveness to threatening health information by using an im- self-affirmation should make it easier to encode threatening as- plicit, unobtrusive measure of information accessibility that pro- pects of health information because these aspects no longer pose a vides more insight into the cognitive processes instigated by self- threat to people’s self-integrity. Because information that is better encoded should be easier to retrieve from memory (i.e., moreaccessible; Carlston & Smith, 1996; Higgins, 1996), we measured Self-Affirmation and Responses to Health Information the accessibility of threat-related cognitions with an unobtrusivelexical decision task in the present study. When self-affirmation Self-affirmation can increase attention to and acceptance of promotes responsiveness to health information at the implicit level, threatening health messages, increase perceptions of personal risk, it should increase the accessibility of threat-related cognitions.
strengthen intentions to take precautions, and promote behavior In the present study, we tested this assumption employing the change regarding various health risks, such as smoking (Harris et “caffeine consumption paradigm” that has been frequently used in al., 2007), excessive caffeine consumption (Reed & Aspinwall, previous research on defensive processing of health information 1998; Sherman et al., 2000), alcohol consumption (Harris & Nap- (e.g., see Kunda, 1987; Liberman & Chaiken, 1992; Sherman et per, 2005), unsafe sex (Sherman et al., 2000), insufficient fruit and al., 2000). Moreover, because previous studies that used this vegetable consumption (Epton & Harris, 2008), and Type 2 dia- paradigm provided contradictory evidence regarding the impact of betes (van Koningsbruggen & Das, in press). These effects have self-affirmation on intentions (Reed & Aspinwall, 1998; Sherman remained stable over a period of 1 month (Harris & Napper, 2005).
et al., 2000), we explicitly assessed intentions to take precautions Most studies focus on explicit persuasive outcomes (e.g., atti- and perceptions of health message quality. In doing so, we meet tudes, intentions); less is known about the cognitive processes the call for delineating how cognitive processes influence health instigated by self-affirmation in response to threatening health self-regulatory efforts (Williams, Wasserman, & Lotto, 2003).
information. To illustrate, Sherman et al. (2000) had coffee drink-ers and noncoffee drinkers respond to information linking caffeine consumption to severe health problems. Typically, coffee drinkersrespond defensively, with the result that they accept such infor- Following previous research (e.g., Sherman et al., 2000), we mation to a lesser extent than noncoffee drinkers (e.g., Kunda, recruited high-relevance (coffee drinkers) and low-relevance (non- 1987). Self-affirmation reduced defensive responses among high- coffee drinkers) participants and presented them with health infor- relevance participants: Self-affirmed coffee drinkers were more mation linking caffeine consumption to severe health problems.
likely to accept that caffeine consumption was linked to health Prior to reading this information, we manipulated self-affirmation problems and reported greater intentions to take precautions than by allowing participants to affirm a value that was either person- coffee drinkers who had not self-affirmed. Using a similar para- ally important (self-affirmation) or unimportant (no affirmation) to digm, self-affirmation made high-relevance participants read risk- them. All participants then completed an unobtrusive lexical de- confirming information earlier than risk-neutral or risk- cision task to assess the accessibility of threat-related cognitions.
disconfirming information (Reed & Aspinwall, 1998). However, Subsequently, they reported their perceptions of message quality contrasting previous findings, self-affirmed high-relevance partic- and their intentions to take precautions. We predicted that among ipants reported lower intentions to reduce their caffeine consump- high-relevance participants (coffee drinkers), relative to low- tion than their nonaffirmed counterparts.
relevance participants (noncoffee drinkers), self-affirmation would One recent study reported more direct evidence regarding the increase accessibility of threat-related cognitions, perceptions of cognitive processes instigated by self-affirmation in response to message quality, and intentions to reduce caffeine consumption.
threatening health information by drawing on dual process modelsof persuasion (e.g., Petty & Cacioppo, 1986). When self- affirmation reduces defensive processing, people should differen-tiate between weak and strong arguments in a message and rec- ognize the merits and demerits of these arguments (Petty & The hypotheses were tested in a 2 (relevance: coffee drinker vs.
Cacioppo, 1986). Consistent with this, self-affirmation made peo- noncoffee drinker) ϫ 2 (self-affirmation status: nonaffirmed vs.
ple more sensitive to the quality of the arguments in a health self-affirmed) between-participants factorial design. A total of 84 message (van Koningsbruggen & Das, 2009). These findings sug- university students participated in the experiment, of which 20 gest that self-affirmation gives people the resources to deal with were men and 64 were women with a mean age of 23.62 years threatening health information, thus enabling them to process this (SD ϭ 3.66). As compensation for their participation, participants information in a more open-minded fashion.
could take part in a lottery in which they could win gift vouchers Most pressing is the absence of research on self-affirmation in the area of less controlled, automatic cognitive responses to threat-ening health information. Because many self-regulatory processes occur automatically and outside awareness (e.g., Bargh & Char-trand, 1999), it is important to test whether the proposed resource Participants were informed that they would participate in several function of self-affirmation may also extend to this area, and separate computerized studies: one about consumption patterns whether it increases responsiveness to threatening health informa- concerning several beverages, one about values, one assessing tion at the implicit level. Theoretically, self-affirmation is pre- student opinions of scientific articles, and the other about word sumed to diminish self-integrity concerns and stimulate integration SELF-AFFIRMATION AND THREAT ACCESSIBILITY After the introduction, participants were presented disease, restless, sick; all single words in Dutch), the remaining with several questions designed to identify their coffee drinking items reflected control words (e.g., apartment, mechanic, motor- behavior (e.g., coffee drinker ϭ yes/no; if yes, whether they way). The threat-related words were selected on the basis of a pilot consumed regular or decaffeinated coffee, etc.). To bolster our study in which participants (n ϭ 41, not taking part in the actual cover story, we asked similar questions about several other bev- experiment) rated on a 7-point scale (1 ϭ not at all, 7 ϭ very erages. The sample consisted of 47 coffee drinkers and 37 non- much) to what extent these and 10 other words pertained directly coffee drinkers. Participants then continued with the “value study” to health problems related to caffeine consumption. The 5 words that contained the manipulation of self-affirmation.
selected were the ones rated highest on this measure (M ϭ 5.15, SD ϭ 1.99). All words were matched on word length across word affirmation was based on a well-established procedure (e.g., Harris type categories, randomly presented, and preceded by four practice & Napper, 2005). Participants were randomly assigned to either the self-affirmed status condition (n ϭ 40) or the nonaffirmed status condition (n ϭ 44). They were first presented with the six tions of message quality, they responded to the statement, “The values of the Allport–Vernon–Lindzey Study of Values (Allport, evidence linking caffeine consumption and health problems is Vernon, & Lindzey, 1960). The values listed were science, busi- reliable” (1 ϭ strongly disagree, 7 ϭ strongly agree). Higher ness, art, social, politics, and religion. In the self-affirmed status scores indicate higher perceptions of message quality.
condition, participants were asked to choose their most important Intentions to reduce caffeine consumption. value and to write about why it was important to them and to two statements that examined their intentions to reduce their describe a specific occasion when it had been particularly impor- caffeine consumption on a 7-point scale (based on Block & Wil- tant. In the nonaffirmed status condition, they were asked to liams, 2002; “I intend to cut down my caffeine consumption” and choose their least important value and to write about why the value “I am convinced that I will reduce the amount of caffeine I might be important to the average student.
consume”; 1 ϭ strongly disagree, 7 ϭ strongly agree; r ϭ .79, p Ͻ After the manipulation of self-affirmation, .001). Higher scores indicate greater intentions to reduce caffeine participants read a fictitious article titled “The Effects of Caffeine on Health,” which was supposedly published in the Journal ofMedicine (based on Block & Williams, 2002). The first part of thearticle presented several examples of products containing caffeine.
It was stressed that the greatest part of people’s caffeine intakecould be related to their coffee consumption. The second part Accessibility of Threat-Related Cognitions described possible health problems related to caffeine consump-tion (e.g., insomnia, restlessness, high blood pressure, cardiovas- The computer recorded both the response (i.e., word or non- cular disease). Moreover, it was stated that research suggested that word) and RT (in ms) per presented item for each participant.
people who consume high doses of caffeine, for example, coffee Incorrect responses were excluded from the analysis (2.86% across drinkers, are more likely to suffer a heart attack or a stroke. After the experimental trials, which were evenly distributed across con- participants read the health message, they were asked to participate ditions). The harmonic means of RT (Ratcliff, 1993) for threat- in the study on word recognition (i.e., the lexical decision task).
related words and control words were subjected to a 2 (relevance: Participants then completed the perceived message quality and coffee drinker vs. noncoffee drinker) ϫ 2 (self-affirmation status: intention measures, were probed for suspicions about the purpose nonaffirmed vs. self-affirmed) ϫ 2 (word type: threat-related vs.
of the study, and then were extensively debriefed. None of the control) mixed design analysis of variance (ANOVA) with re- participants guessed any aspect of the true purpose of the study, peated measures on the third factor. The analysis revealed a main and none of them reported a suspicion that the studies were related.
effect of word type, F(1, 80) ϭ 17.49, p Ͻ .001, ␩2 ϭ .18.
Participants responded faster to threat-related words (M ϭ 775 ms) than to control words (M ϭ 837 ms). In addition, the analysisrevealed the predicted interaction effect between relevance, self- Accessibility of threat-related cognitions. affirmation, and word type, F(1, 80) ϭ 7.79, p ϭ .007, ␩2 ϭ .09.
informed that a sequence of words would appear individually in Simple effects analysis indicated that among the coffee drinkers, the center of the screen. They were asked to decide as quickly and self-affirmed participants responded faster to threat-related words accurately as possible whether the presented word was an existing than nonaffirmed participants, F(1, 80) ϭ 4.69, p ϭ .033, ␩2 ϭ Dutch word or a nonword by pushing either the A (for existing .06. No effect of self-affirmation was found among the noncoffee words) or the L (for nonwords) key on the keyboard. Each trial first drinkers, F Ͻ 1. Also, no self-affirmation effects occurred on RT presented a fixation point in the center of the screen that was for control words: for coffee drinkers, F Ͻ 1; for noncoffee replaced by the stimulus after 1 s. The next trial was initiated 500 drinkers, F(1, 80) ϭ 1.19, ns. Relevant means are displayed in ms after participants pressed one of the keys. In total, participants responded to 40 words, consisting of 20 existing Dutch words and20 nonwords. In reality, we were interested in reaction times (RT)to existing target words between conditions. Among the existing 1 It should be noted that the nonthreat words were not equivalent in words, 5 were threat-related target words from the health message frequency of use to those of the threat words. Because our key comparisons participants had just read, pertaining to the adverse health prob- are within-word between-conditions, this issue does not affect the results lems of caffeine consumption (blood pressure, heart attack, heart VAN KONINGSBRUGGEN, DAS, AND ROSKOS-EWOLDSEN to perceived message quality among self-affirmed coffee drinkers.
Mean Harmonic Mean Reaction Time (ms) as a Function of Thus, participants with faster response latencies to threat-related Relevance, Self-Affirmation Status Condition, words reported higher perceptions of quality of the message link- ing caffeine consumption and health problems. This finding, inconjunction with the results on the lexical decision task, suggests that increased accessibility of threat-related cognitions is related to less defensive responding to threatening health information.
Nonaffirmed Self-affirmed Nonaffirmed Self-affirmed The present study provided a first published test of the impact of self-affirmation on people’s implicit responsiveness to threatening Within rows, means with different subscripts differ significantly health information. High-relevance (coffee drinkers) and low- relevance (noncoffee drinkers) participants were either self-affirmed or not prior to reading information linking caffeine con- sumption to severe health problems. The results revealed a highlyconsistent pattern across implicit and explicit measures. As pre- A 2 (relevance) ϫ 2 (self-affirmation status) ANOVA on per- dicted, self-affirmation increased high-relevance participants’ ac- ceived message quality revealed a significant interaction between cessibility of threat-related cognitions, positively affected percep- relevance and self-affirmation, F(1, 80) ϭ 7.04, p ϭ .01, ␩2 ϭ .08.
tions of message quality, and increased intentions to take Simple effects analysis revealed that among the coffee drinkers, self-affirmed participants reported higher perceptions of message Consistent with previous research, we showed that self- quality (M ϭ 4.56, SD ϭ 0.64) than nonaffirmed participants (M ϭ affirmation reduces defensiveness toward threatening health infor- 3.90, SD ϭ 0.91), F(1, 80) ϭ 5.60, p ϭ .02, ␩2 ϭ .07. No effect mation, and promotes adaptive behavioral intentions among people of self-affirmation was found among the noncoffee drinkers (Mself- for whom the information is highly relevant (e.g., Harris & Nap- per, 2005; Sherman et al., 2000). In addition, the present findings affirmed ϭ 1.20), F(1, 80) ϭ 2.15, ns.
are the first to demonstrate that the beneficial effects of self-affirmation are not limited to changes in explicit variables related Intentions to Reduce Caffeine Consumption to persuasive outcomes but extend to the realm of less controlled,automatic cognitive responses to threatening health information.
A 2 (relevance) ϫ 2 (self-affirmation status) ANOVA on inten- Herewith, this study provides more insight into the cognitive tions to reduce caffeine consumption revealed a significant inter- processes instigated by self-affirmation. At this point, little is action between relevance and self-affirmation, F(1, 80) ϭ 6.03, known about implicit processes related to threatening information p ϭ .016, ␩2 ϭ .07. Simple effects analysis revealed that among (Glaser & Banaji, 1999; Roskos-Ewoldsen, Yu, & Rhodes, 2004).
the coffee drinkers, self-affirmed participants reported greater in- Demonstrating a link between the accessibility of threatening tentions to reduce their caffeine consumption (M ϭ 3.02, SD ϭ information and perceptions of message quality when people are 1.73) than nonaffirmed participants (M ϭ 2.10, SD ϭ 0.97), F(1, self-affirmed sheds further light on the dynamic relationship be- 80) ϭ 5.42, p ϭ .022, ␩p2 ϭ .06. No effect of self-affirmation was tween threat and message processing.
found among the noncoffee drinkers (M Although there is some evidence that self-affirmation increases extensive, careful processing of threatening health information on a conscious, explicit level (van Koningsbruggen & Das, 2009), thepresent study suggests that when self-affirmation diminishes con- Relationship Between Implicit and Explicit Measures cerns about self-integrity, threatening health information becomes Following Baron and Kenny (1986), we tested whether the easier to retrieve from memory. This also fits nicely with and difference in RT to threat-related words mediated the impact of supplements previous research showing that self-affirmation self-affirmation on perceived message quality or intentions among makes people read risk-confirming information earlier (Reed & high-relevance participants (controlling for overall speed of re- Aspinwall, 1998). Because information that is more accessible will sponding; cf. Rhodes, Roskos-Ewoldsen, Edison, & Bradford, be more likely encoded and recalled (Carlston & Smith, 1996; 2008). Self-affirmation predicted RT to threat-related words, B ϭ Higgins, 1996), the present results are consistent with the idea that Ϫ48.09, t(44) ϭ Ϫ2.66, p ϭ .011, and also perceived message self-affirmation stimulates integration of the threat into the self- quality, B ϭ 0.34, t(44) ϭ 2.97, p ϭ .005, and intentions, B ϭ system (Sherman & Cohen, 2006). Consequently, because the 0.47, t(44) ϭ 2.14, p ϭ .038. However, RT to threat-relatedwords did not significantly predict perceived message quality ( p ϭ 2 We also tested whether perceived message quality mediated the effect .38) or intentions ( p ϭ .19). Thus, no further analyses were of self-affirmation on intentions among high-relevance participants. Self- conducted because not all conditions for mediation were met.2 affirmation predicted perceived message quality (B ϭ 0.34, t ϭ 2.97, p ϭ Finally, we performed partial correlation analyses between RT .005), but message quality did not predict intentions ( p ϭ .20). Consistent to threat-related words and the perceived message quality and with the notion of compatibility of levels of measurement (Ajzen, 1988), intention measures among high-relevance participants. As can be general beliefs about message quality did not predict specific behavioral seen in Table 2, RT to threat-related words was negatively related intentions to reduce caffeine consumption.
SELF-AFFIRMATION AND THREAT ACCESSIBILITY message quality, suggesting that more systematic information pro- Partial Correlations Between Reaction Times to cessing at the explicit level fostered by self-affirmation goes Threat-Related Words and Perceived Message Quality and hand-in-hand with greater responsiveness at the implicit level.
Intentions for High-Relevance Participants The present findings also add to the growing evidence that self-affirmation can promote intentions to take precautions. Al- though we did not assess whether participants actually translatedtheir intentions into actions, recent findings suggest that self- affirmation can promote behavior change. One study that exam- ined screening behavior demonstrated that self-affirmation in- creased risk test taking among people for whom the health information was highly relevant (van Koningsbruggen & Das, in press), and another study showed that self-affirmation increased fruit and vegetable consumption (Epton & Harris, 2008). However, a Controlling for overall speed of responding.
future studies are needed to extend these findings to other behav-iors. In addition, although the accessibility of the threateninginformation was not related to behavioral intentions, this is con- threatening aspects of the health information no longer pose a sistent with a broad array of research demonstrating that construct threat to people’s self-integrity, it should reduce the need, for and attitude accessibility play a greater role in the prediction of example, to derogate the health information. Consistent with this, spontaneous behaviors rather than deliberative behavior or behav- we found that the more accessible threat-related cognitions were ioral intentions (Olson & Fazio, 2009). Testing the impact of for self-affirmed coffee drinkers, the more enhanced were their self-affirmation on spontaneous health behaviors constitutes an perceptions of quality of the message linking caffeine consumption important agenda for future studies.
In conclusion, this study provided a first test of the impact of Although the accessibility of threat-related cognitions did not self-affirmation on implicit responsiveness to threatening health mediate the effects of self-affirmation on perceptions of message information. Although several studies have demonstrated that self- quality and intentions among high-relevance participants, we did affirmation can reduce defensive responses at the explicit level, find a significant relationship between the accessibility of threat- insight into the cognitive processes instigated by self-affirmation related cognitions and perceived message quality among self- tended to be limited (Sherman & Cohen, 2006). The present affirmed, high-relevance participants. This finding suggests that findings represent a step forward in this area: Self-affirmation implicit responsiveness to threatening health information is related promotes accessibility of threatening health information.
to decreased defensive responding at the explicit level. In addition,the finding is in line with previous research showing that global cognitions may be related to specific cognitions, particularly when Ajzen, I. (1988). Attitudes, personality, and behavior. Chicago: Dorsey.
they are highly accessible (Fazio, 1995). In the present study, it is Allport, G. W., Vernon, P. E., & Lindzey, G. (1960). Study of values (3rd likely that we could not establish mediation because we measured construct accessibility rather than attitude accessibility (Fazio, Arpan, L., Rhodes, N., & Roskos-Ewoldsen, D. R. (2007). Attitude acces- 1995; see also, e.g., Houston & Fazio, 1989), the former being a sibility: Theory, methods and future directions. In D. R. Roskos- less likely candidate in predicting specific attitudes. Furthermore, Ewoldsen & J. L. Monahan (Eds.), Communication and social cogni- some features of the present study seem to have limited our ability tion: Theories and methods. Mahwah, NJ: Erlbaum.
to detect these effects; we assessed perceived message quality with Bargh, J. A., & Chartrand, T. L. (1999). The unbearable automaticity of only one item, and our data may have limited statistical power to being. American Psychologist, 54, 462– 479.
detect mediation (Fritz & MacKinnon, 2007). Future studies Baron, R. M., & Kenny, D. A. (1986). The moderator–mediator variable should take these limitations into account when further examining distinction in social psychological research: Conceptual, strategic, andstatistical considerations. Journal of Personality and Social Psychology, the relation between accessibility of threat-related cognitions and variables involved in the behavior change process. This would also Block, L. G., & Williams, P. (2002). Undoing the effects of seizing and provide a better test of whether the change in implicit responsive- freezing: Decreasing defensive processing of personally relevant mes- ness observed in the present study is indicative of a mechanism sages. Journal of Applied Social Psychology, 32, 803– 833.
underlying the obtained self-affirmation effects on the explicit Carlston, D. E., & Smith, E. R. (1996). Principles of mental representation.
measures, or indicative of a consequence of more open-minded In E. T. Higgins & A. W. Kruglanski (Eds.), Social psychology: Hand- information processing fostered by self-affirmation.
book of basic principles (pp. 184 –210). New York: Guilford Press.
Related to this issue is the possibility that self-affirmed partic- De Wit, J. B. F., Das, E., & Vet, R. (2008). What works best: Objective ipants may have spent more time reading the health information statistics or a personal testimonial? An assessment of the persuasive and, as a result of greater priming, the threatening aspects of the effects of different types of message evidence on risk perception. HealthPsychology, 27, 110 –115.
health information became easier to retrieve from memory. Al- Epton, T., & Harris, P. R. (2008). Self-affirmation promotes health behav- though the present study did not record how long participants spent ior change. Health Psychology, 27, 746 –752.
reading the health information, recent research suggests that self- Fazio, R. H. (1995). Attitudes as object-evaluation associations: Determi- affirmation can increase extensive, careful information processing nants, consequences, and correlates of attitude accessibility. In R. E.
(van Koningsbruggen & Das, 2009). Self-affirmed participants’ Petty & J. A. Krosnick (Eds.), Attitude strength: Antecedents and con- careful scrutiny of the message should influence judgments of sequences (pp. 247–282). Hillsdale, NJ: Erlbaum.
VAN KONINGSBRUGGEN, DAS, AND ROSKOS-EWOLDSEN Fritz, M. S., & MacKinnon, D. P. (2007). Required sample size to detect Ratcliff, R. (1993). Methods for dealing with reaction time outliers. Psy- the mediated effect. Psychological Science, 18, 233–239.
chological Bulletin, 114, 510 –532.
Glaser, J., & Banaji, M. R. (1999). When fair is foul and foul is fair: Reed, M. B., & Aspinwall, L. G. (1998). Self-affirmation reduces biased Reverse priming in automatic evaluation. Journal of Personality and processing of health-risk information. Motivation and Emotion, 22, Social Psychology, 77, 669 – 687.
Harris, P. R., Mayle, K., Mabbott, L., & Napper, L. (2007). Self- Rhodes, N., Roskos-Ewoldsen, D. R., Edison, A., & Bradford, M. B.
affirmation reduces smokers’ defensiveness to graphic on-pack cigarette (2008). Attitude and norm accessibility affect processing of anti- warning labels. Health Psychology, 26, 437– 446.
smoking messages. Health Psychology, 27, 224 –232.
Harris, P. R., & Napper, L. (2005). Self-affirmation and the biased pro- Roskos-Ewoldsen, D. R., Yu, H. J., & Rhodes, N. (2004). Fear appeal cessing of threatening health-risk information. Personality and Social messages affect accessibility of attitudes toward the threat and adaptive Psychology Bulletin, 31, 1250 –1263.
behaviors. Communication Monographs, 71, 49 – 69.
Higgins, E. T. (1996). Knowledge activation: Accessibility, applicability, Sherman, D. K., & Cohen, G. L. (2006). The psychology of self-defense: and salience. In E. T. Higgins & A. W. Kruglanski (Eds.), Social Self-affirmation theory. In M. P. Zanna (Ed.), Advances in experimental psychology: Handbook of basic principles (pp. 133–168). New York: social psychology (Vol. 38, pp. 183–242). San Diego, CA: Academic Houston, D. A., & Fazio, R. H. (1989). Biased processing as a function of Sherman, D. K., Nelson, L. D., & Steele, C. M. (2000). Do messages about attitude accessibility: Making objective judgments subjectively. Social health risks threaten the self? Increasing the acceptance of threatening health messages via self-affirmation. Personality and Social Psychology Kunda, Z. (1987). Motivated inference: Self-serving generation and eval- uation of causal theories. Journal of Personality and Social Psychology, Steele, C. M. (1988). The psychology of self-affirmation: Sustaining the integrity of the self. In L. Berkowitz (Ed.), Advances in experimental Liberman, A., & Chaiken, S. (1992). Defensive processing of personally social psychology (Vol. 21, pp. 261–302). New York: Academic Press.
relevant health messages. Personality and Social Psychology Bulletin, van Koningsbruggen, G. M., & Das, E. (2009). When self-affirmation decreases extensive processing of threatening information: The moder- Olson, M. A., & Fazio, R. H. (2009). Implicit and explicit measures of ating role of self-threat level. Manuscript in preparation.
attitudes: The perspective of the mode model. In R. E. Petty, R. H. Fazio, van Koningsbruggen, G. M., & Das, E. (in press). Don’t derogate this & P. Brin˜ol (Eds.), Attitudes: Insights from the new implicit measures message! Self-affirmation promotes online Type 2 diabetes risk test (pp. 19 – 63). New York: Psychology Press.
Petty, R. E., & Cacioppo, J. T. (1986). The elaboration likelihood model of Williams, P. G., Wasserman, M. S., & Lotto, A. J. (2003). Individual persuasion. In L. Berkowitz (Ed.), Advances in experimental social differences in self-assessed health: An information-processing investi- psychology (Vol. 19, pp. 123–205). San Diego, CA: Academic Press.
gation of health and illness cognition. Health Psychology, 22, 3–11.

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