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SEEING DRUGS AS A CHOICE OR AS A BRAIN ANOMALY
Dr. Alan I. Leshner, the
director of the National Institute on Drug Abuse, a division of the
National Institutes of Health, is known
for his slide shows. Two or three times a week he
gives a speech -- to treatment counselors
and prevention specialists, physicians and
policymakers -- and almost all feature
slides culled from the work of the 1,200 researchers
supported by his institute.
The slides are of brain scans, and they
usually come in pairs. The "before" slides show the
activity of a normal brain; the "after"
ones depict a brain that has had prolonged exposure to
drugs.
Lacing his presentation with jokes and
Yiddish expressions -- as a youth, Dr. Leshner
summered at a Catskills hotel owned
by his grandparents, and he has a bit of Alan King in
him -- he tries to translate the science
into plain English.
What the science shows, he says, is that
the brain of an addict is fundamentally different from
that of a nonaddict.
Initially, when a person uses hard drugs
like heroin or cocaine, the chemistry of the brain is
not much affected, and the decision
to take the drugs remains voluntary.
But at a certain point, he says, a "metaphorical
switch in the brain" gets thrown, and the
individual moves into a state of addiction
characterized by compulsive drug use. These brain
changes, Dr. Leshner says, persist
long after addicts stop using drugs, which is why, he
continues, relapse is so common.
Addiction, Dr. Leshner declares, should be approached
more like other chronic illnesses, like
diabetes and hypertension. Going further, he says that
drugs so alter the brain that addiction
can be compared to mental disorders like Alzheimer's
disease and schizophrenia. It
is, he says, a "brain disease."
In promoting this concept, Dr.
Leshner has stepped forthrightly into a debate that has
smoldered for decades: are drug addicts
responsible for their behavior?
Should they be treated as sick people
in need of help, or as bad people in need of
punishment? Dr. Leshner has come
down squarely on the side of illness.
And he is winning many people over.
Today the brain-disease model is widely accepted in
the addiction field, and Barry R.
McCaffrey, the White House drug adviser, routinely invokes
it.
Others are not convinced. "I reject
the notion that addicts fall under the spell of drugs and
become a zombie and so are not responsible
for anything they do," says Dr. Sally L. Satel, a
senior associate at the Ethics and Public
Policy Center in Washington and a practicing
psychiatrist at a methadone clinic.
To her and other critics, the brain-disease
model is a new orthodoxy based less on science
than on a desire to soften the stigma
attached to addiction.
The idea that addiction is a disease
is not new. In the 1960's Alcoholics Anonymous began
speaking of alcoholism as a disease.
But, initially at least, A.A. used
the term figuratively to suggest the tenacious hold drinking
has on alcoholics. Over the last
decade or so, however, advances in brain-imaging technology
have allowed researchers to measure
the impact of psychoactive substances on the brain with
increasing precision. Investigators
have found that drugs like cocaine, heroin and alcohol
increase the brain's production of dopamine,
the neurotransmitter that regulates pleasure,
among other things.
This helps account for the euphoric high
drug users feel. But these drugs deplete the
dopamine pathway, disrupting the individual's
ability to function.
At the Brookhaven National Laboratory
on Long Island, for instance, Dr. Nora D. Volkow
has found that even 100 days after a
cocaine addict's last dose, there is significant disruption
in the brain's frontal cortical area,
which governs such attributes as impulse, motivation and
drive.
Dr. Volkow says that "the disruption
of the dopamine pathways leads to a decrease in the
reinforcing value of normal things,
and this pushes the individual to take drugs to
compensate." Other researchers have
found a physiological basis for the craving so many
addicts experience, but it is not yet
clear how long such physiological changes remain.
Dr. Herbert D. Kleber, the
medical director of the National Center on Addiction and
Substance Abuse in New York, says that
the brain-disease concept fits with his experience
with thousands of addicts over the years.
"No one wants to be an addict," he says. "All
anyone wants to be able to do is knock
back a few drinks with the guys on Friday or have a
cigarette with coffee or take a toke
on a crack pipe. But very few addicts can do this. When
someone goes from being able to control
their habit to mugging their grandmother to get
money for their next fix, that convinces
me that something has changed in their brain."
But does causing changes in the brain
qualify addiction as a brain disease? Not according to
Dr. Gene M. Heyman, a lecturer
at the Harvard Medical School and a research psychologist
at McLean Hospital in Boston.
"Since we can visualize the brain of someone who's craving,
people say, 'Ah hah, addiction is a
brain disease,' " he remarks. "But when someone sees a
McDonald's hamburger, things are going
on in the brain, too, but that doesn't tell you whether
their behavior is involuntary or not."
While acknowledging that addiction does induce
compulsive behavior, Dr. Heyman
says that addicts still retain a degree of volition, as
evidenced by the many who stop using
drugs.
"Smoking meets the criteria for addiction,
but 50 percent of smokers have quit," he says.
This change, he goes on, is "demonstrably
related" to the data about the hazards of smoking
that have emerged since the surgeon
general's report on the subject in 1964. By contrast, Dr.
Heyman says, "information about schizophrenia
hasn't reduced the frequency of that illness."
Dr. Heyman also cites a well-known
study of Vietnam veterans who were dependent on
heroin while overseas.
Within three years of their return to
the United States, the study found, nearly 90 percent
were no longer using it -- strong evidence,
Dr. Heyman says, that the addictive state is not
permanent.
Sally Satel first became skeptical about
the brain-disease model in 1997, when she attended a
conference of the drug-abuse institute
on the medical treatment of heroin addiction. "So
pervasive was the idea that a dysfunctional
brain is the root of addiction that I was able to sit
through the entire two-and-a-half-day
meeting without once hearing such words as
'responsibility,' 'choice,' 'character'
-- the vocabulary of personhood," Dr. Satel wrote in a
paper called "Is Drug Addiction a Brain
Disease?"
Written with Dr. Frederick K.
Goodwin and published as a booklet by the Ethics and Public
Policy Center, the paper offers a blistering
attack on the drug-abuse institute and its
brain-disease terminology. "Dramatic
visuals are seductive and lend scientific credibility to
NIDA's position," the paper states,
but politicians "should resist this medicalized portrait for at
least two reasons.
First, it appears to reduce a complex
human activity to a slice of damaged brain tissue.
Second, and most important, it vastly
underplays the reality that much of addictive behavior is
voluntary."
To support that claim, Dr. Satel
cited the results of the Epidemiologic Catchment Area study,
paid for by the National Institute of
Mental Health, which asked 20,300 adults about their
psychological history.
Of the 1,300 people who were found to
have been dependent on or abusing drugs, 59 percent
said they had not been users for at
least a year before the interview; the average time of
remission was 2.7 years. "The
fact that many, perhaps most addicts are in control of their
actions and appetites for circumscribed
periods of time shows that they are not perpetually
helpless victims of a chronic disease,"
Dr. Satel said.
At the mention of Dr. Satel, Dr.
Leshner bristles. "Simplistic and polarizing," he says of her
writing.
More generally, Dr. Leshner maintains
that his views have been distorted and
misinterpreted. Still, he says,
he has lately modified his message, giving more recognition to
the role of volition in addiction.
"Today's version," he says, is that addiction is "a brain
disease expressed as compulsive behavior;
both its development and the recovery from it
depend on the individual's behavior."
But where does choice end and compulsion
begin?
The slide showing that has not yet appeared. |