The Molecule of More

THE MOLECULE OF MORE

drugs such as heroin and OxyContin scramble both the desire circuit
and the liking circuit (where dopamine acts and where endorphin acts),
they are among the most addictive drugs there are. Marijuana is similar.
It also interacts with both circuits, stimulating dopamine as well as the
endocannabinoid system. This dual effect leads to unusual results. 
Boosting dopamine can lead to enthusiastic engagement with things
that would otherwise be perceived as unimportant. For example, mari-
juana users have been known to stand in front of a sink, watching water
drip from the faucet, captivated by the otherwise mundane sight of the
drops falling over  and  over  again. The  dopamine-boosting effect is  also 
evident when marijuana smokers get  lost  in  their own  thoughts, floating 
aimlessly through imaginary worlds of their own creation. On the other
hand, in some situations marijuana suppresses dopamine, mimicking
what H&N molecules tend to do. In that case, activities that would typi-
cally be associated with wanting and motivation, such as going to work,
studying, or taking a shower, seem less important.

IMPULSIVENESS AND THE DOWNWARD SPIRAL

Many of the decisions that addicts make, particularly the harmful deci-
sions, are impulsive. Impulsive behavior occurs when too much value
is placed on immediate pleasure and not enough on long-term conse-
quences. Desire dopamine overpowers the more rational parts of the
brain. We make choices that we know are not in our best interest, but
we feel powerless to resist. It’s as if our free will has been compromised
by an overwhelming urge for immediate pleasure; perhaps it’s a bag of
potato chips when we’re on a diet, or splurging on an expensive night
out that we can’t really afford.
Drugs that boost dopamine can also boost impulsive behavior. A
cocaine addict once said, “When I do a line of cocaine, I feel like a new
man. And  the  first  thing that  new  man  wants is  another line  of cocaine.” 
When the addict stimulates his dopamine system, his dopamine system
responds by demanding more stimulation. That’s why most cocaine
addicts smoke cigarettes when they use cocaine. Like cocaine, nicotine