The Molecule of More

Shawn had gained a little weight, but Samantha found him more attrac-
tive than ever. Shawn thought Samantha looked better than ever, too. Even 
though he appreciated how great she looked dressed up, he confided to his 
friends that nothing was sexier to him than when she woke up with tangled 
hair and no makeup, wearing one of his old T-shirts from college. Lately 
they kept their voices low to steal a few extra minutes while the baby slept, 
because the morning, alone and unguarded, was a rare moment when they 
could enjoy the presence of each other. 
Samantha had learned how to help Shawn overcome the insecurities 
that held him back at work, and he found ways to free up time for her, so 
she could pursue her master’s degree. But more and more they just savored 
each other’s company. Sometimes they didn’t talk at all, and while once that 
would have seemed strange to them, these days it just felt right. Samantha 
remembered the night Shawn reached for her, stroked her hip, then took back 
his hand. She heard him flip over and make the sound he always made just 
before going to sleep.
“What’s wrong?” she asked.
“Nothing,” said Shawn. “Just making sure you’re there.”
Dopamine got the nickname “the pleasure molecule” based on exper-
iments with addictive drugs. The drugs lit up dopamine circuits and 
test participants experienced euphoria. It seemed simple until studies 
done with natural rewards—food, for example—found that only unex-
pected rewards triggered dopamine release. Dopamine responded not 
to reward, but to reward prediction error: the actual reward minus the 
expected reward. That’s why falling in love doesn’t last forever. When 
we fall in love, we look to a future made perfect by the presence of our 
beloved. It’s a future built on a fevered imagination that falls to pieces 
when reality reasserts itself twelve to eighteen months later. Then what? 
In many cases it’s over. The relationship comes to an end, and the search 
for a dopaminergic thrill begins all over again. Alternatively, the pas-
sionate love can be transformed into something more enduring. It can 
become companionate love, which may not thrill the way dopamine 

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THE MOLECULE OF MORE
does, but has the power to deliver happiness—long-term happiness 
based on H&N neurotransmitters such as oxytocin, vasopressin, and 
endorphin.
It’s like our favorite old haunts—restaurants, shops, even cities. Our 
affection for them comes from taking pleasure in the familiar ambience: 
the real, physical nature of the place. We enjoy the familiar not for 
what it could become, but for what it is. That is the only stable basis for 
a long-term, satisfying relationship. Dopamine, the neurotransmitter 
whose purpose is to maximize future rewards, starts us down the road 
to love. It revs our desires, illuminates our imagination, and draws us 
into a relationship on an incandescent promise. But when it comes to 
love, dopamine is a place to begin, not to finish. It can never be satis-
fied. Dopamine can only say, “More.”

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LOVE
FURTHER READING
Fowler, J. S., Volkow, N. D., Wolf, A. P., Dewey, S. L., Schlyer, D. J., MacGregor, 
R. R., . . . Christman, D. (1989). Mapping cocaine binding sites in human and 
baboon brain in vivo. Synapse, 4(4), 371–377.
Colombo, M. (2014). Deep and beautiful. The reward prediction error hypothesis 
of dopamine. Studies in History and Philosophy of Science Part C: Studies in History