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What fuels passion? An integrative review of competing theories of romantic passion



In an integrative review, we examine four theories and models of romantic passion to determine what causes feelings of romantic passion. Although a growing consensus has emerged for the definition of romantic passion, we suggest that this is largely not the case for the source of romantic passion. We outline how four different perspectives—Limerence Theory, the Rate of Change in Intimacy Model, the Self‐Expansion Model, and the Triangular Theory of Love—propose four different potential sources of romantic passion and review empirical support in favor and against each. For each of these perspectives, we additionally outline the predicted trajectory of passion that follows from each theorized source of passion, as well as each perspective's view on the ability for passion to be controlled and up‐regulated. In identifying ways in which these theories and models offer conflicting predictions about the source of romantic passion, this review points to ways in which a more comprehensive model may be developed that integrates across these four perspectives.
Received: 15 May 2020
Revised: 27 April 2021
Accepted: 14 May 2021
DOI: 10.1111/spc3.12629
What fuels passion? An integrative review of
competing theories of romantic passion
Kathleen L. Carswell
|Emily A. Impett
Department of Psychology, Durham
University, Durham, UK
Department of Psychology, University of
Toronto Mississauga, Mississauga, Ontario,
Kathleen L. Carswell, Department of
Psychology, Durham University, Upper
Mountjoy, South Rd, Durham DH1 3LE, UK.
In an integrative review, we examine four theories and
models of romantic passion to determine what causes
feelings of romantic passion. Although a growing consensus
has emerged for the definition of romantic passion, we
suggest that this is largely not the case for the source of
romantic passion. We outline how four different
perspectives—Limerence Theory, the Rate of Change in
Intimacy Model, the SelfExpansion Model, and the Trian-
gular Theory of Love—propose four different potential
sources of romantic passion and review empirical support
in favor and against each. For each of these perspectives,
we additionally outline the predicted trajectory of passion
that follows from each theorized source of passion, as well
as each perspective's view on the ability for passion to be
controlled and upregulated. In identifying ways in which
these theories and models offer conflicting predictions
about the source of romantic passion, this review points to
ways in which a more comprehensive model may be
developed that integrates across these four perspectives.
Popular culture paints an image of romantic passion as a mysterious and uncontrollable desire that ignites instantly
between unwitting victims. Struck by cupid's arrow, the prince is overcome by the beauty of a princess; the
romantic comedy heroine helplessly succumbs to her irrepressible attraction for the insufferable, but strangely
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and
reproduction in any medium, provided the original work is properly cited.
© 2021 The Authors. Social and Personality Psychology Compass published by John Wiley & Sons Ltd.
Soc Personal Psychol Compass. 2021;e12629.
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appealing male lead; and on the flip side, the reality dating show star laments that “there just wasn’t that spark.”
Research over the past several decades has begun to converge on a definition of romantic passion, however, a
consensus has yet to emerge on what ultimately fuels and snuffs out such illusive passionate feelings. To help
illuminate how passion develops, dissipates, and how it might be revived, we review four different theories and
models of romantic passion from relationship science to better understand the source of this soughtafter, but
hardtoattain state (Carswell & Finkel, 2018; Carswell et al., 2019; Hatfield & Rapson, 2006; Simpson et al., 1986).
Given that these models and theories have largely been proposed and investigated independently, we aim to
highlight how these different perspectives diverge in their predictions and might be better integrated into a more
comprehensive model of romantic passion.
The most common definition of romantic passion (also referred to as passionate love) is “an intense longing for
union with the other” (Hatfield & Walster, 1978, p. 9). It is an intense psychological state often characterized by
powerful emotions—elation or ecstasy when feelings are reciprocated, and anxiety or despair when feelings are
unreciprocated—as well as a sense of strong motivational wanting of another, sometimes to the point of obsession
(Aron et al., 2005; Graham, 2011; Hatfield & Walster, 1978; Sternberg, 1986; Tennov, 1979). The most widely used
measure of passion, the Passionate Love Scale (Hatfield & Sprecher, 1986), delineates cognitive (e.g., “intrusive
thinking or preoccupation with the partner”), affective (e.g., “attraction to the partner, especially sexual attraction”)
and behavioral components (e.g., “maintaining physical closeness”). Tennov (1979) similarly describes a particularly
intense form of romantic passion, coined “limerence,” which includes motivational and affective properties of
romantic yearning and a desire for one's romantic feelings to be reciprocated. For instance, among the basic
components of limerence are intrusive thinking about the other, longing for romantic reciprocation, an aching in the
center of the chest when reciprocation is uncertain, a feeling of buoyancy or elation when reciprocation is achieved,
and an inability to feel limerent for more than one person at a time.
Romantic passion differs from other affectladen aspects of relationship quality such as intimacy. Whereas
intimacy represents feelings of closeness and connection with another person, romantic passion is a motivational
desire for such intimacy. In support of this motivational aspect of romantic passion, neuroimaging studies have
demonstrated that romantic passion is associated with activation in brain regions associated with motivation and
addiction (Acevedo et al., 2011; Aron et al., 2005; Bartels & Zeki, 2000; Fisher et al., 2002,2005,2016). The
Passionate Love Scale also generally factors separately from assessments of closeness, intimacy, and companionate
or friendshipbased love in psychometric examinations (Aron & Westbay, 1996; Fehr, 1994; Hendrick & Hendrick,
1989; Sprecher & Regan, 1998). Indeed, in the extensive history of attempts to define the word “love” and its
different forms (see Hatfield et al., 2012 and Reis & Aron, 2008 for reviews), scholars have long sought to
distinguish between passionate (or more romantic) forms of love and companionate (or friendshipbased) love. For
example, in the Triangular Theory of Love, passionate love (which Sternberg, 1986 terms “infatuation”) consists of
passion, but does not necessarily promise intimacy or commitment, whereas companionate love offers intimacy and
commitment, but not passion (Hatfield et al., 2012; Sternberg, 1986).
Although romantic passion is primarily conceived of as a longing for union with a romantic partner in the
sense of a desire for emotional union or intimacy, it also often includes a desire for sexual union. Although sexual
desire is strongly correlated with romantic passion, particularly in modern, Western cultures (see Hatfield
et al., 2012 for a review), it is not necessary or sufficient to feel sexual desire to experience passion. Sexual desire
on its own, for example, is more closely tied to gonadal estrogens and androgens, whereas romantic passion is
more closely tied to the “reward” or dopaminergic system of the brain (Aron et al., 2005; Bartels & Zeki, 2000;
Diamond, 2003,2004; Fisher, 1998). Individuals can feel sexual desire for individuals with whom they do not
passionately love (Meyers & Berscheid, 1997). Less commonly, individuals may also experience feelings of
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romantic passion for an individual in the absence of sexual desire (Tennov, 1979). This is often the case among
children prior to puberty (Hatfield et al.,1988) and individuals who are romantically asexual (i.e., individuals who
report experiencing romantic attraction, but not sexual attraction; Bulmer & Izuma, 2018). Thus, although sexual
desire is a strong correlate of romantic passion, particularly in established relationships, it represents just one
component of romantic passion.
Passionate love is experienced with similar frequency and intensity across cultures; however, it is not equally
valued (see Hatfield & Rapson, 2006 and Hatfield et al., 2007,2016 for reviews). Historically and in more collec-
tivistic cultures, romantic passion has been viewed as dangerous and disruptive to collective interests, pulling in-
dividuals away from their family structures or group (Hatfield et al., 2007). Nevertheless, with the growing spread
of westernization leading to greater emphasis on the individual over the collective, as well as greater emphasis on
the individual to select with whom or whether they wish to enter a romantic relationship, romantic passion has
become increasingly valued and the basis of decisions to enter or exit romantic relationships in nearly all cultures
(Hatfield & Rapson, 2006). Given that people around the world are making important, lifechanging relationship
decisions on the basis of romantic passion (or lack thereof), it is critical to better understand its source(s).
Understanding how these feelings or motivations are formed is critical to understanding how one might control
feelings of passion and summon them when desired.
Whereas a growing consensus is emerging on the definition of passion—a strong motivational desire for union with
a romantic partner—there is considerably less agreement about what is theorized to fuel this desire. In this review,
we focus on four major theories or models, outlined in Table 1, that have attempted to explain what causes feelings
of romantic passion: Limerence Theory (Tennov, 1979), the Rate of Change in Intimacy Model (Baumeister &
Bratslavsky, 1999), the SelfExpansion Model (Aron & Aron, 1986), and the Triangular Theory Love (Sternberg,
1986). Although all four of these theories and models predict passion to peak early on in a relationship and steadily
decline over time, the hypothesized source of this initial rise, dissipation, and possible recovery differs across
theories. We summarize each of these theories and models, including their hypothesized source and trajectory of
romantic passion, how passion might be “upregulated” (i.e., intentionally increased), and evidence for and against
each perspective, before highlighting their similarities and differences.
Limerence Theory
Limerence Theory is one of the oldest theories on romantic passion, evolving out of Tennov's (1979) personal,
qualitative interviews in her clinical practice. Thus, in contrast to the other theories reviewed here, which primarily
emerged from quantitative research in social psychology, this theory is rooted more heavily in qualitative research
in clinical psychology. According to Limerence Theory, the primary source of passionate feelings, cognitions, and
behaviors is uncertainty over reciprocated romantic interest.
Source and trajectory of passion
Limerence—an intense form of romantic passion characterized by obsessive, intrusive thoughts about a potential
romantic partner—initially develops after a person admires and/or is physically attracted to another person for
whom they believe there is some hint of possible reciprocity. Uncertainty and difficulty in obtaining that individual's
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TABLE 1Summary of passion theories/models
Source of
passion Trajectory Controllability
Recommendations for upregulation
in longterm relationships
Limerence Theory
(Tennov, 1979)
Uncertainty of
Passion declines over time as certainty
is reached over the existence of
reciprocity or a lack of returned
Low; Individuals need to “recognize that
limerence is basically involuntary. Love
vows reflect intense feeling and total
sincerity, but there is no way that they
can be made to stick when feelings
change.” (Tennov, 1979, p. 262, italics in
Rate of Change in
Intimacy Model
(Baumeister &
Bratslavsky, 1999)
Rapid increases
in intimacy
Passion declines over time as limits of
intimacy are met and rises in
intimacy slow.
Moderate; “As a derivative function,
passion could respond to local changes
in intimacy, and so anything that
stimulates a temporary increase (or
even the appearance of an increase) in
intimacy may help ignite passion.”
(Baumeister & Bratslavsky, 1999, p. 60)
Ration intimacy; engage in reductions of
intimacy (e.g., physical separation,
having a conflict); further increase
intimacy (e.g., share new experiences,
marital therapy)
SelfExpansion Model
(Aron & Aron, 1986)
Expansion of the
Passion declines over time as limits of
closeness are met and selfexpansion
through one's relationship slows.
Moderate to High; “Shared participation in
novel and arousing activities would
represent an easily managed route for
improving experienced relationship
quality.” (Aron et al., 2000, p. 282)
Participate in novel, exciting, “expanding”
activities with partner
Triangular Theory
of Love
(Sternberg, 1986)
drives and
other forms
of arousal
Passion declines over time as individuals
become habituated to one's partner
Low; Individuals have “little control over
the amount of motivational and other
arousal of the passion component one
experiences as a result of being with or
even looking at another person.”
(Sternberg, 1986, p. 120)
Analyze needs the relationship is fulfilling
and ensure these needs continue to be
met; analyze needs relationship is not
currently fulfilling and try to meet these
needs as well
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affection are thought to result in the increased rumination characteristic of limerence, as well as increased
perceived desirability of the potential partner. Indeed, many physiological correlates of limerence (e.g., heart
palpitations, trembling) are much the same as feelings of fear, nervousness, and anxiety (Tennov, 1979). Passion
typically grows in intensity until an individual becomes certain of their partner's reciprocated feelings (or lack
thereof) or transfers to another partner, at which point passion for that individual plateaus and eventually
declines. Although Limerence Theory grants that some individuals experience limerence for one person that lasts
a lifetime, such cases are thought to be extremely rare. The average duration of limerent or passionate feelings in
Tennov's (1979) estimation is approximately 2 years, based on her qualitative research, with the most typical
interval ranging from 18 months to 3 years. Marriage is thought to be especially likely to reduce feelings of
passion, as marriage represents one of the ultimate symbols of reciprocity of feelings, dramatically reducing
Controllability and upregulation of passion
Limerence Theory offers little advice for attempting to revive the limerent state, suggesting instead that it is
possible for a relationship lacking limerence to persist through formal commitment or other forms of bonding that
make it difficult from which to disengage. Furthermore, Tennov is skeptical not only of upregulation, but also of
downregulation of limerence. When discussing what to do if one's romantic partner becomes limerent for someone
else, Tennov's advice is to “Weep. Sympathize. Feel terrible. But recognize that limerence is basically involuntary.
Love vows reflect intense feeling and total sincerity, but there is no way that they can be made to stick when
feelings change” (p. 262).
Empirical support for uncertainty about reciprocity as a source of romantic passion has been largely mixed. In
support of Limerence Theory, studies have found that earlystage romantic relationships, which are usually higher
in passion, are also typically characterized by higher levels of partnerspecific attachment anxiety (Eastwick &
Finkel, 2008); that is, concern that their romantic partner does not want to be as close as they would like or does
not care about them as much as they care about their partner. Anxiously attached individuals in established
relationships also report greater sexual passion (a common component and correlate of romantic passion) for their
partner, are more likely to maintain desire over time, and report greater desire for sex when they feel insecure
about their partner's feelings (Davis et al., 2004). Thus, these findings suggesting that attachment anxiety is
associated with greater desire provide some suggestive, but indirect, evidence that uncertainty over a partner's
returned feelings may fuel passion.
Other studies have found evidence that individuals are most attracted to potential romantic partners in whom
they are uncertain of their returned romantic interest. In one series of experimental studies, for instance, women
reported the greatest attraction to profiles of men when they were uncertain of whether the man liked them “an
average” or “above average” amount, compared to when they were certain that man liked them an “above average”
amount (Whitchurch et al., 2011). However, in a subsequent investigation, this effect did not fully replicate, as
attraction did not significantly differ between the certain liking and uncertain conditions; furthermore, when a
withinsubject design was employed, participants became more attracted to the profiles when they gained certainty
that the individual liked them (Montoya et al., 2015). These conflicting results may be due to the relatively small
sample sizes of both of these studies (47 and 78 participants, respectively). In other, more highly powered studies,
uncertainty over being liked romantically has been negatively associated with romantic interest, especially in
established relationships. For example, in an experiment in which participants interacted with a confederate over
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an online messenger system, participants led to believe that their interaction partner had romantic interest in them
rated the confederate as more sexually desirable and expressed greater interest in future interactions compared to
those in an uncertain condition in which the confederate's romantic interest was left ambiguous (Birnbaum
et al., 2018).
Another potential reason for inconsistent findings across studies is that many of these studies use different
measures of passion or attraction toward a potential romantic partner. Unfortunately, although the Passionate
Love Scale (Hatfield & Sprecher, 1986) is wellestablished for use in ongoing relationships, there is no established
equivalent in the context of initial interactions with strangers. Thus, a variety of assessments of romantic interest,
attraction and sexual desire have been used across studies (e.g., sample items included “How much do you like him?”
in Whitchurch et al., 2011 compared with “To what extent do you think that the other participant is sexually
desirable?” in Birnbaum et al., 2018).
Other investigations have looked at behavior that might instill a sense of uncertainty over another's reci-
procity of feelings, such as a lack of responsiveness and playing “hardtoget” (Birnbaum et al., 2016; Birnbaum &
Reis, 2012; Dai et al., 2014; Reysen, & KatzarskaMiller, 2013). These studies too have found mixed evidence for
uncertainty or certainty inducing behaviors increasing romantic passion. For example, in a series of studies that
examined the influence of the responsiveness of oppositesex strangers—that is, how understood, validated, and
cared for the stranger made them feel, a potential signal of the stranger's romantic interest or desire for in-
timacy (Reis et al., 2004)—responsiveness decreased feelings of sexual desire among women, but increased
sexual desire among men (Birnbaum & Reis, 2012). This was suggested to be due to women being more
selective, potentially perceiving responsive men as desperate and less dominant, making them less sexually
appealing (Eastwick et al., 2007). In another series of studies, which only included male participants, participants
liked an “easytoget” partner over a “hardtoget” partner who seemed less interested in them romantically (Dai
et al., 2014). Thus, uncertainty may potentially play a larger role in the development of feelings of passion for
women. Overall, however, responsiveness and being “easytoget” were positively associated with sexual desire,
suggesting that uncertainty over reciprocated feelings is only sometimes associated with increased passion in
initial encounters.
Other studies have suggested yet further potential moderators for the role of uncertainty in fueling desire and
passion. For example, in one study, responsiveness increased sexual desire among individuals low in attachment
avoidance or high in attachment anxiety, but decreased sexual desire among individuals high in attachment
avoidance or low in attachment anxiety (Birnbaum & Reis, 2012). However, responsiveness was generally found to
increase sexual desire in established relationships overall, especially among women (Birnbaum et al., 2016). Other
findings suggest that whether ambiguity and doubts over a potential romantic partner's romantic interest increase
desire may depend on the physical attractiveness of that potential partner (Greitemeyer, 2010). Reciprocity may
increase desire to a greater degree for individuals already deemed physically attractive, whereas some degree of
ambiguity may increase desire for those who are moderately physically attractive or unattractive, perhaps by
making these individuals seem more selective and conferring mate value.
Thus, it is largely unclear from the existing empirical evidence whether or to what extent uncertainty drives
romantic passion. Given the number of conflicting findings, moderators, and variety of assessments used to examine
the role of uncertainty over reciprocated feelings on romantic passion, this area is ripe for a more systematic,
metaanalytic review.
Rate of change in intimacy model
According to the Rate of Change in Intimacy Model (Baumeister & Bratslavsky, 1999), passion is the first derivative
of intimacy over time.
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Source and trajectory of passion
According to this model, passion results from increases in intimacy that occur, for example, as romantic partners
learn new details about one another, share new experiences, and communicate affection toward one another. Thus,
this model suggests that when intimacy is rising quickly, passion will be high; in contrast, when intimacy is stable
and no longer increasing (few new details and experiences are being shared), passion will be low. Given that there is
often only so much information to be learned about a partner, intimacy often plateaus in relationships, at which
point passion starts to decline. Thus, this model views intense passion as occurring primarily early on in re-
lationships when increases in intimacy are the greatest followed by declines as intimacy plateaus.
Controllability and upregulation of passion
The Rate of Change in Intimacy Model holds a more optimistic view of the ability to increase passion in that it does
offer some practical suggestions for improving passion. For example, given that this model suggests passion is
driven by rapid increases in intimacy, it suggests that passion can be maintained longer by rationing intimacy so that
partners can still learn more about one another and enhance intimacy later on in the relationship. Because
Baumeister and Bratslavsky (1999) theorize that only so much passion can be felt at one time, they advise not to
“use up” all opportunities for increased intimacy too quickly in early interactions. Other suggestions include
engaging in reductions of intimacy, such as undergoing physical separation or engaging in conflict; however, they
note that such strategies may have negative consequences for the relationship that could outweigh potential
passion benefits. Finally, and perhaps most practically, they suggest engaging in activities with one's partner that
might help to further increase intimacy such as sharing new experiences or attending marital therapy which would
likely increase mutual selfdisclosure and understanding.
In support of this model, daily increases in intimacy as assessed by items capturing mutual selfdisclosure, feelings
of closeness, and communication of affection have been found to be associated with greater passion (Rubin &
Campbell, 2012). However, this same investigation did not find support for absolute levels of intimacy (i.e., having
achieved extremely high levels of intimacy) being associated with lower levels of passion. Thus, the prediction that
intimacy eventually plateaus once high levels of intimacy are achieved, making ever greater increases in intimacy
and, in turn, passion more difficult to achieve, was not supported. Similarly, overall higher levels of marital and
sexual intimacy are associated with greater, not lower, levels of sexual desire (Birnbaum et al., 2007; Patton &
Waring, 1985).
The previously discussed mixed evidence for responsiveness increasing sexual interest (Birnbaum & Reis, 2012;
Birnbaum et al., 2016) may also be taken as mixed, although indirect, evidence for rises in intimacy being a source of
romantic passion; that is, in addition to reducing uncertainty, responsiveness may also increase intimacy and
closeness. For example, in one experimental study, men experienced greater sexual desire for a confederate who
was responsive to the participant's personal disclosure (Birnbaum & Reis, 2012), suggesting that the intimacy
created by such an interaction fuels passionate feelings. However, women and those high in attachment avoidance
in the same study reported lower levels of sexual desire for the responsive confederate, suggesting mixed or
nuanced support for rises of intimacy being the ultimate source of passion.
Similarly, research showing that anxiously attached individuals report greater and more sustained sexual
passion for their partner (Davis et al., 2004), as well as report greater sexual interest in responsive partners
(Birnbaum & Reis, 2012), might also be seen as indirect evidence for the role of increases in intimacy in maintaining
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passion. Individuals who are anxiously attached desire greater closeness and intimacy, and therefore may expe-
rience greater passion in response to increases in intimacy. Anxiously attached individuals also tend to experience
greater fluctuations in intimacy due to their tendency for more volatile relationship conflict styles (Davis
et al., 2004). Thus, greater passion among anxiously attached individuals could also be explained by these in-
dividuals experiencing larger or more frequent rises in intimacy. Furthermore, given that those who are avoidantly
attached are less comfortable with and have a lower desire for intimacy, it would be hypothesized that they would
be less likely to experience passion, especially as they tend to respond to disagreements by distancing from a
partner (Davis et al., 2004). In support of this idea, individuals higher in attachment avoidance report lower levels of
sexual passion and display greater declines in passion over time (Davis et al., 2004).
Other evidence for the role of rises in intimacy as a source of passion comes from studies involving the “fast
friends” task in which individuals engage in mutual escalating disclosures (Aron et al., 1997; Slatcher, 2010; Welker
et al., 2014). In these studies, newly acquainted pairs of participants as well as established couples reported greater
attraction and passion when they engaged in the “fast friends” task as compared to a smalltalk control task.
Although this task is argued to increase selfexpansion, as discussed later, it could equally (and more directly) be
seen as experimental or causal support for rises in intimacy or closeness increasing passion, with numerous studies
finding the task to increase feelings of closeness (Aron et al., 1997; Sedikides et al., 1999).
Thus, although somewhat mixed support has been found for the Rate of Change in Intimacy Model, overall,
evidence suggests that rising levels of intimacy appear to be at least somewhat associated with feelings of romantic
SelfExpansion Model
Aron and Aron's (1986;1996) SelfExpansion Model suggests yet a different source of romantic passion. Rather
than passionate feelings arising from a state of uncertainty or increases in intimacy, Aron and Aron (1996) describe
passion as arising from individuals expanding their sense of self through their romantic partner or selfexpansion.
Source and trajectory of passion
According to this model, individuals possess a fundamental motivation to expand the self, and a central pathway to
do so is by forming relationships in which they include the other in the self, a process in which individuals selfexpand
by taking on their romantic partner's resources, perspectives, and characteristics. However, once a partner's
qualities and resources have been wellintegrated into the self, the rate of selfexpansion slows, yielding a decline in
romantic passion. Thus, the SelfExpansion Model of passion also predicts an initial spike in romantic desire
followed by waning passion. According to this model, partners are chosen because they are perceived as providing
the greatest or most likely opportunity for selfexpansion, although not always consciously (Aron & Aron, 1996).
Controllability and upregulation of passion
The SelfExpansion Model also presents an optimistic view of the ability to induce passionate states in more
established relationships. Although this model proposes that the ability to reach ever higher levels of selfexpansion
generally declines over time, Aron and colleagues (1986,2000,2004) suggest that further expansion, and thus
increases in passion, can be achieved by participating in novel, exciting activities with one's partner. Passion can be
achieved in longterm relationships by associating the partner or relationship with selfexpanding activities (Aron &
Aron, 1996): novel activities expand the self by providing new information and experiences.
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In support of this model, individuals passionately in love tend to display greater overlap in their selfconcept with a
romantic partner and this selfother overlap tends to increase over time (Agnew et al., 1998; Aron et al., 1991;
Aron & Fraley, 1999; Mashek et al., 2003; Quintard et al., 2018). However, in a rebuke of the argument that all
individuals possess a fundamental motivation to expand their sense of self, recent work suggests that not all
individuals equally desire to selfexpand and some may actively resist selfexpansion (Emery et al., 2015). The Self
Expansion Model does contend, however, that some individuals may have a reduced desire to selfexpand due to
experiences of failure or punishment associated with such efforts or due to too much selfother overlap being
perceived as threatening to one's personal control or sense of identity (Aron & Aron, 1996; Aron et al., 2004).
There is also limited evidence for the assertion that individuals might be particularly attracted to partners who
are likely to provide selfexpansion opportunities. People tend to prefer individuals they perceive as similar to
themselves (Byrne, 1961; Byrne et al., 1970; Montoya et al., 2008), suggesting that individuals do not attempt to
maximize the potential for selfexpansion by selecting individuals who have a greater number of novel traits and
perspectives for them to acquire. However, this could be due to individuals believing that dissimilar others may
not like them in return and therefore would ultimately not represent a potential partner who could provide
selfexpansion opportunities. In one study, for example, preferences for similar others disappeared when a
relationship with that other individual was made to seem more likely (Aron et al., 2006).
In contrast, the idea put forth in the SelfExpansion Model that novel, exciting activities are a possible means
for improving romantic passion has received empirical support (Aron et al., 2000; Coulter & Malouf, 2013; Muise
et al., 2019a; Reissman et al., 1993). For instance, couples randomly assigned to engage in novel and exciting ac-
tivities, compared with couples randomly assigned to engage in familiar and comfortable activities or a control
condition in which couples were not instructed to engage in any activities, reported greater sexual desire for their
partner (Muise et al., 2019a). Furthermore, engaging in novel, intimate discussions with strangers as a couple has
been found to increase romantic passion by creating shared selfexpansion experiences (Slatcher, 2010; Welker
et al., 2014). In one study, for instance, couples assigned to engage in escalating selfdisclosure with another couple
(the “fast friends” task discussed earlier) displayed greater subsequent passion for their romantic partner compared
to couples assigned to engage in a smalltalk control task with another couple (Welker et al., 2014). Similarly,
individuals with more creative personalities (i.e., personal traits and dispositions associated with individuals judged
to be more creative) and who engage in more creative behaviors—behaviors that likely result in selfexpansion—are
better able to maintain romantic passion over time compared to less creative individuals (Carswell et al., 2019).
Thus, overall, selfexpansion as a source of passion has also received a fair amount of empirical support,
although again, with some qualifications.
Triangular Theory of Love
Finally, in describing the three components of his Triangular Theory of Love, Sternberg (1986) describes passion (as
opposed to intimacy and commitment) as originating from motivational drives and other forms of arousal that lead
to romance, physical attraction, sexual consummation, and related phenomena.
Source and trajectory of passion
These sources of arousal are said to arise from any number of needs being fulfilled by a romantic partner; in many
cases these could be sexual needs, but it is equally possible that other needs, such as those of selfesteem, suc-
corance, nurturance, affiliation, dominance, submission, and selfactualization, can be sources of motivational
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arousal that lead to passion. Although this theory has received little theoretical and empirical attention, we
interpret this arousal as being psychological or physical arousal associated with the motivational pursuit of a goal or
need. When a romantic partner serves as an instrumental means for achieving one's goal or need, they become
associated with this arousal. The Triangular Theory of Love also predicts that the trajectory of passion generally
follows a pattern of steady decline after an initial rise. Declines in passion, according to this theory, occur largely
due to habituation to a partner meeting one's needs, reducing the associated arousal.
Controllability and upregulation of passion
The Triangular Theory of Love describes passion as having low conscious controllability. Individuals have “little
control over the amount of motivational and other arousal of the passion component one experiences as a result of
being with or even looking at another person” (p. 120). This theory further views passion as highly unstable and
suggests that the motivational arousal driving passion comes and goes rather unpredictably. Despite this skepticism
over the ability to control feelings of passion, the theory does suggest, given this conceptualization of passion
arising from needs being met by the partner, that a possible avenue for increasing passion might be to first analyze
the needs that the partner currently is and is not fulfilling. The individual would then attempt to make their partner
instrumental to some of these unfulfilled needs, for which they would not be habituated to their partner helping
them meet.
Compared to the other three models and theories of romantic passion, the Triangular Theory of Love has received
the least empirical attention. Given that limited research exists in support of this hypothesized source of romantic
passion, perhaps due to the majority of empirical research related to this theory focusing on the taxonomy of the
different components of love with the theorized source of passion being overlooked, we therefore review some-
what tangentially related research pertaining to relationships and goal pursuit. In support of this theory, research
has found that individuals tend to draw closer to those who are helpful to their goals (Fitzsimons & Shah, 2008).
However, this desire for closeness may dissipate once successful goal progress has been made (Fitzsimons &
Fishbach, 2010). Recent research also suggests that individuals feel closer to partners who are instrumental to
more of their goals (Orehek & Forest, 2016; Orehek et al., 2018), and that couples in which the male partner takes
up a greater share of the housework have greater sexual frequency (Gager & Yabiku, 2010). Future research is
needed, however, to fully evaluate whether needfulfillment represents the primary source of passionate feelings,
as well as whether there are particular needs that, when met by a romantic partner, are especially likely to fuel
Although all four models and theories share some commonalities, such as largely being inline with the empirically
supported assertion that passion should normatively decrease over time after an initial spike (Acker & Davis, 1992;
Carswell et al., 2019; Tucker & Aron, 1993), they offer divergent views of what ultimately causes passion. In
particular, the Rate of Change in Intimacy Model and Limerence Theory appear to offer conflicting views on what
drives passion, especially with regards to partner responsiveness. According to Limerence Theory, ambiguity over
reciprocated romantic interest drives passion, suggesting that a highly responsive partner—whose attentiveness
would likely suggest returned affection—would decrease feelings of passion. However, according to the Rate of
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Change in Intimacy Model, having a partner be responsive to one's disclosures would increase intimacy and
closeness, fueling passion. These theories also offer different suggestions about how one might best induce feelings
of initial attraction and passion in a potential partner. For instance, Limerence Theory suggests that concealing the
true extent of one's feelings for a partner (or “playing games”) is an effective strategy for fueling a romantic in-
terest's desire. By delaying perceived full reciprocation, this strategy is thought to allow the intensity of these
feelings to continue to increase. According to this theory, fully reciprocating feelings early on may prevent the
development of fully realized limerence and passion. In contrast, the Rate of Change in Intimacy Model would
suggest that concealing one's feelings, as well as reducing disclosures and responsiveness inherent to “playing
games” would hamper rises in intimacy, and result in a potential romantic partner having lower feelings of passion.
One reason why these two theories offer such conflicting predictions about how to best achieve romantic
passion is that they may actually predict two different types of passion. Recent research suggests that romantic
passion may be divided into two types (Acevedo & Aron, 2009; Graham, 2011): a more obsessive form and a form
more strictly related to feelings of romantic love. In this dual model of passion, the obsessive form encapsulates the
ruminative, cognitive preoccupation elements of romantic passion, whereas the romantic love form encapsulates
longing for union without the obsessive element (Acevedo & Aron, 2009). Limerence Theory, given its focus on
obsession and rumination, may more closely model the source of the obsessive form, whereas the Rate of Change in
Intimacy Model may more closely model the source of the romantic love form.
One intriguing element of this dual model is that the obsessive form of passion declines much more precipi-
tously in relationships than the romantic love form, which is far more robust, according to initial investigations
(Acevedo & Aron, 2009). This suggests that some sources of romantic passion may be more critical at different
relationship stages than others. For instance, uncertainty could be a stronger driver of passion earlier on in re-
lationships, whereas increasing intimacy could be a stronger driver of passion as relationships become more
More recently, Ratelle and colleagues (2013) have similarly proposed that romantic passion may follow a dual
model. Applying Vallerand and colleagues (2003) dual model of passion originally developed in the context of
passion toward activities (e.g., work, education, sport, and leisure activities), this dual model suggests two different
forms of romantic passion: the similarly named obsessive romantic passion and harmonious romantic passion
(Carbonneau & Vallerand, 2013; Carbonneau et al., 2016; Paquette et al., 2020; Rapaport et al., 2018; Ratelle
et al., 2013). In applying this theory of passion toward activities to romantic relationships, however, the meaning of
romantic passion takes on a somewhat different meaning than the classic conceptualization of romantic passion or
passionate love in relationship science. Although obsessive passion in this dual model somewhat closely follows
from classic conceptualizations of romantic passion (e.g., top loading items from the obsessive romantic passion
scale include “I’m emotionally dependent on my partner” and “I have difficulty controlling my need to see my
partner”), and in particular, to items associated with the obsessive component identified by Acevedo and
Aron (2009), the second form of passion—harmonious passion—does not closely align with the definition of
romantic passion. Instead, harmonious passion might be more accurately characterized as a measure of relational
selfexpansion. For example, the two highest loading items of this scale (i.e., “The new things that I discover within
our relationship allows me to appreciate my partner even more” and “My relationship with my partner allows me to
live varied experiences”; Ratelle et al., 2013) appear to be quite similar to items in established measures of self
expansion (i.e., “How much does your partner help to expand your sense of the kind of person you are?” and
“How much does being with your partner result in you having new experiences?”; Lewandowski & Aron, 2002).
Given that selfexpansion is theorized to be a source of passion rather than a measure of passion itself and that
harmonious passion, according to this new model, does not include a longing or desire for union with a romantic
partner in its definition, this assessment and theory may be less relevant to assessing romantic passion and its
source as classically conceptualized in relationship science. However, this model does highlight the need for better
integration across the field of romantic passion, as well as better integration of research on passion for activities
and romantic passion as they may be mutually informative.
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In contrast to the differences apparent between the Rate of Change in Intimacy Model and Limerence Theory,
on first blush, the Rate of Change in Intimacy Model and SelfExpansion Model appear to hold largely similar
predictions regarding the source of romantic passion. However, rises in intimacy and selfexpansion as sources of
passion offer subtly, but critically different, predictions for when passion would arise. More specifically, the Self
Expansion Model predicts that passion increases when one takes on the resources, perspectives, and identities
of a romantic partner. Although this may easily take place through intimate discussions, acquiring a partner's
resources and qualities would be best achieved through partner disclosures. In contrast, in the same intimate
discussion, passion through rises in intimacy according to the Rate of Change in Intimacy Model would be best
achieved by one's own disclosures that are then validated by a romantic partner. Thus, these two models might
offer divergent predictions for when passion would arise based on whether one is sharing with versus receiving
intimate disclosures from a romantic partner.
Another critical difference between these models is that the SelfExpansion Model presumes that positive
growth of an individual's sense of self precedes feelings of passion, whereas the Rate of Change in Intimacy Model
does not require any changes to an individual's selfconcept for passion to arise. It is unclear whether perceived
selfgrowth is necessary to experience passion. Is having a novel, exciting experience that does not grow one's
sense of self equally likely to increase feelings of passion? For example, in the “bridge study,” men found an
attractive female confederate more attractive when they met her on a scary suspension bridge than on a safe,
stable footbridge (Dutton & Aron, 1974). This increased attraction was likely due to a misattribution of arousal and
not due to selfchange. One might suggest that effects of selfexpansion are due to misattribution of arousal (either
physical or psychological) rather than selfchange (Foster et al., 1998; White et al., 1981). The Rate of Change in
Intimacy Model, on the other hand, makes no presumptions of changes in selfconcept. Instead, any experience that
would increase connection and closeness to a romantic partner is theorized to increase passion. Furthermore,
experiencing physical or psychological arousal would also not be required to feel passion; engaging in familiar and
comfortable activities that enhance closeness and connection should be equally likely to enhance passion as
engaging in novel and exciting ones, somewhat in conflict with empirical evidence (Muise et al., 2019a).
In contrast to both of these models, the Triangular Theory of Love suggests that achieving selfexpansion and
intimacy through a romantic partner may just be two of many goals that partners might meet that may drive
passion. Although selfexpansion and intimacy are perhaps especially central needs, and ones that are likely met by
romantic partners, the Triangular Theory of Love offers a broader view of what drives romantic passion—that is,
motivational arousal from a partner meeting any psychological need or goal. Thus, the SelfExpansion Model and
Rate of Change in Intimacy may offer just a couple of many pathways through which passion might be increased.
That said, it is unclear whether a partner meeting any need or goal can increase passion or whether having only
certain needs met by a partner sparks passionate feelings. Passion might only increase if a partner meets needs that
increase their overall perceived mate value. For example, if a partner meeting certain needs also highlights a
partner in a negative light (e.g., arguing with a waiter on your behalf, but simultaneously highlighting their own
disagreeableness), it may not increase feelings of passion. On the other hand, taking on a partner's resources
(material, knowledge, and social assets that can facilitate one's goals; Aron et al., 2004) as described in the Self
Expansion Model might subsume what is discussed in the Triangular Theory of Love’s hypothesis that newly met
needs drive passion, suggesting the SelfExpansion Model might equally be considered a more inclusive and general
theory or model.
One potential criticism of all of these models is the potential for bidirectionality of observed associations. For
example, it is unclear whether rises in intimacy are the cause or consequence of romantic passion. Given that
passion is defined as a desire for intimacy, it seems unclear whether rises in intimacy as described by the Rate of
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Change in Intimacy Model (Baumeister & Bratslavsky, 1999) are the cause of passion or the result of passion. If
an individual feels passion for a partner—that is, desires intimacy with a partner—it is perhaps unsurprising that
they would then seek out and achieve greater intimacy with that partner. The SelfExpansion Model suffers from
similar issues of directionality. Although individuals display increased selfconcepts that include a greater number
of content domains when answering the question “who are you today?” after falling in love compared to before
(Aron et al., 1995), it is unclear whether this is the cause or consequence of passion. When passionately in love,
partners may spend hours or all night talking and learning about one another, not because this fuels their love,
but because this is what they crave when they are in love. This appetite for reciprocal selfdisclosure then leads
to greater selfother overlap as one learns and takes on the traits of their partner. Similarly, individuals might
adopt their partner's traits to increase closeness or engage in selfgrowth to make themselves more appealing to
their partner.
Given that these four theories and models largely predated recent findings suggesting people can and do report
feeling intense passion for more than one person at a time (Balzarini et al., 2019; Muise et al., 2019b), they do not
consider consensually nonmonogamous relationships. For example, with the exception of Limerence Theory, these
perspectives do not offer predictions for how passion for one partner may affect passion for another. Limerence
Theory, as previously mentioned, suggests that limerence can only be felt for one person at a time (Tennov, 1979).
Future research might examine whether obsessive passion might be felt for multiple individuals simultaneously, or
whether such intense rumination is only possible for one individual at a time given how cognitively demanding such
obsession may be. However, it might be just as likely that thoughts about one romantic partner could spur related
thoughts about another if they are cognitively linked, and thus fueling rather than extinguishing even this
potentially more fragile form of passion.
Future work is also needed to better integrate and contrast the competing predictions of these theories. For
example, future research might experimentally manipulate whether one is the source or the recipient of disclosure,
or both, in an effort to disentangle whether intimacy or selfexpansion is a primary source of passion. If rising
intimacy is the primary source of passion, either of these conditions might be likely to produce feelings of closeness
and intimacy, although perhaps disclosing and having those disclosures accepted warmly might be especially likely
to induce passion. In contrast, only disclosing to partner should do little to enhance passion according to self
expansion theory; instead, a partner disclosing new traits or perspectives would mainly achieve selfexpansion,
and in turn, passion.
Furthermore, although previous studies have experimentally increased passion or sexual desire for a romantic
partner through reciprocal disclosure (e.g., Welker et al., 2014) or shared selfexpanding experiences (e.g., Muise
et al., 2019a), these studies often omit critical tests of the mechanism through which these manipulations increase
passion. Future studies ought to measure and test whether increased intimacy, uncertainty, motivational arousal, or
selfgrowth mediates such effects or manipulate them more directly. For example, recent research suggests in-
dividuals spontaneously take on even fictionalized traits that have been randomly assigned to a partner (Slotter &
Gardner, 2009). Experimentally manipulating whether a partner discloses a novel or existing trait, and then
measuring subsequent trait adoption and passion, might be one way to test whether selfconcept growth specif-
ically drives passion.
The ultimate source of passion may likely be a mix of all these sources. However, without considering how
these models and theories conflict, interact and might be integrated, we may overlook new or more precise ways to
cultivate passion. In particular, the Triangular Theory of Love's more motivational take on the source of romantic
passion remains underdeveloped, but in light of emerging work on relationships and goal pursuit (Fitzsimons &
Fishbach, 2010; Fitzsimons & Shah, 2008; Orehek & Forest, 2016; Orehek et al., 2018), this could be a particularly
fruitful area for novel ways of achieving passion. In reviewing existing theories and models of romantic passion, we
hope this review will inspire new, more refined models of romantic passion that integrate across these theories and
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Although four major models and theories have been proposed for understanding what fuels romantic passion, these
perspectives have largely developed separately with few attempts to identify ways in which they might conflict or
be integrated. In this integrative review, we have identified critical ways in which they suggest divergent
predictions and future research that may improve our understanding of what ultimately drives passion.
This work has been supported in part by a postdoctoral fellowship from the Office of VPResearch at University of
Toronto Mississauga awarded to Kathleen L. Carswell and a Social Sciences and Humanities Research Council of
Canada (SSHRC) Insight Grant awarded to Emily A. Impett. The opinions and conclusions expressed herein are
those of the authors and do not necessarily reflect the opinions of the SSHRC.
Kathleen L. Carswell
Emily A. Impett
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How to cite this article: Carswell, K. L., & Impett, E. A. (2021). What fuels passion? An integrative review of
competing theories of romantic passion. Social and Personality Psychology Compass, e12629.
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... Uncertainty is the driving force behind the development and maintenance of limerence (2). The individual experiencing limerence feels an attraction towards a particular "limerent object" (LO) whose willingness to reciprocate is uncertain. ...
... Since then, Wolf has proposed a tool to measure limerence and conducted initial work towards validation (12). Carswell and Impett point to the lack of a consistent measure of attraction as a key limitation in the existing research on limerence (2). As this is a single case study, generalization of the results to other patients with limerence cannot be assumed before interventions are demonstrated effective in multiple trials. ...
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Limerence is an underresearched condition of unknown prevalence that causes significant loss of productivity and emotional distress to sufferers. Individuals with limerence display an obsessive attachment to a particular person or “limerent object” (LO) that interferes with daily functioning and the formation and maintenance of healthy relationships. The current study proposes a conceptualization of the condition in a 28-year-old individual and describes a treatment approach using cognitive-behavioral techniques, most notably exposure responsive prevention as used in the treatment of obsessive-compulsive disorder. The number and type of compulsive rituals performed by the treated individual were notably decreased at 9-month follow-up after treatment, and a subjective assessment of dysfunctional thought patterns related to the LO also suggested improvement. A novel screening instrument is presented, as validated screening instruments do not yet exist. Implications for diagnosis and treatment are discussed.
Although engaging in exciting, shared activities with a partner is one strategy for warding off relational boredom , people might be less likely to pursue these activities when they are bored, which could have implications for the maintenance of passion in romantic relationships. In the current study, we assessed couple members' (N = 122 couples) daily experiences of relational boredom, the occurrence and quality of exciting , shared activities, and passion in a 21-day daily diary study and followed up with participants 3 months later. Overall, there was evidence that relational boredom obstructed the occurrence and quality of exciting, shared activities. In turn, less enjoyable shared activities were associated with lower daily passion, and engaging in fewer exciting, shared activities accounted for declines in passion over time. Implications of the findings for passion decay are discussed. K E Y W O R D S relational boredom, relationship maintenance, self-expansion, shared leisure Statement of Relevance: The benefits of exciting, shared activities for promoting passion in intimate relationships are well-documented, however, less is known about what challenges couples face when engaging in such activities in their daily lives. In the current study, we demonstrate that relational boredom impeded exciting, shared activities in couples' daily lives, which was associated with a lower passion that day, as well as declines in passion over time.
The article presents a conceptual model of close relationships. Close relationships are a specific and multicomponent phenomenon in the living space of modernity. On the basis of the analysis of sources and rethinking of the data obtained earlier, close relationships are considered as a type of interpersonal relations. It is a meaningful, selective relationship of people aimed at satisfying their need for love and belonging, based on affiliative feelings and attachment. Closeness in relationships is defined as a structural property of the dyad, including the strength, frequency, psychological distance, the variety of interrelationships that exist between people. It is noted that close relationships are set by social roles. Reciprocal roles, for example, parent and child, husband and wife set the initial belonging of these relationships to the category of close, but do not guarantee the presence in them of intimacy as a qualitative characteristic. The invariant (partners' attachment to each other, emotional experiences, psychological distance; value-semantic unity; involvement) categorical attributes of close relationships were identified. The variation signs characterising their main types (romantic, marital, friendship, love, kinship) are described. It is noted that the dynamics conditioned by the totality of factors determines the variety of close relationships – dysfunctional and functional. We understood the limitations and prospects for further developments in this area.
Sex is a crucial factor that impacts the quality and stability of relationships, yet many couples report recurrent sexual issues – such as discrepancies in their desired sexual frequency or levels of sexual desire – that detract from their relationship quality. This article describes how applying the theory of communal motivation from relationship science to the sexual domain of relationships can shed light onto understanding how couples can maintain desire over time, remain satisfied in the face of conflicting sexual interests, and decline one another’s sexual advances in ways that protect their relationship. We integrate a decade of research on communal motivation, sexual rejection, and responses to sexual rejection to provide a better, and more holistic, understanding of how partners can successfully balance their sexual needs to ultimately reap the powerful rewards of a fulfiling sexual connection.
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Three studies explored the role of attachment styles as determinants of romantic passion and investigated how the interplay between these variables contributes to conflict resolution strategies within a romantic relationship. In Study 1, a secure attachment style was positively, and an avoidant attachment style negatively, associated with harmonious passion. Moreover, secure and anxious attachment styles were positively related to obsessive passion. In Study 2, we replicated and extended these findings by demonstrating that harmonious and obsessive passions positively predicted the use of adaptive and maladaptive conflict resolution strategies, respectively. In Study 3, results of Study 2 were replicated over time providing us with some information concerning the direction of the relationships among attachment, romantic passion, and conflict resolution strategies. Overall, the present results suggest that attachment styles are a determinant of romantic passion and that romantic passion mediates the relationships between attachment styles and the use of adaptive and maladaptive conflict resolution strategies.
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Romantic partners provide both erotic and nurturing experiences, though these may emerge more strongly in different phases of a relationship. Unlike individuals in monogamous relationships, those in polyamorous relationships can pursue multiple romantic relationships simultaneously, potentially allowing them to experience higher levels of eroticism and nurturance. This research examined eroticism and nurturance among individuals in polyamorous and monogamous relationships. As expected, polyamorous participants experienced less eroticism but more nurturance in their relationships with their primary partner compared to secondary. Furthermore, people in polyamorous relationships reported more nurturance with primary partners and eroticism with secondary partners compared to people in monogamous relationships. These findings suggest that polyamory may provide a unique opportunity for individuals to experience both eroticism and nurturance simultaneously.
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The Dualistic Model of Passion (Vallerand et al. Journal of Personality and Social Psychology, 85, 756–767, 2003) suggests the existence of two types of passion: harmonious (HP) and obsessive (OP). Previous research in positive psychology has shown that passion can be oriented toward activities, as well as romantic partners, and that both are important for people’s well-being and relationships. The purpose of the present research was to integrate these two areas of passion by examining how one’s type of passion for a joint activity and for a romantic partner influences the experience of positive and negative emotions during the joint activity, and its impact on the strengthening of the relationship. Results from a path analysis (N = 205) revealed that HP for the joint activity and for the romantic partner both positively predicted the experience of positive emotions during the joint activity that, in turn, positively predicted the strengthening of the relationship. Conversely, OP for the joint activity and for the romantic partner both positively predicted the experience of negative emotions during the joint activity that, in turn, negatively predicted the strengthening of the relationship. These findings suggest that these two domains of passion make an important and unique contribution to romantic relationships.
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The present research examines the implications of having relationship partners who serve as means to multiple goals. Specifically, we test the hypotheses that (a) partners who serve more goals will be evaluated as more interpersonally close, supportive, and responsive than those who serve fewer goals, and (b) partners who serve more goals will be less common in social networks than those who serve fewer goals. Three studies (N = 1,064) found consistent support for these hypotheses while examining relationships with all members of participants’ active social network and their full range of goal pursuits. In addition, we found that the association between number of goals a partner serves and relationship evaluation is stronger for people who perceived their social networks as less (vs. more) instrumental on average, and among people who perceived their relationships as less close, less supportive, and less responsive, on average. Implications for close relationships are discussed.
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Do feelings of uncertainty about existing or potential relationships spice up relationships or impair them? Six studies employed complementary methods to examine whether relationship uncertainty affects partners' sexual desirability, and whether expressions of partners' regard influence these effects. In Studies 1-4, participants interacted online with confederates who were either clear or vague about their romantic intentions. Results showed that relationship uncertainty had detrimental effects on confederates' appeal only when they were perceived as uninterested in the participants. Moreover, explicit expressions of romantic interest fostered certainty about confederates' behavioral intentions, thereby enhancing their appeal. Using survey and daily experiences methodologies, Studies 5 and 6 replicated these findings in established relationships, demonstrating that partners' regard predicted lower uncertainty, which, in turn, was associated with greater perceived partner desirability. These findings suggest that inhibiting desire serves as a mechanism aimed at protecting the self from investing in a relationship whose future is uncertain.
Romantic passion typically declines over time, but a downward trajectory is not inevitable. Across 3 studies (1 of which encompassed 2 substudies), we investigated whether creativity helps bolster romantic passion in established relationships. Studies 1A and 1B revealed that people with highly creative personalities report not only greater overall passion but also an attenuation in the tendency for passion to decline as relationship duration increases. Studies 2 and 3 explored positive illusions about the partner's physical attractiveness as a possible mediator of the effect of creativity on passion. Cross-lagged panel analyses in Study 2 indicated that being creative is linked to a tendency to view the partner as especially attractive, even relative to the partner's own self-assessment. Path analyses in Study 3 provided longitudinal evidence consistent with the hypothesis that positive illusions about the partner's attractiveness (participant's assessments, controlling for objective coding of the partner's attractiveness) mediate the link between creativity and changes in passion over time. Study 3 also provided longitudinal evidence of the buffering effect of creativity on passion trajectories over time, an effect that emerged not only for self-reported passion but also for objectively coded passion during a laboratory-based physical intimacy task 9 months later. A meta-analytic summary across studies revealed a significant overall main effect of creativity on passion, as well as a significant moderation effect of creativity on risks of passion decline (e.g., relationship length).
In the early stages of romantic relationships, sexual desire is often intense, but over time, as partners get to know each other, desire tends to decline. Low sexual desire has negative implications for relationship satisfaction and maintenance. Self-expansion theory suggests that engaging in novel activities with a long-term romantic partner can reignite feelings of passion from the early stages of a relationship. Across 3 studies using dyadic, daily experience, longitudinal, and experimental methods, we find evidence for our central prediction that engaging in self-expanding activities with a partner is associated with higher sexual desire. In turn, we found that higher desire fueled by self-expansion is associated with greater relationship satisfaction. Self-expansion, through sexual desire, is also associated with an increased likelihood that couples will engage in sex, and when they do engage in sex, they feel more satisfied with their sexual experiences. We also demonstrate that the benefits of self-expansion for relationship satisfaction are sustained over time, and that the effects cannot be attributed solely to increases in positive affect, time spent interacting with the partner or closeness during the activity. Implications for self-expansion theory and sexual desire maintenance in relationships are discussed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
The present research introduces the construct of a decay theory of passion—a lay belief that romantic passion decline is irreversible—and investigates how this construct interacts with existing levels of passion for one’s romantic partner to predict lower relationship commitment and greater pursuit of romantic alternatives. Across three studies employing experimental and nonexperimental procedures—and a set of meta-analytic syntheses including additional studies—results generally supported the hypotheses that, although low passion is linked to lower commitment and greater pursuit of romantic alternatives, such effects are stronger when adherence to decay beliefs is high rather than low. These effects tended to be independent of effects of destiny and growth theories (Knee, 1998), a related set of lay theories in the domain of relationships. Mediated moderation analyses revealed that the moderating effect of decay theories on relationship commitment mediates the moderating effect of decay theories on the link between low passion and the pursuit of romantic alternatives. Discussion addresses the possibility that changing one’s beliefs surrounding the nature of romantic passion may be an important, but previously overlooked, means for preventing one from prematurely abandoning an otherwise satisfying relationship.
Although it is typically presumed that heterosexual individuals only fall in love with other-gender partners and gay-lesbian individuals only fall in love with same-gender partners, this is not always so. The author develops a biobehavioral model of love and desire to explain why. The model specifies that (a) the evolved processes underlying sexual desire and affectional bonding are functionally independent; (b) the processes underlying affectional bonding are not intrinsically oriented toward other-gender or same-gender partners; (c) the biobehavioral links between love and desire are bidirectional, particularly among women. These claims are supported by social-psychological, historical, and cross-cultural research on human love and sexuality as well as by evidence regarding the evolved biobehavioral mechanisms underlying mammalian mating and social bonding.
Consensually nonmonogamous (CNM) relationships allow individuals to fulfill their sexual needs with multiple partners, but research has yet to investigate how having one’s sexual needs met in one relationship is associated with satisfaction in another relationship. We draw on models of need fulfillment in CNM relationships and theories of sexual communal motivation to test how sexual need fulfillment in one relationship is associated with satisfaction in another, concurrent relationship. Across two studies, individuals in CNM relationships (N = 1,054) who were more sexually fulfilled in their primary relationship reported greater relationship satisfaction with their secondary partner. In Study 2, men who were more sexually fulfilled in their secondary relationship reported greater relationship satisfaction with their primary partner, but women who were more sexually fulfilled with their secondary partner reported lower sexual satisfaction in their primary relationship. Implications for communal relationships and need fulfillment are discussed.