 |
Now available The paperback from DAW Books |
Praise for Ed's previous novel, Lost in Translation: "Edward Willett has arrived, and SF is the richer for it." - Robert J. Sawyer, Hugo Award-winning author of Hominids "A believable, absorbing, thought-provoking and highly enjoyable read." - Kathy Tyers, Author of the Firebird trilogy, Star Wars: The Truce at Bakura, and Star Wars: Balance Point "An interstellar adventure story worthy of Golden Age masters like Isaac Asimov and Robert A. Heinlein. " - Dave Duncan, author of the Seventh Sword series, the King's Blades series and Children of Chaos |
LIBRARY ***
***
***
***
***
***
***
***
***
***
***
*** |
AddictionCopyright 2001 by Edward Willett
We sometimes throw
around the word "addiction" a little loosely.
"I'm addicted to Harlequin Romances" someone might say, or, "I'm
addicted to CBC Radio." True addiction, however, isn't just doing something frequently because you enjoy it, or even a habit that's hard to break: it's a complex condition that involves the brain's biochemistry, genetic factors, social factors, and more. Not everyone who smokes a cigarette, or drinks a glass of whiskey, or even shoots up heroin will become addicted to nicotine, or alcohol, or opiates. But every addict began as a casual user, someone who discovered a substance that made him or her feel good. Drugs produce a feeling
of pleasure because by provoking temporary changes in the brain.
Specifically, they affect the "reward pathway"--linked areas of
the brain central to feelings of pleasure. A central player in the
reward pathway is a brain chemical called dopamine, released whenever we
feel pleasure. Normally, dopamine is quickly reabsorbed.
Many addictive drugs, however, seem to block this process,
causing dopamine levels--and the person whose brain they're in--to
remain high. Chronic use of these
substances over time can alter the brains of some people, leading to
addiction. One effect is
tolerance: ever-larger doses are needed to achieve the same pleasurable
effect. Eventually, the
brain becomes so altered that the feeling of pleasure can't be generated
at all; instead, the brain is so used to having the drug it can't
function without it, and so the addict actually requires the drug just
to function. That, in turn, leads to
a fierce craving when the addict tries to quit. That's one reason only
20 percent of addicts achieve a stable abstinence after a single
detoxification attempt. Craving can linger for months or years. Craving is also a
conditioned response to people, places and activities associated with
drug use, which is why recovering addicts are urged to avoid such
things. Negative mood
states--depression, economic stress, the loss of a loved one--often
contribute to relapses, too.
And when an addict relapses, he or she is likely to return to former or
even heavier levels of drug use (alcoholics, for example, are likely to
drink as if making up for lost time). Stress seems to play a
role in why some people become addicts in the first place; the more
stress someone is under when he or she begins using drugs, the more
likely he or she is to become addicted.
But genetics seems to play a role, too. For instance, studies
have found that people with a specific variant of a gene that regulates
the brain's levels of dopamine are much less likely smoke than people
without that gene, and if they do smoke, probably started later, were
less likely to start before age 16, and find it easier to quit. People with that gene
also displayed weaker novelty-seeking characteristics than those without
it, and studies have shown that people who are drawn to novelty--are
always looking for the next new thing--find it harder to quit smoking
than those who aren't. We also know genes
influence the attraction to caffeine--a third to two-thirds of a woman's
vulnerability to caffeine is apparently due to heredity, according a
recent study. (And yes,
caffeine can be addictive:
if you need four or five cups a day to feel good, if you get a headache
when you haven't consumed caffeine for a while, if you need increasing
amounts to get the same effect--then you're using caffeine as a drug.
The biological processes aren't really much different from what
goes on in the brains of people addicted to alcohol or nicotine or
heroin.) And what about that
other substance some people claim to be addicted to, chocolate?
Well, it certainly contains chemicals that affect the reward
pathway of the brain. But
studies suggest the craving for is more cultural than physiological.
One recent study showed that while chocolate is the number-one
craving among American women, far more so than among American men, in
Spain, both sexes rated their desire for chocolate about the same, and
the overall craving was lower than in the U.S. In other words, we may
crave chocolate more because of the marketing might of the chocolate
companies than because we're addicted to it physically. Which reminds me--I sure could go for a Cadbury's chocolate Easter egg right about now! These weekly columns on science appear in the Regina (Saskatchewan) Leader Post and Red Deer (Alberta) Advocate.. They are available for one-time publication or regular syndication to any interested newspapers, magazines or on-line publications. E-mail me for details.
Posted March 13, 2001
The latest
posts |
