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Wilfrid Laurier University Faculty of Science
October 25, 2016
Canadian Excellence
Dr. Lara Kammrath

Dr. Lara Kammrath

Associate Professor, Psychology

Contact Information

Other Phone: 630-608-3891

Office Hours: On Extended Leave (July 2011-June 2012)
Academic Background

BA, Psychology, University of Chicago
PhD, Social-Personality Psychology, Columbia University
Post-Doctoral Fellow, Social-Organizational Psychology, Columbia Business School

In my research, I investigate social cognitive and personality factors that influence people’s thoughts and behavior within their close relationships, especially in challenging situations, such as when individuals must respond to a person acting antisocially, when they must attempt to sustain costly pro-relational behavior over time, when they must navigate a conflict conversation, or when they must decide how to handle feelings of relationship dissatisfaction.

Additional Information

Peetz, J., & Kammrath, L.K. (in press).  Only because I love you: Why people make and why they break promises in romantic relationships. In Press at the Journal of Personality and Social Psychology.

People make and break promises frequently in interpersonal relationships. In this paper, we investigate the processes leading up to making promises and the processes involved in keeping them. Across four studies, we demonstrated that people who had the most positive relationship feelings and who were most motivated to be responsive to the partner’s needs made bigger promises than other people, but were not any better at keeping them. Instead, promisers’ self-regulation skills, such as trait conscientiousness, predicted the extent to which promises were kept or broken. In a causal test of our hypotheses, participants who were focused on their feelings for their partner promised more, whereas participants who generated a plan of self-regulation followed through more on their promises. Thus, people were making promises for very different reasons (positive relationship feelings, responsiveness motivation) than what made them keep these promises (self-regulation skill). Ironically, then, those who are most motivated to be responsive may be most likely to break their romantic promises, as they are making ambitious commitments they are later unable to keep.


Kammrath, L.K., & Peetz, J. (in revision). The limits of love: Predicting immediate versus sustained caring behaviors in close relationships. In Revision at the Journal of Experimental Social Psychology.

Do the same kinds of processes predict spontaneous acts of kindness and long-term caring behavior in relationships? Three studies examined predictors of immediate behaviors versus delayed, sustained behaviors. Positive feelings toward the relationship partner predicted pro-relational behaviors when the behaviors could be completed in an immediate and fairly short timespan, but not when the behaviors required performance after several days delay (Study 1) or when the behavior required continued self-regulation over a period of a week (Studies 2 and 3). Sustained behavior regulation was better predicted by factors related to self-regulation strength, such as trait conscientiousness, than it was by positive feelings. Study 3 additionally demonstrated that when loving feelings were primed daily, the feelings-behavior link remained strong for sustained behaviors. Together, these studies suggest that within the realm of positive relationship behavior, immediate pro-relational behaviors are more likely to be acts of the heart, whereas delayed, sustained pro-relational behaviors are more likely to be acts of will.


Kammrath, L.K. (in revision). The expected consequences of interpersonal action: How the same relational behaviors mean different things to people with different personality profiles. In Revision at the Journal of Personality and Social Psychology.

People’s knowledge about relational behavior includes if-then behavior schemas for how particular types of behavior, such as acting coldly or acting assertively, will typically impact others. In this paper, it is argued that a person’s own personality configuration of if-then responses in social interactions (Mischel & Shoda, 1995) contributes to that person’s beliefs about the meaning and impact of relational behaviors more generally. Specifically, it is argued that people who experience strong (or weak) responses to behaviors that vary along a particular trait dimension, such as warmth-coldness, will expect others to experience similarly strong (or weak) responses to those same kinds of behaviors.  In three studies, it was demonstrated that people who are high in trait communion expect others to respond more strongly to behaviors that vary in warmth-coldness than do people who are low in trait communion, and that people who are low in trait agency expect others to respond more strongly to behaviors that vary in assertive-unassertiveness than do people who are high in trait agency. Studies 2 and 3 suggested that it was participants’ own if-then personality profiles that accounted, at least in part, for the effects of personality traits on participants’ if-then schemas for relational behavior.


Friesen, C. & Kammrath, L.K. (in revision). What it pays to know about a close other: The value of contextualized “if-then” personality knowledge in close relationships. In revision at Psychological Science.

Past research has debated the benefits of having accurate knowledge about a close other’s personality. However, this research has examined personality knowledge solely in terms of traits. We hypothesize that within close relationships, accurate personality knowledge about “if-then” profiles – a person’s characteristic pattern of responses to situations - may often be highly useful. We provide the first study of if-then accuracy in close relationships, investigating if-then trigger profiles, which describe a person’s unique pattern of reactivity to various potentially aversive interpersonal situations. We developed the If-Then Trigger Profile Questionnaire, consisting of 72 descriptions of potentially bothersome interpersonal behaviors. Participants rated how much each behavior triggered them personally, and how much it might trigger a friend. Findings demonstrated that accurate knowledge about a friend’s if-then trigger profile was associated with reduced feelings of conflict in the relationship, and increased feelings of depth.



Kammrath, L.K., & Scholer, A.A. (under review) The high-maintenance perceiver: How highly agreeable people judge positive and negative relational acts. Manuscript under review.

Although people high in agreeableness have often been shown to be positively biased towards others, four studies provide evidence that agreeableness is associated with extremity effects, not simple positivity effects, in social judgment. Across studies, agreeable participants judged prosocial behaviors more favorably, but antisocial behaviors more unfavorably, than did disagreeable participants. In support of a goal-congruence mechanism, Study 1 showed that communal goals, rather than perceived similarity, mediated the effects, and Studies 2-4 demonstrated that agreeable perceivers were particularly sensitive to communal (vs. agentic) violations. A longitudinal study of real-life impressions supported the laboratory evidence that agreeable people are highly sensitive to both the prosocial and antisocial behavior of others (Study 4). We discuss how the current account complements and extends existing theories of agreeableness.


McCarthy, M., & Kammrath, L.K. (under review). Raising an issue in a relationship: I’ll tell you what’s wrong but only if I think it will help. Manuscript under review.

When we become dissatisfied with the actions of a close partner, we face a decision: voice our concerns or remain silent. Past research suggests degree of dissatisfaction does not differentiate concerns that are voiced from those that are not. Four studies investigated the hypothesis that, because disclosure is risky, outcome expectancies may be more influential than dissatisfaction or issue importance. In each study, participants identified a relational dissatisfaction they were considering disclosing. Expectancies for instrumental outcomes emerged as the sole unique predictor of general voice intentions and behavior. Expectancies for relationship outcomes, however, differentiated between positive and negative voice. Thus, when participants thought voice would solve the problem, they were more likely to speak up. However, when they thought the other person would respond positively to the discussion, they were more likely to voice in a friendly, constructive manner, and less likely to voice in a hostile, destructive manner.


Kammrath, L.K., & Peetz, J. (under review) You promised you’d change: How incremental and entity theorists react to a romantic partner’s change attempts. Manuscript under review.

Research from multiple domains suggests that individuals benefit from having other people in their lives who endorse an incremental mindset, believing in humans’ capacity to change and improve through effort. We hypothesize, however, that people high in incrementalism may have unrealistic expectations about the ease of change, leading them to become frustrated with others who attempt change (change-strivers) with only partial success. In a longitudinal study, change-strivers made promises of change to their romantic partners and attempted to keep those promises over two weeks. Romantic partners who were higher in incrementalism were initially more optimistic that change-strivers would successfully change, but subsequently more angry and distrustful toward change-strivers whose change attempts failed. Furthermore, partners high in incrementalism were more likely to attribute failure to the change-striver’s lack of effort, rather than to the difficulty of the behaviors. The findings highlight circumstances when incremental mindsets may have costs in relationships.


Kammrath, L.K., McCarthy, M., & Friesen, C. (under review).  Flexible versus inflexible assertiveness: The discriminative profiles of extraversion and agreeableness. Manuscript under review.

Higher levels of extraversion and lower levels of agreeableness are both associated with greater assertiveness. Nevertheless, the assertiveness of highly extraverted and highly disagreeable people may differ.  People are characterized not only by their average level of assertiveness, but also, we propose, by the discriminative facility of their assertiveness, that is, how much they adjust their level of assertion to fit the importance of the issue or concern. We hypothesize that highly extraverted and highly disagreeable people manifest similar average levels of assertiveness, but differing degrees of discriminative facility. In Study 1, participants reported the frequency with which they typically confront people who engage in a range of potentially annoying interpersonal behaviors. In Study 2, participants reported the extent that they voiced specific recent relationship dissatisfactions to close others. As predicted, extraversion was associated with high-discriminative assertiveness, whereas disagreeableness was associated with low-discriminative assertiveness.


Ames, D.R., Kammrath, L.K. Suppes, A., & Bolger, N. (2010).  Not so fast: The (not-quite-complete) dissociation between accuracy and confidence in thin slice impressions. Personality and Social Psychology Bulletin, 36, 264-277.

Psychologists and non-psychologists alike have recently been captivated by demonstrations that, on average, perceivers show significant accuracy in their snap judgments of others. Yet beneath mean levels of accuracy lies tremendous variance—some snap judgments are valid, others wrongheaded. An essential question, therefore, is whether people can intuit when their first impressions are accurate. In two new studies of snap impressions, and in new analyses of prior studies featuring impressions based on offices and bedrooms (Gosling, Ko, Mannarelli, & Morris, 2002), we examine links between thin slice accuracy and metacognition. The data reveal that while some perceivers were impressively accurate some of the time, confidence in impressions was uncalibrated with accuracy. Ratings of confidence in a given judgment more closely reflected a person’s general confidence in other judgments than accuracy in the specific instance. Moreover, perceivers generally displayed overconfidence. Implications for work on thin slice judgments are discussed.

Kammrath, L.K., Ames, D.R., & Scholer, A.A. (2007).  Keeping up impressions: Inferential standards for impression change across the Big Five. Journal of Experimental Social Psychology, 43, 450-457.

Not all first impressions have equal longevity. Which kinds of impression have the greatest mobility–downward and upward–over the course of acquaintanceships? In this article, we propose an inferential account of impression maintenance across Big Five trait domains. With data from field and laboratory studies, we provide evidence that positive impressions of agreeableness (A), conscientiousness (C), and emotional stability (ES) are especially vulnerable to small amounts of contrary evidence, whereas positive first impressions of extraversion (E) and openness (O) are more resistant to contrary information. Impressions of E and O demonstrated minimal susceptibility to negativity effects in a longitudinal study of college roommate impressions (Study 1), in a study of perceivers’ implicit theories about different trait domains (Study 2), and in an experimental study of manipulated impression change (Study 3).

Kammrath, L.K. & Dweck, C. (2006).  Voicing conflict: Preferred conflict strategies among incremental and entity and theorists. Personality and Social Psychology Bulletin, 32, 1497-1508.

How individuals choose to handle their feelings during interpersonal conflicts has important consequences for relationship outcomes. Will they voice their dissatisfaction, forgive and forget, or act out with hostile words and deeds? In two studies, we predict and find evidence that people’s implicit theory of personality is an important predictor of conflict behavior following a relationship transgression.  Data from a retrospective study of conflict in dating relationships (Study 1) and a prospective study of daily conflict experiences (Study 2) demonstrated that incremental theorists – who believe personality can change and improve – were highly likely to voice their displeasure with others openly and constructively during conflict.  Conversely, entity theorists – who believe personality is fundamentally fixed – were unlikely to express their feelings of dissatisfaction openly with the targets of their displeasure. Study 2 revealed that this divergence was increasingly pronounced as conflicts increased in severity: the higher the stakes, the stronger the effect.

Kammrath, L.K., Mendoza-Denton, R., & Mischel, W. (2005).  Incorporating if…then… signatures in person perception: Beyond the person-situation dichotomy.  Journal of Personality and Social Psychology, 88, 605-618.

Complex schemas (Kelley, 1972) have been traditionally under-represented in the study of lay causal models.  Nevertheless, complex schemas have particular significance for attribution theory in that they depict dispositions and situations as interactive -- not dichotomous -- causal forces. Three studies find that 1) complex schemas lead perceivers to impart dispositional meaning to stable patterns of situation-behavior variation, and 2) complex schemas are particularly likely to be adopted when the inference task involves motivational attributions.  Study 1 showed that perceivers associated five motivational traits with characteristic and distinctive if…then…  profiles (if situation A, then the person does X, but if situation B, then the person does Y).  Study 2 demonstrated that perceivers used information about a target’s stable if…then… profile to draw conclusions about her motives and traits.   Study 3 suggested that perceivers are more likely to draw on profile information when inferring motivational traits than when inferring behavioral traits. Together, these findings point to the significance of complex motivational schemas that take of account of stable person-situation interactions (she is friendly if A but mean if B) in everyday social explanations.

Ames, D.R., & Kammrath, L.K. (2004).  Mind-reading and metacognition: Narcissism, not actual competence, predicts self-estimated ability. Journal of Non-Verbal Behavior, 28, 187-210.

In this paper, we examine the relationship between people’s actual interpersonal sensitivity (such as their ability to identify deception and to infer intentions and emotions) and their perceptions of their own sensitivity. Like prior scholars, we find the connection is weak or non-existent and that most people overestimate their social judgment and mind-reading skills. Unlike previous work, however, we show new evidence about who misunderstands their sensitivity and why. We find that those who perform the worst in social judgment and mindreading radically overestimate their relative competence. We also find origins of these self-estimates in general narcissistic tendencies toward self-aggrandizement. We discuss evidence from two studies, one involving the Interpersonal Perception Task (the IPT-15) and another focusing on inferences about partners after a faceto-face negotiation exercise. In both cases, actual performance did not predict self-estimated performance but narcissism did.