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 non-addict. 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.
Michael Walker specializes in treating addiction and chemical dependency.
