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27
Chapter 2
DRUGS
You want it . . . but will you like it?
In which dopamine overwhelms reason to create consuming
desire for the most destructive behaviors imaginable.
A guy walks past a restaurant, smells burgers cooking. He imagines taking
a bite; he can almost taste it. He’s on a diet, but at this point he can’t
think of anything he wants more than that hamburger, so he goes in and
orders one. Sure enough, the first bite is wonderful, but the second bite, not
so much. With each bite, his enjoyment is less and less—so much for the
hoped-for “hamburger heaven.” He finishes anyway, not really knowing
why, then feels a little nauseated and very much defeated because he didn’t
stick to his diet.
As he heads back into the street, the thought crosses his mind: there’s a
big difference between wanting something and liking it.
28
THE MOLECULE OF MORE
WHO’S IN CONTROL OF YOUR BRAIN?
At some point, everyone asks the question, why? Why do I do the things
that I do? Why do I make the choices that I make?
On the surface, this seems like an easy question: we do things for
a reason. We put on a sweater because we’re cold. We get up in the
morning and go to work because we need to pay the bills. We brush our
teeth to prevent tooth decay. Most of what we do is for the sake of other
things; things such as feeling warm, having money to pay bills, and to
avoid being scolded by the dentist.
The problem is that you can ask this question as long as you like.
Why do we want to stay warm? Why do we care if we pay the bills?
Why do we want to avoid the dentist’s scolding? Children play this
game all the time: “It’s time to go to bed.” Why? “Because you need to
get up for school in the morning.” Why? “Because you need an educa-
tion.” Why? And so on.
The philosopher Aristotle played this same game, but with a more
serious purpose. He looked at all the things we do for the sake of some-
thing else and wondered if there was an end to it all. Why do you
go to work, really? Why do you need to make money? Why do you
have to pay bills? Why do you want the electricity to stay on? Where
does it end? Is there anything we seek for itself only, not because it
leads to something else? Aristotle decided there was. He decided there
was a single thing that lay at the end of every string of Whys, and its
name was Happiness. Everything we do, ultimately, is for the sake of
happiness.
It’s hard to argue with this conclusion. After all, it makes us happy
to be able to pay our bills and have electricity. It makes us happy to have
healthy teeth and educated minds. It may even make us happy to suffer
pain, if we’re doing it for a worthy cause. Happiness is the polestar that
guides our journey through life. When faced with a range of options,
we choose the one that leads to the most happiness.
Except we don’t.
Our brains aren’t wired that way. Think of how many people you
know who just “fell into” their careers, or who chose their college based
29
DRUGS
on nothing but a gut feeling that it was the right one. Only once in a
while do we sit down to consider our options rationally, weighing one
against the other. Such an exercise is tiring work, and the outcome is
rarely satisfying. We seldom reach the point at which we can say with
certainty that we made the right decision. It’s much easier just to do
what we want, so that’s what we do.
The next question, of course, becomes, “Well, then, what do we
want?” The answer depends on whom you ask: one person might
want to be rich, another might want to be a good father. The answer
depends on when you ask, too. The 7:00
pm
answer might be “dinner”;
the 7:00
am
answer might be “another 10 minutes of sleep.” Sometimes
people don’t know what they want at all; other times they want lots of
things at once—things that they cannot have at the same time, because
they conflict with one another. Most people, when they see a donut,
want to eat it. Most people, when they see a donut, want to not eat it.
What’s going on?
HOW TO STAY ALIVE
Andrew was a young man in his twenties who worked for a company that
sold enterprise software. He had a confident, outgoing personality, and was
one of the top salespeople in the company. He was so consumed with his
work that he spent almost no time relaxing or pursuing other activities,
except one: picking up women. He estimated that he had slept with over a
hundred women but had never experienced an intimate relationship with any
of them. It was something he longed for, something he knew was important
for his long-term happiness, and he recognized that continuing his pattern
of one-night stands wasn’t going to get him there. Nevertheless, the pattern
continued.
Wanting, or desire, flows from an evolutionarily old part of the brain
deep inside the skull called the ventral tegmental area. It is rich in dopa-
mine; in fact, it is one of the two main dopamine-producing regions.
Like most brain cells, the cells that grow there have long tails that wind
30
THE MOLECULE OF MORE
through the brain until they reach a place called the nucleus accumbens.
When these long-tailed cells are activated, they release dopamine into
the nucleus accumbens, driving the feeling we know as motivation. The
scientific term for this circuit is the mesolimbic pathway, although it’s
easier to simply call it the dopamine desire circuit (Figure 1).
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