The science of romantic love
(Top Posts - Science - 021206)

The following article scientifically assesses
one of the most powerful and impactive
emotions present in humans, that being
the emotion of romantic love ...

Key abbreviations/terms used often in
the following:

RL: romantic love, a cognitive-affective
state characterized by intrusive and
obsessive fantasizing concerning
reciprocity of amorant feelings by
the object of the amorance.
PEA: phenylethylamine, a kind of natural
amphetamine that revs up the brain
and the central nervous system.
caudate nucleus: the site of the reptilian
brain, thought to be 65m years old in
evolutionary terms, the central 'con-
troller' of RL.
dopamine: chemical released in response
to RL, causing highly targeted attention,
stamina, energy, all focused on reward.
seritonin: nerve chemical which controls
impulses, unruly passions, obsessive
behavior, a chemical which aids the
sense of power over action (the feeling
of "being in control"), a chemical which
is diluted and cancelled out by PEA
and dopamine in response to RL.

oxytocin: a hormone released when
actual contact with the love object
occurs -- stroking, love play, kissing,
leading eventually to coitus -- re-
lease of said hormone explodes
like a firework display in the brain,
releasing showers of natural opi-
ates known as endorphins, a kind
of natural crack: a mega-reward!

At orgasm a man's oxytocin levels
can increase by a factor of five. In
women the oxytocin levels can be
even higher during intercourse.

Oxytocin, moreover, combines with
the hormone vasopressin, which is
associated with vivid emotional mem-
ories, visual, tactile, aural and nasal,
consolidating the image and asso-
ciated deep feelings for the love
object.

- - -
Feb. 12, 2006

Love is the drug
http://www.timesonline.co.uk/tol/life_and_style/article725491.ece
- - -

Excerpts [with my own comments,
responding to the article, included
in brackets]
:

Falling head over heels for someone can
feel heavenly or hellish. But can scientists
explain what's really happening?

John Cornwell reports

There's a joke e-mail doing the rounds of
the neuroscience labs:

"Why did the chicken cross the road?"
To which: "Because its dopaminergic
neurons fired synchronously across the
synapses of its caudate nucleus, trig-
gering motor contractions propelling the
organism forward, while emitting 'cluck'
distress signals, to a goal predeterm-
ined by its hippocampal road mappings."

- - -
[Hence, a good example of the innate dif-
ficulty most humans have when faced with
the actual nature of behavior, in this case
the behavior of a road-crossing chicken,
preferring simplistic (and false, and in this
case often joke-centered) explanations
when confronted with the actual nature of
reality.]

- - -

Love of family, and platonic love, are not
so susceptible to scientific probing. But
since my first disastrous infatuation with
a girl I believed to be my eternal soul mate,
I've been convinced that romantic love,
RL, is a profoundly physical rather than
spiritual phenomenon.

- - -
[Recall Dawkins' stance that human behav-
ior is a result of physics, that all that hap-
pens is a result of physics, that blame of
and punishment of and guilt-trips toward
a human for his/her behavior is as absurd
as is blame of and punishment of and
guilt-trips toward a car for its behavior.]

- - -

In RL, our neurons and our hormones, our
brains and our blood pressure, our stom-
achs and hearts, are in a state of upheaval.
And if we check out the behaviour of our
close primate relatives, we can detect links
between human bonding of the RL type,
and evolutionary survival pressures.

...

The feeling that RL is akin to being "besot-
ted" lies deep in western folk memory. ...
But is it generated within, or outside, the
body?

... the favoured chemical explanation [for
romantic love]
focuses on a molecule
called PEA: phenylethylamine, a kind of
natural amphetamine that revs up the brain
and the central nervous system.

PEA causes the experience of euphoria,
hyperventilation, increased heart rate,
dilated pupils, and secretions of odours
that can seduce an unsuspecting love
object. The eye of the chemical storm is
in the brain.

The brain in RL resembles a huge geo-
logical and meteorological event: earth-
quakes, cyclones, tsunamis. It's as if the
ecosystem of the lover's brain, the pulsing
grey-blue-green planet in the skull, suffers
a drastic depletion of the protective cor-
tical ozone layer, triggering neuronal glo-
bal warming with consequent atmospheric
storms.

The notion that reason goes to pot in RL
fits with a popular mind-brain theory first
proposed in the 1970s.

The outer brain, or cortex, which evolved
late in evolution, is associated with rational
thought and intelligence.

The midbrain, known as the limbic system,
regulates the emotions.

But there's a deep inner core, located at
the final bulb where the spinal cord enters
the brain, ... "the reptilian brain", where lurk
our darker, primeval, instinctive behaviours
of territoriality, mating and reward-seeking.

When two separate researchers ... used
functional magnetic resonance imaging to
explore the neural basis of RL, the brains
of their lovelorn volunteers lit up precisely
in that deep region known as the caudate
nucleus: the site of the reptilian brain,
thought to be 65m years old in evolution-
ary terms.

The more passionate the subjects, the
more active the caudate nucleus.

The reptilian brain connects directly with
the limbic system, where ... "the chemical
storms, leading to infatuation, almost cer-
tainly have their physical origin".

In RL the music of cortical sweet reason
is drowned out by the primitive drumbeats
of our limbic and reptilian brains, stimu-
lating cascades of PEA in the central ner-
vous system.

At the same time, adrenaline levels are
boosted, prompting the release of a
chemical called dopamine. Dopamine is
associated with highly targeted attention,
stamina, energy, all focused on reward.

As these powerful chemicals run riot
down the neuronal pathways, they dilute
and cancel out the nerve chemical called
serotonin. Serotonin controls impulses,
unruly passions, obsessive behaviour: it
aids the sense of power over action, the
feeling of "being in control".

A severe depletion of serotonin can in-
duce panic, anxiety, queasiness, manic
behaviour, depression, obsession: "I
can't get her/him out of my mind, I'm
thinking about her/him all the time."

Patients with compulsive disorders, such
as nonstop hand-washing and bulimia,
are often prescribed Prozac (fluoxetine
hydrochloride), which increases the acti-
vation of lowered serotonin in the syn-
apses.

In the language of pharmacology, Prozac
is an SSRI, a selective serotonin-reuptake
inhibitor. SSRIs prevent serotonin being
swallowed up too quickly in the synapses.
There are serious suggestions that the
lovesick should be given a good dose of
an SSRI.

- - -
[Sidenote, Prozac and other SSRIs, in
most patients, have the serious side ef-
fect of adversely impacting the sexual
performance of the patient taking the
SSRI, 'tis the primary reason why alter-
native anti-depressants, not having ad-
verse sexual side effects, have been
developed in the past 10 years.]

- - -

So what, chemically speaking, is hap-
pening to the lovesick -- the jilted, the
jealous?

The lover needs the constant fix of en-
counters with the love object to satisfy
and dampen the excitation of those
cataracts of PEA; any thwarting ("I can't
get no-o... satis-faction!") can only lead
to further drenching of PEA, resulting in
even more drastic loss of serotonin.

This explains the highs and lows of the
lovesick, the out-of-control symptoms
of possessiveness, goose pimples,
butterflies in the stomach, restlessness,
inability to concentrate, sleeplessness:
that generalised delicious agony called
infatuation.

But should RL be reciprocated, there
follows the second stage: sexual ful-
filment, in which the hormone testos-
terone becomes rampant in men, and
also in women, especially at ovulation
and even beyond the menopause.

When actual contact with the love object
occurs -- stroking, love play, kissing,
leading eventually to coitus -- a heady
hormone identified as oxytocin explodes
like a firework display in the brain, releas-
ing showers of natural opiates known as
endorphins, a kind of natural crack: a
mega-reward!

At orgasm a man's oxytocin levels can
increase by a factor of five. In women
the oxytocin levels can be even higher
during intercourse. Oxytocin, moreover,
combines with the hormone vasopressin,
which is associated with vivid emotional
memories, visual, tactile, aural and nasal,
consolidating the image and associated
deep feelings for the love object.

That piece of music, that particular scent,
the purr of their voice, the shape of that
nose exciting so much passion. The
oxytocin highs, with their consequent
endorphin hits, do much to explain the
withdrawal symptoms when the love
object goes cold and, worst of all, is
seen in the arms of another. Small won-
der psychiatrists have likened disap-
pointed love to acute depression.

But what of lust, pure and simple?

Lust can flourish independently of RL.

Obviously, it can exist simultaneously
with RL.

In some lovers, though -- the capricious,
the promiscuous, the congenitally un-
committed -- satisfaction of lust can kill
accompanying RL stone dead.

...

- - -
Love is the drug (page 2 of 3)
http://www.timesonline.co.uk/tol/life_and_style/
article725491.ece?token=null&offset=12

- - -

Excerpts:

But all the chemical and neuronal rioting
of RL raises another chicken question:
does falling in love cause the chemical
upheaval, or vice versa? Chicken or egg?

There's an explanation originally pro-
pounded by [an] ... ethologist (specialist
in comparative animal behaviour studies)
[who] observed in ducks a phenomenon
known as imprinting. There is a critical
moment for a nestling bird, when its brain
and central nervous system are geared
to be bonded to its mother.

In the absence of the mother, the bird
will bond with whatever animal it first
encounters. The imprinting mechanism
is crucial for survival, since it is supposed
to attach to its protective parent like an
invisible wire of inseparability.

...

Noting the similarity between a deprived
child and a disappointed lover, for ex-
ample, psychologists have identified
this reconfigured imprinting in adult
love: RL. ... the lover will stare into the
love object's eyes and make coochicoo
noises. If jilted, the lover ... weeps, falls
into depression, and can self-harm.

If the sexual bonding is successful, long-
term attachment is in prospect.

It occurs, if it does, after the RL high has
run its course ... This new stage is fortui-
tous [for continuation of the RL relation-
ship]
, since typically after 18 months to
three years the PEA, dopamine and oxy-
tocin cascades dwindle to a trickle (a
result, neuroscientists say, of a kind of
neutrotransmitter burnout).

Which brings us to the question: what
do men and women really want from a
love partner?

Human statistics with a dash of animal
behavioural psychology come to the
explanatory rescue.

More than a decade ago [a] psychol-
ogist ... canvassed over 10,000 people
in 37 cultures of the world, to conclude
that women are programmed to seek
out men who are breadwinners, whereas
men are wired to detect breeding poten-
tial signalled by big hips [?-but not fat-
laden, at least not in western cultures
in modern times]
, youth, healthy skin,
bright eyes and lustrous hair.

And yet, despite the powerful determin-
ing forces of evolution, RL can reemerge
in a variety of combinations.

While still warmly attached, in the bosom
of the family, it's common to be attracted
to another available love object. ...

"It seems to be the destiny of human-
kind that we are neurologically able to
love more than one person at a time.
You can feel profound attachment for
a long-term spouse, while you feel ro-
mantic passion for someone in the
office or your social circle, while you
feel the sex drive as you read a book,
watch a movie, or do something else
unrelated to either partner."

Human mates who stay together are
rewarded in evolutionary terms by the
knowledge that their genes are being
perpetuated. But adultery lurks con-
stantly in the wings.

Men make a huge investment in their
offspring, and it would be unthinkable
to see a rival's genes prosper. In this
sense, jealousy is an evolutionary
strategy to prevent cuckoldry.

"Sexual jealousy ... is activated when
one is confronted either with signs that
someone else has an interest in one's
mate or with signs of defection by
one's mate, such as flirting with some-
one else."

- - -
[Aside -- while sexual jealousy may be
a common human trait, it's something
that many(?)/some(?) humans do not
experience on anywhere near the level
indicated above -- end aside]

- - -

Despite strong motives and ideals for
single attachment, human promiscuity
is pervasive, especially among males
(British heterosexual males admit to
an average of six sexual partners in
a lifetime, as opposed to an average
of four admitted by women).

...

In recent years it has been discovered
that the most neglected aspect of
sexual attraction in women is their
desire for steadfast kindness in a mate.

...

RL involves acts of narcissism and self-
love as you project your ego onto the
significant other, leading, at the height
of the love experience, to a sense of
oceanic unity.

At the same time, RL creates depen-
dency, which can lead to vulnerability.

...

- - -
Love is the drug (page 3 of 3)
http://www.timesonline.co.uk/tol/life_and_style/
article725491.ece?token=null&offset=24

- - -

Excerpts:

... there are significant lessons to be
learnt from the science of statistics.

Divorces, steadily on the increase these
past five decades, now run at a rate of
more than 50% in the highly concentrated
residential districts of the southeast of
England.

The figures do not include the failed
heterosexual partnerships that never
reached marriage, [married relation-
ships that continue despite the adverse
nature of the relationships on many, if
not all, levels]
, nor homosexual partner-
ships, but the statistics reinforce the
message that we should be sceptical
about RL as a prelude to lasting love.

...

- - - end excerpts - - -