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Romantic Love: An fMRI Study of a
Neural Mechanism for Mate Choice
HELEN FISHER,
1
*ARTHUR ARON,
2
AND LUCY L. BROWN
3
1
Department of Anthropology, Rutgers University, New Brunswick, New Jersey 08901
2
Department of Psychology, State University of New York at Stony Brook,
Stony Brook, New York 11794
3
Departments of Neurology and Neuroscience, Albert Einstein College of Medicine,
Bronx, New York 10461
ABSTRACT
Scientists have described myriad traits in mammalian and avian species that evolved to
attract mates. But the brain mechanisms by which conspecifics become attracted to these
traits is largely unknown. Yet mammals and birds express mate preferences and make mate
choices, and data suggest that this “attraction system” is associated with the dopaminergic
reward system. It has been proposed that intense romantic love, a cross-cultural universal, is
a developed form of this attraction system. To determine the neural mechanisms associated
with romantic love we used functional magnetic resonance imaging (fMRI) and studied 17
people who were intensely “in love” (Aron et al. [2005] J Neurophysiol 94:327–337). Activation
specific to the beloved occurred in the right ventral tegmental area and right caudate nucleus,
dopamine-rich areas associated with mammalian reward and motivation. These and other
results suggest that dopaminergic reward pathways contribute to the “general arousal”
component of romantic love; romantic love is primarily a motivation system, rather than an
emotion; this drive is distinct from the sex drive; romantic love changes across time; and
romantic love shares biobehavioral similarities with mammalian attraction. We propose that
this attraction mechanism evolved to enable individuals to focus their mating energy on
specific others, thereby conserving energy and facilitating mate choice—a primary aspect of
reproduction. Last, the corticostriate system, with its potential for combining diverse cortical
information with reward signals, is an excellent anatomical substrate for the complex factors
contributing to romantic love and mate choice. J. Comp. Neurol. 493:58 – 62, 2005.
©2005 Wiley-Liss, Inc.
Indexing terms: romantic love; dopamine; fMRI; mate choice
Charles Darwin distinguished between two types of sex-
ual selection: intrasexual selection, by which members of
one sex evolve traits that enable them to compete directly
with one another to win mating opportunities, and inter-
sexual selection, by which individuals of one sex evolve
traits that are preferred by members of the opposite sex, a
process known as “mate choice” (Darwin, 1871). Scientists
have described many physical and behavioral traits in
birds and mammals that evolved by mate choice. The
peacock’s tail feathers is the standard example. But no one
had defined the corresponding neural mechanism by
which the “display chooser” comes to prefer certain traits
and focuses his/her mating energy on a particular conspe-
cific, thereby making a mate choice. Yet it is well estab-
lished that many creatures have mate preferences, focus
their courtship energy on these specific individuals, and
make mate choices. In fact, the phenomenon of mate
choice is so common in nature that the ethological litera-
ture regularly uses several terms to describe it, including
“mate choice,” “female choice,” “mate preference,” “indi-
vidual preference,” “favoritism,” “sexual choice,” and “se-
lective proceptivity” (Andersson, 1994).
Fisher (Fisher, 1998; Fisher et al., 2002a) hypothesized
that mate choice is associated with a specific brain system
for “courtship attraction” that operates in tandem with
other neural systems, including the circuits for the sex
*Correspondence to: Helen Fisher, Department of Anthropology, Rutgers
University, New Brunswick, NJ 08901.
E-mail: helenfisher@helenfisher.com
Received 30 March 2005; Revised 24 June 2005; Accepted 5 August 2005
DOI 10.1002/cne.20772
Published online in Wiley InterScience (www.interscience.wiley.com).
THE JOURNAL OF COMPARATIVE NEUROLOGY 493:58 – 62 (2005)
©2005 WILEY-LISS, INC.
drive, sensory perception, discrimination, and memory;
courtship attraction is expressed at different times and to
different degrees in different species according to each
species’ specific reproductive strategy; and this neural
network evolved to enable “display choosers” to focus their
mating energy on specific, potential mating partners,
thereby conserving courtship time and metabolic energy.
In most mammalian and avian species this attraction is
brief, lasting only minutes, hours, days, or weeks. In hu-
mans the neural mechanism associated with courtship
attraction is developed, forming the physiological basis of
what is commonly known as passionate love, obsessive
love, “being in love,” or romantic love.
We chose to study courtship attraction in humans by
looking at early stage intense romantic love for several
reasons. Early stage, intense romantic love is regarded as
a human universal or near universal experience (Jankow-
iak and Fischer, 1992 ); this neural system is associated
with a specific constellation of identifiable motivations,
emotions, and behaviors (Tennov, 1979; Hatfield and
Sprecher, 1986; Shaver et al., 1987; Hatfield et al., 1988;
Harris and Christenfeld, 1996; Fisher, 1998; Gonzaga et
al., 2001) and these identifiable features are easily ob-
served, quantified, and tabulated in humans. Some of
these traits studied by the above-cited investigators in-
clude focused attention on the beloved, increased energy,
elation, and mood swings. Often, the lover experiences a
pounding heart, sweaty palms, and other sympathetic
nervous system reactions while with the beloved and “sep-
aration anxiety” when apart. Lovers express emotional
dependence; they change their habits to impress and/or
remain in contact with the beloved. Adversity heightens
romantic passion, known as “frustration attraction.” Lov-
ers exhibit extreme empathy toward the beloved; many
are willing to die for this “special” individual. They also
express sexual desire for him or her, as well as intense
sexual possessiveness, yet the craving for emotional union
supersedes the need for sexual contact. A central charac-
teristic of human romantic love is intrusive, obsessive
thinking about the beloved. Rejected lovers generally pro-
test and try to win the beloved back, as well as express
“abandonment rage” and despair. Romantic passion is also
involuntary, difficult to control, and regularly imperma-
nent.
We used functional magnetic resonance imaging (fMRI)
methods to test two hypotheses about the neural mecha-
nisms associated with romantic love (Aron et al., 2005).
First, romantic love would involve subcortical dopaminer-
gic pathways that mediate reward (Liebowitz, 1983;
Fisher, 1998). Second, romantic love would involve neural
pathways associated with goal-directed behaviors, sup-
porting the prediction that romantic love is a goal-directed
state that leads to a range of emotions, rather than a
specific emotion (Aron and Aron, 1991; Aron et al., 1995).
For details of the investigation, see Aron et al. (2005).
Briefly, 10 women and seven men were recruited by word
of mouth and with flyers seeking individuals who were
currently intensely in love. The age range was 18 –26
years (M !20.6; median !21), and the reported duration
of “being in love” was 1–17 months (M !7.4; median !7).
Each participant was orally interviewed in a semistruc-
tured format to establish the duration, intensity, and
range of his or her feelings of romantic love. Each also
completed the Passionate Love Scale (PLS), a 9-point Lik-
ert scale self-report questionnaire which measures several
traits commonly associated with romantic love (Hatfield
and Sprecher, 1986) (Cronbach’s alpha for questionnaire
reliability in this study !0.81; Cronbach, 1951).
A preliminary investigation identified a photograph of
the beloved as an effective stimulus for eliciting feelings of
intense romantic love (Mashek et al., 2000). So our proto-
col employed photographs and consisted of four tasks pre-
sented in an alternating block design: For 30 seconds each
participant viewed a photo of his/her beloved (positive
stimulus); for the following 40 seconds each participant
performed a countback distraction task; for the following
30 seconds each participant viewed a photograph of an
emotionally neutral acquaintance (neutral stimulus); for
the following 20 seconds each participant performed a
similar countback task. The countback task involved view-
ing a large number, such as 8,421, and mentally counting
backwards (beginning with this number) in increments of
seven. We included the countback task to decrease the
carryover effect after the participant viewed the positive
stimulus because it is difficult to quell intense feelings of
romantic love. This four-part sequence (or a counterbal-
anced version beginning with the neutral stimulus) was
repeated six times; the total stimulus protocol was 720
seconds (12 minutes). Prescanning instructions were to
think about a nonsexual, euphoric experience with the
beloved; postscanning interviews established that the par-
ticipants had engaged in romantic thinking and feeling.
Group activation specific to the beloved occurred in sev-
eral regions, including the right ventral tegmental area
(VTA), localized in the region of A10 dopamine cells (Aron
et al., 2005) (Fig. 1). The VTA is a central part of the
brain’s “reward system” (Wise, 1996; Schultz, 2000;
Martin-Soelch et al., 2001) associated with pleasure, gen-
Fig. 1. Group activation re-
gions detected as individuals
looked at an image of their beloved
compared to an image of an ac-
quaintance (see Aron et al., 2005,
for details). The regions of activa-
tion (white) are from anatomically
normalized data and are superim-
posed on a template brain from
SPM99. A: The right ventral teg-
mental area (arrow) was activated.
B: The right caudate nucleus (ar-
row) was activated. Data from
other studies of mammals suggest
that these regions are involved in
reward and motivation functions.
59fMRI STUDY OF MATE CHOICE
eral arousal, focused attention, and motivation to pursue
and acquire rewards (Schultz, 2000; Delgado et al., 2000;
Elliot et al., 2003).
The VTA sends projections to several brain regions
(Gerfen et al., 1987; Oades and Halliday, 1987; Williams
and Goldman-Rakic, 1998), including the caudate nucleus,
where we also found group activations, specifically in the
right medial and posterodorsal body (Aron et al., 2005).
The caudate plays a role in reward detection and expec-
tation, the representation of goals, and the integration of
sensory inputs to prepare for action (e.g., Schultz, 2000;
Martin-Soelch et al., 2001; Lauwereyns et al., 2002;
O’Doherty et al., 2002). Zald et al. (2004) found that pre-
dictable monetary reward presentation caused dopamine
release in the medial caudate body where we found acti-
vation.
These data suggest that our hypotheses are correct:
romantic love is associated with subcortical dopaminergic
pathways in the reward system, and romantic love is
primarily a motivation system, which leads to various
emotions, rather than a specific emotion. However, acti-
vation of subcortical dopaminergic pathways of the VTA
and caudate nucleus may comprise only the “general
arousal” component (Pfaff, 1999) of early-stage intense
romantic love.
Nevertheless, these data suggest two important things
about romantic passion: Foremost, romantic love may be a
primary motivation system, a fundamental human mating
drive. Pfaff (1999) defines a drive as a neural state that
energizes and directs behavior to acquire a particular
biological need to survive or reproduce; and he reports that
all drives are associated with the activity of dopamine.
Like drives, romantic love is tenacious; it is focused on a
specific reward; it is not associated with any particular
facial expression; it is exceedingly difficult to control; and
it is associated with dopamine-rich neural regions (Fisher,
2004). Drives lie along a continuum. Thirst is almost im-
possible to control, while the sex drive can be redirected,
even quelled. Falling in love is evidently stronger than the
sex drive because when one’s sexual overtures are re-
jected, people do not kill themselves or someone else.
Rejected lovers sometimes commit suicide or homicide.
These data also indicate that romantic love is distinct
from the sex drive, as suggested earlier (Aron and Aron,
1991; Fisher, 1998), because fMRI studies of human sex-
ual arousal show regional activation in largely different
brain regions than those we saw for our participants (Red-
oute et al., 2000; Arnow et al., 2002).
Using fMRI, Bartels and Zeki (2000:3829) also investi-
gated brain activity in 17 men and women who reported
being “truly, deeply, and madly in love.” But the partici-
pants in that study had been in love substantially longer
than those in our study (28.8 months vs. 7.4 months t[32]
!4.28, P"0.001). They were also less intensely in love.
This was established because both study groups were (ser-
endipitously) administered the same questionnaire on ro-
mantic love, the PLS (scores of 7.55 vs. 8.54, t[31] !3.91,
P"0.001).
Bartels and Zeki (2000; 2004) found activity in regions
of the ventral tegmental area and caudate nucleus, as we
did. However, they also found activity in the anterior
cingulate and mid-insular cortex, results which stimu-
lated us to examine our subset of subjects in longer rela-
tionships (8 –17 months), as compared to our shorter-term
participants. Among these participants, several more
brain regions showed activity, including the right mid-
insular cortex, the right anterior and posterior cingulate
cortex, and the right posterior cingulate/retrosplenial cor-
tex. Thus, we confirmed Bartels and Zeki’s (2000) finding
that these brain regions are involved in longer-term love
relationships. In addition, these combined data suggest
that the neural mechanism for mate choice is dynamic: it
changes across time.
Our subjects in longer-term relationships also showed
increased activity in the ventral pallidum. The ventral
pallidum has been associated with attachment behaviors
in prairie voles (Lim et al., 2004; Lim and Young, 2004).
These data suggest that as romantic love changes across
time, brain systems associated with attachment increase
activity—perhaps to enhance relationship stability and
motivate parenting behaviors.
It has been proposed (Fisher, 1998; Fisher et al., 2002b)
that mammalian and avian species evolved three distinct,
dynamic, interrelated brain systems for courtship, mat-
ing, and parenting: The sex drive evolved to motivate
individuals to seek a range of mating partners; courtship
attraction (and its developed form, human romantic love)
evolved to motivate individuals to focus their mating en-
ergy on specific partners, thereby conserving mating time
and energy; and attachment evolved to motivate mates to
remain together long enough to complete species-specific
parental duties. These data may suggest one of the neural
mechanisms by which this transition from attraction to
attachment occurs.
As discussed above, it is well established that birds and
mammals have mate preferences and make mate choices.
This attraction is regularly associated with heightened
energy, focused attention, obsessive following, sleepless-
ness, loss of appetite, possessive “mate guarding,” affilia-
tive gestures, goal-oriented courtship behaviors, and in-
tense motivation to win a specific mating partner (Fisher,
2004), traits also associated with human early-stage, in-
tense romantic love. Moreover, animal studies indicate
that elevated activity of central dopaminergic neurons
may play a primary role in mammalian mate preference
(Fabre-Nys, 1998; Wang et al., 1999; Gingrich et al., 2000).
When a female prairie vole is mated with a male, she
forms a distinct preference for this partner, and when a
dopamine agonist is infused into the nucleus accumbens
she begins to prefer a male present at the time of infusion,
even if she has not mated with this male (Gingrich et al.,
2000; Liu and Wang, 2003). Also, electrochemical studies
in male rats have shown increased dopamine release in
the dorsal and ventral striatum in response to the pres-
ence of a receptive female rat (Robinson et al., 2002; Mon-
tague et al., 2004).
Thus, evidence from human fMRI studies support the
hypothesis that multiple reward regions using dopamine
are activated during feelings of romantic love, and this
human phenomenon shows behavioral and neural system
similarities with other mammalian species. The human
form of courtship attraction, romantic love, may have be-
gun to develop by 3.5 million years BP, because recent
analysis of sexual dimorphisms in Australopithecus afa-
rensis suggests that early hominids were “principally mo-
nogamous” by this time (Reno et al., 2003).
Our fMRI results also suggest something about integra-
tive events in the brain that lead to complex behavior and
emotion. For example, we conducted a between-subjects
analysis correlating degree of the BOLD response with
60 H. FISHER ET AL.
subjects’ scores on the PLS. While viewing their beloved,
those who self-reported higher levels of romantic love also
showed greater activation in the right anteromedial cau-
date body (r !0.60; P!0.012). This result provides
strong evidence for the link between a specific brain region
and a specific brain function, romantic love. However, this
specific region was also activated during anticipation of a
monetary reward (Knutson et al., 2001), during reward-
based stochastic learning (Haruno et al., 2004), and dur-
ing attention tasks (Zink et al., 2003). Thus, this area of
the anteromedial body of the caudate may be specifically
associated with the rewarding, visual, and attentional
aspects of romantic love. Because the caudate nucleus has
widespread afferents from all of the cortex except V1
(Kemp and Powell, 1970; Selemon and Goldman-Rakic,
1985; Saint-Cyr et al., 1990; Eblen and Graybiel, 1995;
Flaherty and Graybiel, 1995) and is organized to integrate
diverse sensory, motor, and limbic functions (Brown,
1992; Parent and Hazrati, 1995; Brown et al., 1998;
Haber, 2003), caudate nucleus anatomy is an appropriate
mechanism for integrating the various aspects of this mul-
tifactor physiological and behavioral state, romantic love.
The range and variation of motivations and emotions
associated with human romantic love are undoubtedly
produced by many neural systems, acting in parallel and
dynamic combinations. Nevertheless, several results sup-
port our hypotheses that early-stage, intense romantic
love is importantly influenced by subcortical reward re-
gions that are dopamine-rich (Fisher, 1998); that romantic
love is primarily a neural system associated with motiva-
tion to acquire a reward, rather than a specific emotion
(Aron and Aron, 1991); that this brain system is distinct,
yet overlapping with the sex drive; that this brain system
is derived from mammalian precursors (Fisher, 2004); and
that it evolved as a mechanism to enable individuals to
respond to sexually selected courtship traits and motivate
individuals to make a mate choice (Fisher et al., 2002a).
In a study of 37 societies, Buss (1994) reports that men
and women rank love, or mutual attraction, as the first
criterion for choosing a spouse. This brain system has
inspired love songs, love poems, love magic, myths and
legends about love, and suicide and homicide cross-
culturally (Jankowiak and Fischer, 1992; Fisher, 2004).
Romantic love is most likely a primary aspect of our com-
plex human reproductive strategy.
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62 H. FISHER ET AL.